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My Plan to Achieve Energy Freedom - The Road to Zero Energy Bills

  • 17-01-2016 9:34pm
    #1
    Registered Users Posts: 263 ✭✭ Conor20


    I've long been interested in energy efficiency and renewable energy projects. I now finally have a canvas to try these out on - We bought a house about a year ago, and it's a typical early-boom-time late 80's/early 90's build. It's paper thin. There was no insulation in the house at all. The windows were single glazed. The front door.. Well let's just say, the rain came in, in large puddles, under the door during the winter storms the first year we were in there. Coupled with this, I've been hunting for ways to cut down on expenditure and find ways of generating decent returns for the (far away) retirement fund without a huge amount to save each month. The electricity and heating bills for the first year we spent in the house were really expensive, as was the cost of running the car, and I had this terrible vision of us running on the treadmill forever, just working to keep ahead of these expenses.

    Around the same time, I was really impressed with some projects posted on Boards - particularly the DIY Rainwater Harvester built by a poster on the Plumbing and Heating board, as well as the posts from several people who have installed solar panels - both hot water and electricity generation. I've also learned a lot about financial efficiency, and calculating Return on Investments from the American blogger, Mr Money Mustache (though I'm more interested in energy than money). I decided to be more proactive in shedding these electricity, heating and transport expenses, so we could spend that money on other things that bring at least some benefit to us, or to use it to start saving for retirement. I decided to do some small steps - buying an energy monitor for the house and starting with switching all of the lights in the house from incandescent to LEDs. This was a bit of a revelation for me. It cost €55 to buy the LEDs online. They are rated to last about 15 years, and they saved €87 in the first year. That means they paid for themselves in less than a year, and they're going to save €87 * 14 = €1,218 over their 15 year lifetime. If I put that money in the bank, it'd be worth perhaps about €150 in 15 years. In the stock market, it might be worth between €0 and €500. It's certainly unlikely to be worth €1,200. And so I came to the realisation that with technology that has come along in the last few years, it seems conceivable that it may be possible to completely remove the €4000 or so of energy bills between electricity, heating and petrol we're paying each year. If I retire in 35 years, that's €4000 * 35 = €140,000 that we could spend on other things (or not have to earn, and pay tax on, in the first place).

    And so I started planning, and costing energy initiatives to calculate their payback, and whether they save more money than they cost in the long run. If they do, and the return is better than what I might expect to get from a bank or the stock market, then it makes more sense to do it than do anything else. I was surprised by the quick paybacks, and how much sense it makes to do a lot of these things - installing LEDs, putting in insulation, installing double glazed windows, installing a wood burning stove with a back boiler to heat the house, switching to an electric car. This is my plan:
    1. Put in an energy monitor so we can see what's consuming and costing us what, and how much we're saving with these updates.
    2. Change all light bulbs to LEDs
    3. Put in radiator heat reflectors to stop sending half of our heating out of the house
    4. Insulate the attic
    5. Install a wood burning stove with back boiler to reduce gas heating costs
    6. Replace the petrol car with an Electric Car
    7. Retrofit Dual flush, low water toilet cisterns
    8. Install Double Glazed Windows
    9. Install a Rain water recycling system to fill the toilet cisterns with rain water
    10. Install Solar PV Panels to reduce electricity bills
    11. Add a battery system for Solar PV Panels to completely remove energy bills forever
    12. Put in an Air Source heat pump and remove the gas boiler forever
    13. Install an inverter to allow the house to be powered by the electric car
    14. If necessary, add Solar panels for hot water
    15. Selling energy to the grid. The final frontier - actually making money from energy and beyond. (Hopefully this becomes possible in Ireland at some point in the future)
    16. End Game: Retire on energy income, invested energy cost savings and super-low living costs.

    The last one might be a stretch, but I like having it to aim for. I decided to keep a blog on the way there because it worked out well when I wanted to do an Ironman a few years ago. I'll keep a blog of my progress, and how each thing works out - in terms of cost, energy savings and financial savings. So here goes. Although it may take a few years, I'm determined to follow the plan above. I'll keep this thread updated with my progress.

    Conor.


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Comments

  • Closed Accounts Posts: 328 ✭✭ TOMP


    As far as I know owners of residential homes can not sell excess back onto the grid in this country at this time


  • Closed Accounts Posts: 3,364 ✭✭✭ rolion


    Hi Conor,

    Welcome aboard the "green virus" train !

    I read very excited your post just to realise that the dream that you have in mind (excepting the financial figures that i cannot argue with real arguments) is not possible:you're are not let go that route by the system ! The suppliers of energy,gas and oil ,then by the guvernment AND not lastly by your lifestyle !

    I have countless "white nights" of doing research just to let it go as they are not viable from any realistic, human, rational point of view!

    Basically,we humans,in the year 2016 cannot be independent energetic ! Well,without investing €30-40k in a big system and then pray that they work and don't fail.Also,doing the maths for RoI and TCO of that system...still not making the figures.

    Yes,is great that we began thinking that way but we need to asses "how much i spend" to "get back a figure" !?

    Let me share my story:
    I have 1 full month since i'm recording my electricity and gas consumption,by hand,by pen,on the back of the door's wooden table.I discovered that before doing it i was using aroound 20KWh / 20 units per day.After few days,the whole family started,without a big push,to bring that figure down.We managed to get it to 18 and now it stands at around 15 per day. So,without spending abut €150 to purchase a nice flashy touch screen device to tell me my consumption, i have saved about 5 units a day, €1 a day, €60 per bill.
    BUT...i bought a timer that powers the new "hungry" water pump in the attic. I spent €50 for it so how long until that expense is quantified or marked as covered !??

    The above analogy could be applied to all ideas...LEDs lights,i paid €20 for dimmable LEDs,6 of them,€120...how much impact had on my consumption habit or expense !? Dunno,as it creates a nice light in the room when i turn on the nearly 1.5KWh audio video system !??

    Also,please do not forget that even if your consumption is low,you still pay charges and taxes that may make all of the " savings " in the bill !
    Conor20 wrote: »

    And so I started planning, and costing energy initiatives to calculate their payback, and whether they save more money than they cost in the long run. If they do, and the return is better than what I might expect to get from a bank or the stock market, then it makes more sense to do it than do anything else. I was surprised by the quick paybacks, and how much sense it makes to do a lot of these things - installing LEDs, putting in insulation, installing double glazed windows, installing a wood burning stove with a back boiler to heat the house, switching to an electric car. This is my plan:
    1. Put in an energy monitor so we can see what's consuming and costing us what, and how much we're saving with these updates.
      I am doing this for "free",recording on the paper spreadsheet.base don day/time periods the units at the meter outside the house.True,a nice device that creates nice flashy reports for you are available.
    2. Change all light bulbs to LEDs
      Yes,been there,done that but whats the return on the spending,over how many years !?
    3. Put in radiator heat reflectors to stop sending half of our heating out of the house
      Done that,very good idea.
    4. Insulate the attic
      Actually very good idea,myself DIY insulated whole house !I will safely sayis the best ever improvement made to my home,both comfort and financially.I will really high enough advise anyone looking at the renewvle is to start with the insualtion of the house.Not only saves money but the comfort is improved massively.And dont think that you don't need it, as the quality of the work carried over by the NAMA employed developers and unskilful labour makes your house a crazy place.
    5. Install a wood burning stove with back boiler to reduce gas heating costs
      No applicable to me,cant say anything.
    6. Replace the petrol car with an Electric Car
      I will "replace" few cars and travel to Moon and back with a normal car by the time i will RoI-ed cost on an electrical car ! :)
    7. Retrofit Dual flush, low water toilet cisterns
      Done that,well worth it !
    8. Install Double Glazed Windows
      I have them,most of the homes have them fitted already.However,the quality of them,fitted by dubious greedy developers back years ago makes you think how performant are they.
    9. Install a Rain water recycling system to fill the toilet cisterns with rain water
      Too costly,you will need additional equipment,tanks,pumps,pipes.Dont forget the filters and health related aspects. RoI is way too slow and too long !
    10. Install Solar PV Panels to reduce electricity bills
      PV still needs to be pushed across the Island,as the weather conditions are not great for it.Today,a 2KW power system generated less than 80W. Im currentt working that now,but just to kill a "sick obsession" with them.Planning for a 4KW power solution,i hope to have it harvesting by the end of February.
    11. Add a battery system for Solar PV Panels to completely remove energy bills forever
      WAY WAY too expensive AND DEARER than the cost of the grid supplied KWh.
    12. Put in an Air Source heat pump and remove the gas boiler forever
      Dont have one,cant comment .
    13. Install an inverter to allow the house to be powered by the electric car
      Same,too costly i assume.
    14. If necessary, add Solar panels for hot water
      Lots of new and old homes have 20-40 tubes on the roof,more common that PVs. I have a grant paid 40 tubes,thinking in upgrading the 60 soon so that i can switch off the boiler most of he year. Waiting for the summer,to see how it performs with 40,dont need surprises when sun is bursting with excess of photons !
    15. Selling energy to the grid. The final frontier - actually making money from energy and beyond. (Hopefully this becomes possible in Ireland at some point in the future)
      Still a game of "morally viable" solution.Some people arguments are that your neighbour may pay *subsidize your roof's PV panels. If the Guvernment approves the FiT this year,it will be well worth to install a PV system,sell in summer and get paid back in winter ! But,as well,it needs to be pretty big in generated power to make it attractive. I will guess,around 5KW power on the panels. Cost,comes at anything between €7 and €10k. Then,you plan to work around it,to be more aware of it but it may end up consuming more as things is free.
    16. End Game: Retire on energy income, invested energy cost savings and super-low living costs.
      Welcome,nice dream,but please let me "wake you up" when T H I S will be recognised public of its existence ! It looks like the scientific world "sponsored" by the big energetic companies knows more about it ! :)


  • Registered Users Posts: 263 ✭✭ Conor20


    TOMP wrote: »
    As far as I know owners of residential homes can not sell excess back onto the grid in this country at this time

    Yep, this is currently the case - no utility is buying back power from people with Solar PV installed. I think this will change however, so we can bide our time - the Energy Whitepaper released by the government (and discussed in this thread) left the possibility open: "While there has been no indication as to the support rates Ireland will set, KPMG recommended an opening domestic FiT rate of €0.13/kWh, gradually decreasing to €0.02/kWh in 2030.". If this doesn't materialise, there are other options for making Solar PV economical: (1) having an EV charging during sunlight hours (2) installing a battery array when their cost comes down below the savings returned (3) creating a new collective utility to buy and sell power on behalf of Solar PV. That would be a drastic step and hopefully it wouldn't come to that, but Ireland has a deregulated electricity market in which any entity is entitled to participate once they adhere to the registration criteria and put down a bond equivalent to their maximum daily exposure on the market.
    rolion wrote: »
    Welcome aboard the "green virus" train!

    Thanks!
    rolion wrote: »
    I read very excited your post just to realise that the dream that you have in mind (excepting the financial figures that i cannot argue with real arguments) is not possible:you're are not let go that route by the system ! The suppliers of energy,gas and oil ,then by the government AND not lastly by your lifestyle ! I have countless "white nights" of doing research just to let it go as they are not viable from any realistic, human, rational point of view! Basically,we humans,in the year 2016 cannot be independent energetic ! Well,without investing €30-40k in a big system and then pray that they work and don't fail.

    I'm not sure I agree - this is just maths. If installing any system to reduce energy delivers a return greater than other available investments, then it makes sense to do that. The calculations would factor in risk (of failure, or otherwise) like any other investment. Also, larger systems would generally be under warranty. [/QUOTE]
    rolion wrote: »
    Yes, is great that we began thinking that way but we need to asses "how much i spend" to "get back a figure"!?
    This is exactly what I plan to do - (1) measure the current situation (2) understand clearly the costs and risks of any alternative investment to reduce those costs, and calculate the ROI (3) If it makes sense to proceed, do so and then measure the result against the estimate and report back.


  • Registered Users Posts: 1,097 ✭✭✭ freddyuk


    In your equation what value do you put on
    1. "grid independence" for the sake of it.
    2. Controlling your own destiny
    3. Feeling of satisfaction from self sufficiency
    4. Education of how "stuff works" ie. energy usage in and around the home.
    5. Understanding how the world produces energy and how we take it for granted.
    6. The joy of sitting watching TV while your neighbour may be in darkness huddled round a candle freezing cold.
    7. Learning how you can live within your "energy means" but if you want more over your "energy budget "you have to pay proportionately more

    I feel all these things have a value which is not a monetary amount but very relevant to having a more energy independent lifestyle and part of the decision process. It is not simply mathematics. Simply having an energy meter means your usage drops so that should be the first step.
    New technology is bringing the option within reach of everyone and that valuation is going to potentially make the difference.


  • Registered Users Posts: 1,097 ✭✭✭ freddyuk


    In your equation what value do you put on
    1. "grid independence" for the sake of it.
    2. Controlling your own destiny
    3. Feeling of satisfaction from self sufficiency
    4. Education of how "stuff works" ie. energy usage in and around the home.
    5. Understanding how the world produces energy and how we take it for granted.
    6. The joy of sitting watching TV while your neighbour may be in darkness huddled round a candle freezing cold.
    7. Learning how you can live within your "energy means" but if you want more over your "energy budget "you have to pay proportionately more

    I feel all these things have a value which is not a monetary amount but very relevant to having a more energy independent lifestyle and part of the decision process. It is not simply mathematics. Simply having an energy meter means your usage drops so that should be the first step.
    New technology is bringing the option within reach of everyone and that valuation is going to potentially make the difference.


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  • Registered Users Posts: 263 ✭✭ Conor20


    freddyuk wrote: »
    In your equation what value do you put on
    1. "grid independence" for the sake of it.
    2. Controlling your own destiny
    3. Feeling of satisfaction from self sufficiency
    4. Education of how "stuff works" ie. energy usage in and around the home.
    5. Understanding how the world produces energy and how we take it for granted.
    6. The joy of sitting watching TV while your neighbour may be in darkness huddled round a candle freezing cold.
    7. Learning how you can live within your "energy means" but if you want more over your "energy budget "you have to pay proportionately more

    I feel all these things have a value which is not a monetary amount but very relevant to having a more energy independent lifestyle...

    All of the above, except perhaps for "The joy of sitting watching TV while your neighbor may be in darkness huddled round a candle freezing cold.", are great positive side effects of trying this. I realised I didn't know much about how energy is generated, how I was using it and how I could get away from big energy bills. I have built a pretty solid understanding of these now, and it's been great so far. Researching and implementing the projects I list above will continue to build this knowledge, which has been very satisfying, as well as the money savings I mention.


  • Registered Users Posts: 263 ✭✭ Conor20


    As I mentioned, I've started the first few projects listed above, and so I thought I'd start with writing them up in case anyone else wants to try them. I found this really helpful with the rainwater harvester posted in the Plumbing Board. I want to be completely objective, so it's easy for anyone to compare each of the projects to other investments they could make (paying down their mortgage for instance - if you're paying a mortgage with an interest rate of 4%, then a wood burning stove needs to return more than 4% for it to make more sense to install than to just put that money against the mortgage). For every project, I'll calculate the € saved per year, the kWh saved per year, the payback, the return on investment, and the CO2 emissions removed. It'll be easy to compare them to each other then.

    So the first thing I did was to pick up an energy monitor. Funnily enough, this seems to be enough to reduce energy bills by a hundred or so euro a year - once people are aware of what they're consuming, they reduce it.

    EnergyMonitorDisplayUnitCloseUp.png

    This allowed me to figure out what things in the house cost to run each year:
    YearlyApplianceElectricityCostsWithoutAirConditioning.png

    I calculated this by (1) turning the thing on and watching what the energy monitor went up by and (2) plugging that figure into:
    • (Wattage × Hours Used Per Day) ÷ 1000 = Daily Kilowatt-hour (kWh) consumption
    • Daily kWh consumption × number of days used per year = annual energy consumption
    • Annual energy consumption × utility € per kWh = annual cost to run appliance

    For example:
    • Our kettle is used about 12 times per day. At 5 minutes a boil, it runs for about 1 total hour (5 minutes x 12 runs).
    • Looking at the energy monitor when it's in use, it consumes 1500W (or 1.5kW) when boiling water.
    • That's all the information we need to work out:
    • Daily Kilowatt-hour (kWh) consumption: (1,500 W × 1 hour) ÷ 1,000 = 1.5 kWh
    • The : The kettle is used almost every day of the year so that's 1.5 kWh × 365 = 547.5 kWh per year
    • The annual cost: The utility rate is €0.17 cents per kWh. 547.5 kWh × $0.17/kWh = €93.08/year

    In addition to these electricity costs, we're spending €828 a year on heating the house, and €1500 on petrol.
    So that's good - now I can figure out exactly what each of the appliances, boiler and car cost to run. Next, I want to calculate the return on investment of all of the alternatives to the costs above - for example, switching all of the light bulbs with LEDs, or installing a wood burning stove to remove gas costs.

    I started with the electric shower because it's the biggest cost. The electric shower costs €217.18 to run every year to heat the water required for 30 minutes of showers per day. The house also requires heating, currently done by heating water with the gas boiler and circulating it around the radiators. Our house has a gas boiler which cost €828.88 per year to run (that's 13,813 kWh of gas used per year emitting 3,177 kgCO2). That's €828.88 + €217.18 = €1,046.06 a year to heat water. That'd be a nice cost to get rid of.

    I am in a position where I can access wood for quite a bit cheaper than gas so I priced having a wood burning stove installed in the house with a back boiler to heat the water for the house. The stove, back boiler, new highly insulated hot water tank and plumbing came to €4000. I estimated that the running costs (e.g. the wood) would cost €155 per year. That adds up to a saving of €1,046.06 - €155 = €891.06 a year.

    The payback period of an investment is how many years it takes to pay for itself. That is the total cost / the yearly payback. In this case, that's €4000 / €891.06 = 4.5 years. So, installing the wood burning stove will pay for itself in four and a half years, then save €891.06 * 5 = €4,455.3 over the following five years, and every five years after that.
    Payback:
    • Cost: €4000
    • Saving: €891.06 per year
    • Payback period: €4000 / €891.06 = the stove pays for itself in 4.5 years
    • Saving over 20 years: €891.06 * 14.5 = €12,920.37
    • Yearly Return: 20.72%

    I didn't expect a return of 20.72%.. Our mortgage rate is 4% so we would save a lot more money by installing the wood burning stove than paying down the mortgage with €4k in we had it. In fact, a hedge fund manager would probably be a superstar if he could deliver a return of 20% on your money for even two years in a row. But.. one problem - I didn't have €4k to spare! So I had to start a bit smaller than that and use those to pay for the bigger investments over time. But at least I now had my method of calculating return on investments to see if it made sense to do them, or to pay down the mortgage, or try save it in the bank or wherever.

    So I did some more calculations and started by replacing every light bulb in the house with LEDs.

    All light bulbs convert electricity to light. The way that this conversion is done however, has a massive impact on how much electricity they consume, and how much they cost you. Here's an all up energy consumption comparison between the three main types of bulb: incandescent (bad), CFL (a stop gap until LEDs came along) and LED (good).
    Step2_LEDEnergyConsumotion.jpg
    Thomas Edison invented the incandescent light bulb nearly 120 years ago, and it still works pretty much as it did then. Inside a glass bulb, electricity heats up a wire filament, causing it to glow and give off light. The problem is that more than 90% of the energy produced by incandescent lights is heat, not light. That's 900% more electricity being consumed than necessary, that you're paying for. In fact, Incandescent light bulbs are now deemed to be so wasteful, that their sale is now illegal (
    2012<http://www.irishexaminer.com/ireland/lights-out-for-old-style-edison-bulb-on-saturday-205700.html> ) in Ireland and across the EU as of September 2012.

    As an added bonus, because LEDs don't generate any heat, they last way, way longer than Incandescents:
    Step2_LEDLifeTime.jpg.png

    Calculating the Energy Saving:
    Watching my energy monitor, I started replacing incandescent GU10 light bulbs in a light rig in my kitchen one by one to measure the reduction in consumption. Each incandescent consumed just under 41 watts. Each LED consumes 4.5 watts. There are four bulbs in the rig, so after fitting the LEDs: 163 watts reduced to 18 watts. That's a 145 watt reduction. These lights are on for about 1.5 hours per day --> 145 watts * 2 light rigs * 1.5 hours a day = 435 Watt hours per day. 435 *365 days a year = 158,775 /1000 = 158.775 kWk per year. To quickly work out the emissions savings: Ireland's CO2 intensity is 535g CO2 per kWh. .535 * 159 = 85.065 kg CO2. Changing 8 light bulbs in my kitchen will avert 85kg of CO2 a year.

    Calculating the Payback:
    So all in, that’s a saving of 159 kWh per year. At the electricity price of €.17 / kWh, that means a financial saving of€27.01 per year. The 8 LEDs cost €22, so the payback is €22 / €27.01 = 0.81 years. So they pay for themselves in under a year. I repeated this for the whole house, and the savings come to 495.165 kWh per year | €87.29 per year | 274.8697 Kg CO2 per year. Time to complete the change: 2 hours to shop for the LED bulbs on DX.com and 2 hours to replace all the bulbs in the house while watching the energy consumption drop on the energy monitor. The LED bulbs came to €68 in total.

    I found these pretty useful in deciding what LEDs to buy for each room. I was initially unsure as to whether LEDs would be too harsh for the bedrooms, but it turns out you can get LEDs in any color you want. You can simply decide on the temperature of the colour of light you want, and buy that bulb:
    Step2_WhatLEDsShouldIBuy.jpg

    Here's the full range:
    Step2_WhatLEDsShouldIBuyFullColourRange.jpg

    So all in all, replacing all lights in the house with LEDs:
    Cost: €68
    Saving: €87.29 per year (495.1 kWh per year | €87.29 per year | 274.8 kg CO2 per year)
    Payback period: €68 / €87.29 = 0.78 = the LEDs pays for themselves in about 10 months
    Saving over the 15 years estimated lifetime: €87.29 * 15 = €1,309.35 - €68 = €1,241.35
    Yearly Return on Investment: 114.9%
    Full Return on Investment: 1725%

    That was a good start!


  • Registered Users Posts: 1,097 ✭✭✭ freddyuk


    Just taking a quick point as that is a lot to go through.
    Did you calibrate the energy meter? Switch a known load to check it is accurate (at least 1kw). These thing are very inaccurate below 200watts so you need to have a control baseline you can trust and then switch on your small loads on top of this to measure more accurately. Your electricity meter is going to be dead accurate so you can check this for 24 hours and cross reference with the monitor.
    Also 5 minutes for a kettle is surely a full kettle? Just put in what you need. Massive saving.


  • Registered Users Posts: 1,097 ✭✭✭ freddyuk


    Just taking a quick point as that is a lot to go through.
    Did you calibrate the energy meter? Switch a known load to check it is accurate (at least 1kw). These thing are very inaccurate below 200watts so you need to have a control baseline you can trust and then switch on your small loads on top of this to measure more accurately. Your electricity meter is going to be dead accurate so you can check this for 24 hours and cross reference with the monitor.
    Also 5 minutes for a kettle is surely a full kettle? Just put in what you need. Massive saving.


  • Closed Accounts Posts: 3,364 ✭✭✭ rolion


    Great sharing, thanks.

    Above all the mentioned already, i have done few things:

    -setup the attic' water pump on timer;
    -setup the under floor heating pump and valve on timer;
    -heating and radiators setup at 19 degrees downstairs and 20 degrees in bedrooms

    I'm reading manually the meters for electricity and for gas and keep them on the back of the door.
    Saved around 5 E-units daily and only few G-units since starting and implementing measures.

    I'm discussing with my family one more thing:
    -a blue day when we do not use gas to heat at all, by switching the boiler off from 9am to 11pm
    -a green day with minimum electricity appliances used if possible
    Most of the above is already Monday to Friday so looking at weekend if doable

    Keep in touch.


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  • Closed Accounts Posts: 3,364 ✭✭✭ rolion


    Great sharing, thanks.

    Above all the mentioned already, i have done few things:

    -setup the attic' water pump on timer;
    -setup the under floor heating pump and valve on timer;
    -heating and radiators setup at 19 degrees downstairs and 20 degrees in bedrooms

    I'm reading manually the meters for electricity and for gas and keep them on the back of the door.
    Saved around 5 E-units daily and only few G-units since starting and implementing measures.

    I'm discussing with my family one more thing:
    -a blue day when we do not use gas to heat at all, by switching the boiler off from 9am to 11pm
    -a green day with minimum electricity appliances used if possible
    Most of the above is already Monday to Friday so looking at weekend if doable

    Keep in touch.


  • Registered Users Posts: 2,820 ✭✭✭ air


    If you live in an urban area it would be better for your local environment to stick with your gas heating instead of installing a wood burner.
    Also even if you get chopped, seasoned wood delivered to your shed for €150, you'll still have to load it into the house, manage the fire all day and dispose of ashes every day. The 2 or 3 euro a day you stand to save will be well earned.
    When you get the €4k together it would be far better spent on improving your air tightness and insulation.


  • Registered Users Posts: 2,820 ✭✭✭ air


    If you live in an urban area it would be better for your local environment to stick with your gas heating instead of installing a wood burner.
    Also even if you get chopped, seasoned wood delivered to your shed for €150, you'll still have to load it into the house, manage the fire all day and dispose of ashes every day. The 2 or 3 euro a day you stand to save will be well earned.
    When you get the €4k together it would be far better spent on improving your air tightness and insulation.


  • Registered Users Posts: 74 ✭✭ B9K9


    Conor20 wrote: »
    All of the above, except perhaps for "The joy of sitting watching TV while your neighbor may be in darkness huddled round a candle freezing cold.", are great positive side effects of trying this. I realised I didn't know much about how energy is generated, how I was using it and how I could get away from big energy bills. I have built a pretty solid understanding of these now, and it's been great so far. Researching and implementing the projects I list above will continue to build this knowledge, which has been very satisfying, as well as the money savings I mention.

    Shirley FreddyUK meant schadenfreude? ;)


  • Posts: 0 [Deleted User]


    freddyuk wrote: »
    In your equation what value do you put on
    1. "grid independence" for the sake of it.

    Warm Fuzzy. 4X Grid charges diminishing.
    freddyuk wrote: »
    2. Controlling your own destiny

    Mandatory
    freddyuk wrote: »
    3. Feeling of satisfaction from self sufficiency

    Hard to find time in the day to check all the meters.
    freddyuk wrote: »
    4. Education of how "stuff works" ie. energy usage in and around the home.

    Less is more. Turning loads off and energy efficient devices are 2/3 the generator.
    freddyuk wrote: »
    5. Understanding how the world produces energy and how we take it for granted.

    Converts energy. :P
    freddyuk wrote: »
    6. The joy of sitting watching TV while your neighbour may be in darkness huddled round a candle freezing cold.

    Mwahaha, no standing charges, no bills, more reliable system. Priceless.
    freddyuk wrote: »
    7. Learning how you can live within your "energy means" but if you want more over your "energy budget "you have to pay proportionately more

    Or connect alternative alternative generators.
    rolion wrote: »

    Add a battery system...
    WAY WAY too expensive AND DEARER than the cost of the grid supplied KWh.

    It can be done for slightly more than parity. Shop around, go easy on the kool-aid.

    Conor20 wrote: »
    In fact, Incandescent light bulbs are now deemed to be so wasteful, that their sale is now illegal (
    2012<http://www.irishexaminer.com/ireland...ay-205700.html> ) in Ireland and across the EU as of September 2012.

    Only their manufacture. Not their sale. But the bubble within a bubble is an interesting loop-hole. You can make all the 2kW incandescents you want. pacman.gif
    Conor20 wrote: »
    As an added bonus, because LEDs don't generate any heat

    Oh yes they do. All electronics produce heat directly proportional to their efficiency.
    Conor20 wrote: »
    but it turns out you can get LEDs in any color you want.

    But not full spectrum.
    Incandescent are still the best at colour rendering. Inefficient light bulbs but great light + heat sources. redface.png
    Conor20 wrote: »
    That's 900% more electricity being consumed than necessary

    Not quite.


  • Registered Users Posts: 263 ✭✭ Conor20


    freddyuk wrote: »
    Just taking a quick point as that is a lot to go through.
    Did you calibrate the energy meter? Switch a known load to check it is accurate (at least 1kw). These thing are very inaccurate below 200watts so you need to have a control baseline you can trust and then switch on your small loads on top of this to measure more accurately. Your electricity meter is going to be dead accurate so you can check this for 24 hours and cross reference with the monitor.

    Yep, I have two meters to double check the measurements of individual appliances: one which clips onto the wire into the house beside the electricity meter, and one which is a plug meter like this one:
    1024px-Plug-in_Power_%26_Energy_Monitor_in_UK_Domestic_Mains_Socket.jpeg


  • Registered Users Posts: 263 ✭✭ Conor20


    I've undertaken step two now, which was a pretty simple one: I put in radiator heat reflectors to stop sending half of our heating out of the house. Lidl were selling the heat reflector foil pretty cheaply, so I thought it was worth a try, though I see you can also buy it online.

    It's a pretty simple one: Radiators which are mounted on external walls will radiate some of their heat into those walls and out into the air, at no benefit to you. A simple measure to maximise the use of the heat generated in your house is to put heat reflecting foil behind those radiators to reflect that heat back into the house. This is the idea:
    HeatReflectorBehindRadiator.jpg

    This is an infrared image showing a house with two radiators, one with a reflector and one without. You can see the increase in heat escaping uselessly outside on the side without the reflector:
    HeatReflectorIRImage.png

    And this is the basic idea:
    TheIdea.png

    Here’s a video on actually fitting the foil. It's about a 30 minute job.

    Heat energy seems different from electrical energy, but it's actually not. We can measure both in kWh. We may get separate bills for electricity and gas (or oil, or whatever) but once we know how much they cost per kWh, the cost, kWh saving and payback of each energy saving step can be worked out for any measure and directly compared.

    The Saving and Payback - kWh, $, and kgCO2
    The energy saving of foil reflectors depends on a lot of things, so we'll need to generalise here a bit. The foil is reflecting heat which would otherwise have been absorbed and conducted out of the house by the wall behind the radiator. Some energy travels out of the radiator in the form of convection, not radiation, which won't be effected by this process. Long story short - if your walls feel cold when your house is relatively warm, it means they are not well insulated and will benefit from radiator reflectors. To try to quantify the savings in my house, I see Radflek is a reflector approved by the UK Carbon Trust. The reflector saves up to 83 kWh of energy per year. This is probably an upperbound, so I'm going to go with 40kWh per year. Gas currently costs €0.08 per kWh, so the yearly saving is €0.08 * 40 = €3.20 per radiator per year.

    There are 7 radiators in our house, so that's 40 * 7 = 280 kWh saved per year. That's 280 * €0.08 = €22.40 saved per year. Hence, the heat reflector roll pays for itself in 15 / 22.40 = 0.6696 years, or about 7 months. The 10 year saving is €22.40 * 10 year = €224 - the initial €15 purchase cost = €209.

    In terms of emissions, Gas emits .23kg CO2 per kWh from a gas boiler with reasonable efficiency, so the yearly saving is 280 kWh of gas saved * .23kg CO2 per kWh = 64.4 kg CO2 averted per year, or 64.4 * 25 = 1,610.0kg CO2 over 25 years.

    Summary:
    • Cost: €15
    • Payback: 7 months
    • Saving per year: €22.40 per year | 280 kWh | 64.4 kg CO2
    • 25 year Saving: €545 | 7,000 kWh |1,610 kg CO2

    €500 and 1.5 tonnes of CO2 saved with a few strips of aluminium foil - not bad!


  • Registered Users Posts: 1,678 ✭✭✭ MAJJ


    Conor20 wrote: »
    I've undertaken step two now, which was a pretty simple one: I put in radiator heat reflectors to stop sending half of our heating out of the house. Lidl were selling the heat reflector foil pretty cheaply, so I thought it was worth a try, though I see you can also buy it online.

    It's a pretty simple one: Radiators which are mounted on external walls will radiate some of their heat into those walls and out into the air, at no benefit to you. A simple measure to maximise the use of the heat generated in your house is to put heat reflecting foil behind those radiators to reflect that heat back into the house. This is the idea:
    HeatReflectorBehindRadiator.jpg

    This is an infrared image showing a house with two radiators, one with a reflector and one without. You can see the increase in heat escaping uselessly outside on the side without the reflector:
    HeatReflectorIRImage.png

    And this is the basic idea:
    TheIdea.png

    Here’s a video on actually fitting the foil. It's about a 30 minute job.

    Heat energy seems different from electrical energy, but it's actually not. We can measure both in kWh. We may get separate bills for electricity and gas (or oil, or whatever) but once we know how much they cost per kWh, the cost, kWh saving and payback of each energy saving step can be worked out for any measure and directly compared.

    The Saving and Payback - kWh, $, and kgCO2
    The energy saving of foil reflectors depends on a lot of things, so we'll need to generalise here a bit. The foil is reflecting heat which would otherwise have been absorbed and conducted out of the house by the wall behind the radiator. Some energy travels out of the radiator in the form of convection, not radiation, which won't be effected by this process. Long story short - if your walls feel cold when your house is relatively warm, it means they are not well insulated and will benefit from radiator reflectors. To try to quantify the savings in my house, I see Radflek is a reflector approved by the UK Carbon Trust. The reflector saves up to 83 kWh of energy per year. This is probably an upperbound, so I'm going to go with 40kWh per year. Gas currently costs €0.08 per kWh, so the yearly saving is €0.08 * 40 = €3.20 per radiator per year.

    There are 7 radiators in our house, so that's 40 * 7 = 280 kWh saved per year. That's 280 * €0.08 = €22.40 saved per year. Hence, the heat reflector roll pays for itself in 15 / 22.40 = 0.6696 years, or about 7 months. The 10 year saving is €22.40 * 10 year = €224 - the initial €15 purchase cost = €209.

    In terms of emissions, Gas emits .23kg CO2 per kWh from a gas boiler with reasonable efficiency, so the yearly saving is 280 kWh of gas saved * .23kg CO2 per kWh = 64.4 kg CO2 averted per year, or 64.4 * 25 = 1,610.0kg CO2 over 25 years.

    Summary:
    • Cost: €15
    • Payback: 7 months
    • Saving per year: €22.40 per year | 280 kWh | 64.4 kg CO2
    • 25 year Saving: €545 | 7,000 kWh |1,610 kg CO2

    €500 and 1.5 tonnes of CO2 saved with a few strips of aluminium foil - not bad!

    Am enjoying this thread Conor, will shortly be refitted my new home, built 1960s, so new glazing, electric, lighting and plumbing


  • Posts: 0 [Deleted User]


    Just a thought....wouldn't the radiators serve better on internal walls than under windows, behind curtains on external walls? Isn't heating a concrete mass more efficient than air heating?


  • Registered Users Posts: 2,820 ✭✭✭ air


    The reason radiators are located under windows is to prevent drafts. The surface of the window cools air which then drops down and is reheated by the radiator. If the radiator is on the far side of the room, the cold air has to fall down and travel across the room to the radiator again. This makes the occupants of the room feel far colder.


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  • Registered Users Posts: 263 ✭✭ Conor20


    Step three! Tap Aerators.

    This was a simple, low cost, but effective project. It was a fun science project for my son also - measuring how much water was flowing before and after the aerators, and otherwise splashing water around in the name of science. A tap aerator (or faucet aerator) can be screwed onto the faucet head, creating a no-splashing stream and often delivering a mixture of water and air. This is quite useful for reducing the amount of water coming out of the faucet without reducing it's usefulness. In fact - it actually creates a stream of water which doesn't splash when it hits objects (such as your hands or implements you're washing in the sink). The water doesn't splash as readily because the air bubbles in the aerated water collapse on contact, which absorbs energy which would otherwise have sent water splashing out of the sink.

    TapAeratorInstallation.png

    The Payback analysis:
    • Cost of the Aerator set: €4
    • Savings: €63.73 per year | 38 kWh per year| 21 kgCO2 per year
    • Payback Period: 0.0628 years. This pays for itself in 23 days!
    • 10 year payback: €633.3
    • 10 Year Return on Investment: A rather startling 15,725% (Total cost = €4, Total savings = €633.3)
    • Annualised Return on Investment: 1571.2%

    Buying and Installing Faucet Aertors
    I bought this Aerator set in Lidl for €4, they are also easy to find cheaply on the internet (here or here).

    I also see an interesting Kid’s Water Saving Kit on Amazon with a tap aerator, shower aerator, toilet cistern flush volume reducer and a few other things. That could be pretty good for a fun, educational project with a child. The kit above included a plastic wrench for unscrewing the existing, but actually, a variable sized wrench was more effective, so it’s probably easier and cheaper just to buy the aerator itself.

    Fitting the aerators are very simple. You unscrew the existing fixing:
    TapAeratorInstallation1.png

    The old one looked like this:
    TapAeratorInstallation2.png

    The new one looked like this:
    TapAeratorInstallation3.png

    Then screw on the new aerator:
    TapAeratorInstallation4.png

    The flow of the water went from this:
    TapAeratorInstallation5.png

    To this:
    TapAeratorInstallation6.png

    Measuring the saving and payback
    To measure the payback, I needed to figure out (1) How much less water the aerated tap uses per minute and (2) how many minutes per day/year the taps are used. To do this, I timed how long it took to fill a 1 litre container with the old and new aerators:
    • Pre tap aerator: 1 Litre in 5.8244 seconds
    • With tap Aerator: 1 Litre in 10.1067 seconds

    The times when we’re actually filling something with a specified volume of water (like putting water in the kettle) will obviously be unaffected, because we’re going to keep filling until that thing is full, so it’s just when we’re using the tap for things like hand washing, washing up, etc. that the aerator will save water. I would guess that we use the tap in this “free flow mode” for about 5 minutes per day. So the water consumption with the old and new fittings are:

    There are 5 * 60 = 300 seconds in 5 minutes, so:
    • Pre tap aerator: 1 Litre in 5.8244 seconds means 300 / 5.8244 = 51.5075 litres per day, or 51.5075 * 365 = 18,800.2375 litres per year
    • With tap Aerator: 1 Litre in 10.1067 seconds 300 / 10.1067 = 29.6833 litres per day, or 29.6833 * 365 = 10,834.4045

    So the yearly saving comes to 18,800 – 10,834 = 7,966 litres of water per year in the kitchen sink. The two bathroom sinks are used about half as much, so if they’re used for 2.5 minutes each day, that means 5 minutes in total between them, so the number will be the same as the kitchen: 7,966 litres of water saved per year. Giving a total saving for the house of 15,932 litres.
    • Financial Payback: Water is charged for at €0.004 per litre (€3.70 per 1000 litres) in Ireland after the initial allocation is used up. That means saving 15,932 litres of water a year gives a yearly saving of 15,932 * €0.004 = €63.73
    • Energy Saved (kwh): We pay for the energy consumed treating and pumping the water to our house in the cost of the water, so this won’t be a direct saving to us. Nevertheless, I was curious to know the energy saving. From here, To supply and treat 1m3 of tap water takes around 1.2kWh of electrical energy. There is 1000 litres in 1m^3 of water, so 1 litre emits 1.2 / 1000 = 0.0012kWh. So yearly, saving 15,932 litres, saves 15,932 * 0.0012 = 19.1184 kWh. After use, the water goes into the sewage system and needs to be treated also, which results in a comparable energy consumption, so that brings the total to 19.1184 * 2 = 38kWh per year.
    • Emissions: The grid intensity of Ireland is about 450 gCO2 per kWh. That means saving 15,932 litres of water, which saves 19.1184 kWh per year averts 19.1184 * .450 = 8.6033 kgCO2. After use, the water goes into the sewage system and needs to be treated, which results in 0.781g CO2 per litre (it’s more than just the emissions from the energy generation because waste water treatment also releases methane). So 15,932 litres * 0.781g CO2 per litre = 12,442.892 gramms per year or 12.4 kgCO2. Giving a grand total of 8.6 + 12.4 = 21.0462 kgCO2 per year.

    So, The Payback analysis:
    • Cost of the Aerator set: €4
    • Savings: €63.73 per year | 38 kWh per year| 21 kgCO2 per year
    • Payback Period: 0.0628 years. This pays for itself in 23 days!
    • 10 year payback: €633.3
    • 10 Year Return on Investment: 15,725% (Total cost = €4, Total savings = €633.3)
    • Annualised Return on Investment: 1571.2%

    The Conclusion
    With a ROI of 15,725%, this may well be the best €4 I have ever invested! It makes sense for anyone with €4 to their name to do this immediately. It’s very simple to do – anyone can install tap aerators. If you're outside of Ireland also - Ireland has one of the cheapest water charges per litre in the developed world, so for most other countries, the savings will be higher than I have calculated above.


  • Registered Users Posts: 263 ✭✭ Conor20


    When we moved into our house, it had single glazed windows, no attic insulation, and a host of leaks. The wind basically blew straight through it, and it took the heat with it. After installing attic insulation, and adding new rubber seals around the windows and some doors, we decided one of the next moves we would undertake was to install double/triple glazed windows.

    The double glazed windows ready to be installed:
    DoubleGlazedWindowsReadyToInstall.jpg

    I’ve been approaching these energy improvements formulaically since the start: How much does it cost to implement? How much will it save each year? How long will it take to pay for itself, and is there any other thing I could do before it with a better payback period? This one however, I think, may be a special case. When I do the maths around Double Glazed Windows, the payback is actually a lot longer than you might expect given it tends to be the Go-To energy saving measure that most people think of when they think about upgrading the energy performance of their house. We are looking at savings of €303 in gas costs per year (I can’t get that exact figure because I’ve installed a wood burning stove with a back boiler, which is also eating into the gas costs). At €7,000 for the installation of the windows, that means a payback period of €7000 / €303.21 = 23.09 year payback. Yikes! Switching to LED lights paid for itself in 9 months, and switching to the Electric Car pays for itself in 5.4 years. 23 years seems like a very long time indeed. So why am I considering it?

    Well – I think it’s because all energy is not perceived equally. There’s a quality of life issue here as well. Loosing 10kWh per day on an inefficient dishwasher is a terrible waste, but it doesn’t make you cold when you’re eating your dinner. Poorly performing windows do. They also add to the security of the house (our previous windows would have taken approximately one point two seconds to break into), the reduced noise from the road and reduced maintenance on the new, higher quality handles and openings. These are not directly quantifiable into kWh (and hence cost and emissions) savings – but they heavily influenced our decision to proceed with the windows ahead of say, installing Solar PV panels, which would pay for themselves in about 11 years.

    The Payback Analysis
    Before the windows were installed, for the first five months of 2015, we used 7,896kWh of gas (in that same period, we used 15,792kWh of wood). I’m going to estimate a 20% saving in heat required by the house – we have some large bodies of glass, particularly in the living areas, and this seems to be the average quoted online. 7,896kWh for 5 months translated to 18,950.4 kWh of gas used per year before the double glazed windows are installed. If the windows save 20% of this, that means they save 3,790.08 kWh (18,950.4kWh * .2 = 3,790.08 kWh ). Gas costs €0.08 per kWh, which means 3,790.08kWh * .08 = €303.21 saved. €7000 / €303.21 = 23.09 year payback.

    In terms of emissions savings, 3,790.08 kWh / 11.4772 kWh per M^3 = 330.2269 M^3 per year, and gas emits 2.13793103448275 kg of CO2 per M^3, so the emissions savings are 330.2 * 2.14 = 706 kg CO2 per year. That will amount to 21,180 kgCO2 over the 30 year lifetime of the windows. Twenty one thousand kg of CO2 prevented with one measure is a pretty good haul.

    The Numbers
    • Cost of Installing Double Glazed Windows: €7,000
    • Yearly Heating Savings from the Windows: €303.21
    • Savings: €303.21 per year | 3,790.08 kWh per year | 706 kgCO2 per year
    • Payback Period: 23 years
    • 30 year payback: €2096.3 (30 years * €303.21 saving per year = €9,096.3 – €7000 original installation cost = €2096.30)
    • 30 Year Return on Investment: 29.9%
    • Annualised Return on Investment: 1%

    The Installation
    The installation of double/triple glazed windows is not overly long or difficult. It took three days in our house. The windows are measured in advance and manufactured to fit the exact measurements so when the windows arrive, the process is as such: (1) remove the old windows and frames, (2) slide in the new window frames (3) spray expanding insulating foam around the frames so they are fully sealed (4) re-finish any areas on the window boards or walls around the windows which were damaged so everything looks as good as new.

    It took three days for this process in our house, and have been fully fit into the house for eight months.

    The new (Black) and old (brown) front door. The difference in terms of weatherproofing is phenomenal. The wind used to literally blow through the old front door. The new one is fully sealed, both to the cold, and to noise from the outside. Also, it looks much better:
    DoubleGlazedWindows_NewAndOldFrontDoor.jpg

    I wanted to experience a winter with the new windows before writing this post, so I could fully understand the difference they make in cold temperatures. The difference has been huge – like the wood burning stove, they have contributed hugely to the feeling of cosiness in the house. The hall is no longer a place you have to run through on cold evenings – the new front door is fully sealed against the searing South Westerly winds hammering against it during the yearly winter storms. The downstairs rooms are also noticeably warmer.

    Finally, because heat lasts longer in the house, they have increased our ability to heat the house solely with wood. Once it’s above about 4C outside overnight, we can light the fire in the wood burning stove in the evening, and that will contribute enough heat to keep the house warm overnight without the need to add additional heating with the gas boiler. Previously, we needed to turn on the gas late at night every night in Autumn and Spring. That gets us a lot further along the route to energy independence, and saves us a decent bit of money. The verdict: The financial payback is quite long, but the intangibles (comfort, security, noise reduction) are very valuable. If you currently have singled glazed windows, installing double or triple glazed windows is definitely worth doing.


  • Registered Users Posts: 263 ✭✭ Conor20


    When looking at energy consumption to find the next best area of attack, people often seem to overlook transport, so the next thing I want to do is to understand what the energy consumption and cost is across the different transport options I chose are. I had assumed that becoming more efficient with the amount of money I spend on energy should start in the house.. But then I did a very simple comparison:
    TransportCostsandEnergyConsumption.png

    In terms of straight up kWh consumption, a car consumes WAY more than what it takes to power the contents of a house:
    kWhConsumptionOfAHouseVersusCar.png

    Holy smokes.. This is certainly an area where I was wasting a serious amount of money. Pretty polluting too. There has to be a better way!

    How could I go about reducing this cost?
    The first and most obvious way of removing this €2,277 petrol spend is to find a way not to drive. If I buy a bike for €600 and use it for 5 years, that's a yearly depreciation cost of €120 plus let's say about €80 in maintenance giving a yearly cost of €200. The full cost of the car includes tax (€500), insurance (€500), Maintenance (€750) and of course depreciation (we'll go with a second hand car bought for €15000 and used for 7.5 years, so €2000 per year). That adds up to €2500 + €500 + €500 + €2000 = €5500 per year.

    So let's start with removing the car completely: If you could move closer to work so you could walk or cycle, you'd save €5500 per year every year. That means if it costs €50,000 to move house/apartment closer to work, that move will pay for itself in less than 10 years, and save €110,000 over the next 20. It'll probably mean a much higher quality of life too.

    So it's worth comparing the costs of all other options. A price comparison between walking, cycling, driving and public transport looks like this. For walking, I've factored in €50 per year for a new pair of shoes. In reality, walking and cycling will probably save you much more in long term health costs than they will cost. The price of public transport will vary wildly, so let's go with €5 per day * 365 days a year = €1,825 per year:
    CostOfTransportModesWithLifeExpectancyChanges.png

    I was interested in the risks associated with each, so I included the impact each has on one's life expectancy (I trawled a few papers and articles to get these: Life Expectancy Changes with transport modes: One, Two, Three, Four, Five). It looks like there's almost a direct correlation with how little a mode of transport costs, and how it will effect how long you will live. Cheaper modes of transport get their energy from you in the form of exercise, which makes your cardiovascular system more efficient, which makes you live longer. Sedentary modes of transport reverse this process and decrease your life expectancy. Despite the fact that cycling is seen as dangerous, it seems that if you switch to it, your life expectancy actually goes up considerably.

    We have one car in the household, and while I do actually cycle a lot already, I wanted to try a project to try building an electric bike for two reasons: (1) It would cater to the few scenarios I can't currently cycle: carrying full shopping loads or other heavy loads in hilly terrain (2) To see if would be a viable mode of transport for anyone who currently drives everywhere. Many car-dwellers I talk to have the a same reaction: "I see that cycling is way cheaper than driving.. But I haven't cycled since I was seven and I wouldn't be fit enough."

    What about a way to get the best of both worlds? So I decided I'd try a project myself to see how easy it would be: I built an electric bike. To be more accurate, I took a normal bike and fitted an electrically powered front wheel to it. The result was something rather cool: It was easy to do. It makes cycling distances, up hills and with heavy loads significantly easier, and it opens up cycling to just about anyone. It is a genuine alternative to a car.
    ElectricBike7.png

    The Stats
    Cost of converting to an electric bike: €500 ($549) with this kit here
    Savings per year over driving: 3,190.4 kWh per year | €473.05 per year | 724.2 kg CO2 per year.
    Payback Period: 1.06 years (e.g. "No brainer")
    10 Year Savings: €4,230
    10 Year ROI: 746%
    Annuallised Return on Investment: 74.4%

    If you can give up your car entirely, the savings jump to €2723 a year, for a whopping ROI of 5,246% over ten years (€2,723 * 10 years = €27,230 - initial investment of €500 = €26,730)

    Fitting a Bike with an Electric Wheel
    I ordered a 250W Electric Bike Conversion Kit from Dillinger, for roughly €500 / $600. I saw plenty of alternatives on Ebay and Alibaba ranging from €200 - €1000+, but opted for one above the cheapest with a brand which is reasonably well known. Given the Irish weather, this was going to frequently get wet.

    The kit arrived a few days later. This is what it looks like in the box. It includes the electric wheel itself, the 8Ah battery, the battery holder which attaches to the bottle holder mount on the frame, the control unit which attaches to the handlebars, and the cabling to wire it all up:
    ElectricBike2.png

    After putting a (normal) tube and tire onto the electric rim, you fit that onto the front forks like any other wheel:
    ElectricBike3.png

    There was one tricky aspect to this in that the electric motor in the front wheel is wider than most normal wheels @ 100mm wide, and although it's designed to fit inside most bike front forks, if you have front suspension or an unusually wide fork, it won't fit on. You can measure the clearance of your fork in advance. You need 100mm between the forks for 700mm up the forks from where they attach to the wheel - the motor is a disc 100mm across with a diameter of 700mm.

    Next, I added the battery holder and the wiring. The battery holder mounts onto the bottle holder of the bike:
    ElectricBike4.png

    I attached the control unit to the handlebars, along with the brake levers which automatically turn off the motor when they're pulled:
    ElectricBike5.png

    I tidied up the wires with some cable ties, running them to the handlebars up the bottom of the frame with the brake and gear cables. There was some excess length in the cables, so I added a frame bag and tied up all of the loose ends in there so stop them from causing any problems:
    ElectricBike6.png

    And I was all done:
    ElectricBike7.png

    Energy, Cost and Emissions Savings
    The bike came with an 8Ah battery. It holds 150 watt hours (.15kWh), and on this charge, it has a range of about 40km of cycling assistance with reasonably heavy usage (e.g. with weight on the bike and on hilly terrain).
    ElectricBike8.png

    That gives an energy consumption of .15kWh / 40km = 0.0038 kWh per km or 7kWh per year. It doesn't do all of the work and you still need to cycle. At a leisurely pace, it reduces the effort by about 50%, which means I'm also contributing 0.0038 kWh per km, giving a total energy consumption 0.0038 * 2 = 0.0076 kWh per km. In comparison, a Nissan Leaf consumes 0.16kWh per km given it has a 150km range with a 24kWh battery. Our petrol car travelled 11.36 KM/Litre of petrol and 1 litre of petrol contains 10 kWh, so it consumed 0.8803 kWh per km.

    Now that we know the consumption of the electric bike, and a baseline to compare it to (a petrol car), we can work out what we stand to save in terms of energy, cost, and emissions.

    Energy Savings
    The bike consumes 0.0038 kWh of electricity per km, and so with a 10km daily commute, that means cycling roughly 10km per day or 70km per week or 3,640km per year. That's 0.0038kWh * 70km per week = 0.266 kWh per week, and 13.8kWh per year (of which half, or 7kWh, is coming from the electricity grid, and half is coming from your body).
    I'll use a petrol car for comparison. Driving a petrol car this same distance would result in 3,640km * 0.8803 kWh per km = 3,640 * 0.8803 = 3,204.2kWh. That means switching to the electric bike saves 3,204.2 - 13.8 = 3,190.4 kWh per year.

    To put the energy consumption of commuting with this bike in context: 7kWh for the entire year? That means your entire year of work commutes on the amount of energy it takes to run an electric shower for an hour, or to drive a petrol car for 19km:
    CarVersusEBikeYearlyCost.png

    Cost
    The bike battery is charged by plugging it in to a socket, which costs €.17 / kWh, so the total yearly cost is €.17 * 6.9kWh = €1.17.
    Driving the same in a petrol car comes to: @ 11.36 KM/Litre for 3,640km, which consumes 3,640 / 11.36 = 320.42 litres of petrol. Petrol costs €1.48 per litre so €1.48 * 320.42 = €474.22.
    That comes to a financial saving of €474.22 - €1.17 = €473.05 per year, or 0.2% of the cost of driving to work . If you can get rid of your car entirely, it'll save a further ~€1000 in maintenance, ~€500 in road tax, ~€750 in insurance, or €473.05 + €1000 + €500 + €750 = €2723.05 in total a year.

    Emissions
    The Irish grid carbon intensity is about 535g CO2 per kWh, so cycling the bike emits 7kWh * .535 = 3.745kg CO2 per year. Driving a petrol car this same distance would result in 3,640km * 200g CO2/km = 3,640 * .2 = 728kg CO2.
    Hence, converting from driving to work to cycling the electric bike will save 724.2 kg CO2 per year.


    The Verdict?
    What I like about this one is the fact that it opens cycling up as a genuine commuting option to just about everyone. It removes the biggest barriers people have, which is the fear that it will be too difficult for them to cycle any great distance or that they will be sweaty when they arrive in work. An electric wheel essentially allows you to put in as much or as little effort as you like. The end result is a commute costing 0.2% of the cost of driving to work, saving €500 per year and removing 7,242 kg CO2 over its lifetime. I already primarily cycle everywhere, including to and from work, so it's mostly served to (1) make me get places faster, (2) allow much bigger shopping loads to be carried by bike and (3) allowed me to get in and out of town when meeting friends without being sweaty. Pretty useful for the 25% or so of the time I use it.

    Conclusion
    If you are already a hard-core cyclist, an electric bike is an optional luxury. For everyone else, an electric bike represents a way to drastically reduce or remove entirely one's dependence on a car, which is a major step towards removing one of the biggest piece of energy expenditure from your life. With an annual ROI of 74.4%, it beats any stock market investment I could make with the €500 cost. Glad I tried this one out!


  • Registered Users Posts: 21,594 ✭✭✭✭ ted1


    With regards the gas calculations for the Windows you didn't allow a drop in usage for summer months. To give a true payback you need to make correct allowances.


  • Registered Users Posts: 1,065 ✭✭✭ Kash


    Absolutely loving following this thread. I've installed the radiator reflectors over the weekend, I also picked them up cheap in Lidl a few months ago. We disconnected our oil fired central heating a couple of years ago and switched to a solid fuel stove. The radiators aren't very efficient, and I need to look into alternative heat sources for when we have no fire lit, but we're very happy with the stove.


  • Registered Users Posts: 263 ✭✭ Conor20


    ted1 wrote: »
    With regards the gas calculations for the Windows you didn't allow a drop in usage for summer months. To give a true payback you need to make correct allowances.

    Yep - my knowledge of thermo-dynamic modelling extended as far as reading the relevant Wikipedia pages when I was figuring out the relative savings of installing Double Glazed Windows vs Attic Insulation vs Internal or External Wall Insulation vs a Wood burning stove vs Solar PV to rank them from best to worst, so some of the calculations may be simplistic. At the same time, I think they are within the right order of magnitude relative to each other, so should rank them correctly. I'm learning a lot as I go having now implemented several projects (Radiator Heat Reflectors, Double Glazed Windows, Rubber Seals around doors connecting to the outside, Wood Burning Stove with Back Boiler) so I'll get better at the modelling aspect with each project implemented. If nothing else, it's been a great learning experience. Understanding energy consumption and generation hasn't been half as intimidating as it would seem from the outside.


  • Registered Users Posts: 263 ✭✭ Conor20


    Kash wrote: »
    Absolutely loving following this thread. I've installed the radiator reflectors over the weekend, I also picked them up cheap in Lidl a few months ago. We disconnected our oil fired central heating a couple of years ago and switched to a solid fuel stove. The radiators aren't very efficient, and I need to look into alternative heat sources for when we have no fire lit, but we're very happy with the stove.

    Great, thanks! Keep it up! We have also made the switch to a wood burning stove, with a back boiler to heat the house, and it's definitely been a great move. I have been waiting to post about it until I have concrete figures for the financial and kWh savings, but it has exceeded my expectations so far, and it really made the sitting room cosy over the winter.


  • Registered Users Posts: 263 ✭✭ Conor20


    While I cycle to work and most other places, the other half is reluctant to become a carless household. This means we need to find a way of achieving motorised transport without significant expense and emissions. I expect this is a universal hope across most households, so let's get it worked out. Since we started the journey to energy independence - freeing ourselves from fossil fuels, and energy bills in the process, one of the main aims was to get away from oil powered transport. Very happily, this is now a reality. We'll never be going back to a fossil fuel car!

    NissanLeafSmallSize.png

    The Payback analysis:
    • Cost of the Leaf: €16,000
    • Cost to run the petrol car yearly: €3250.56
    • Cost to run the Leaf yearly: €295.76
    • Savings: €2,954.8 per year | 11,224 kWh per year| 1630 kgCO2 per year
    • Payback Period: 5.4 years
    • 10 year payback: €7,548 (from baseline of current gasoline car, allowing for a new battery after 5 years costing €5000 and €1000 of maintenance costs, and assuming a depreciation of the entire value of the car over 10 years)
    • 10 Year Return on Investment: 40.7% (Total cost = €21,000, Total savings = €29,548)
    • Annualised Return on Investment: 4.1%

    How it's worked out
    Way back in the initial look at home energy consumption, the breakdown of energy costs came to this: Heating our average house consumes 29kWh per day. Powering the house's electronics consumes 13kWh per day, but the car.. That consumes a whopping 40kWh per day! So if you drive a petrol / diesel powered car, then this energy spend is enemy number one - a whopping 40kWh per day!
    EnergyCostPerYearBreakdownByCarHeatElectricity.png

    The car consumes a disproportionate amount of energy for a few reasons:
    1. Cars weigh 1500kg+, you weigh less than 100kg. Most of the petrol in the tank is consumed moving the metal that surrounds you rather than you. (Hence, if you want to be truly efficient, then cycle {LINK TO Transport Costs and Energy Consumption}.. If you can't cycle, then drive an electric car).
    2. Internal Combustion Engines are only 10-15% efficient. That means 85% of the gas you pump into your car's fuel tank is turned into heat and noise which is of no use. The more efficient cars turn 15% of the chemical energy in the fuel into forward momentum when you depress the accelerator. But only if the engine is at the optimum temperature. That means short journeys are particularly expensive in terms of $ / km - when the engine is warming up, it consumes significantly more fuel.
    3. "Normal" non-electric/hybrid cars don't use regenerative breaking. That means that once the engine has ignited enough petrol or diesel to power the car forwards, when you stop at a traffic light, all of that energy is dumped into the brake pads as useless heat, and the process starts again with that energy removed from the equation.
    4. Certain driving styles consume far more gasoline than others, but most people don't know this. Internal Combustion Engines rarely give any feedback to the driver of their fuel economy so the cars tend to be driven inefficiently.

    From an energy point of view, this just won't do! Wouldn't it be great if when you hit the brakes, the engine ran in reverse and started pumping fuel back into the fuel tank. But there is! It comes in the form of a Lithium Ion battery. An electric vehicle removes these inefficiencies, to use the money you pump into the car in the form of electricity into far more efficient momentum.

    The Battery Revolution
    Battery technology is experiencing an explosive growth as transport and renewable energy companies pour money into research in the area. The range of the Nissan Leaf has gone from 110km / 70 miles in 2011 to 150km / 93 miles in 2014, to 172km / 107 miles in 2016 and a projected 500 km (310 miles) for the 2017 model. Nissan have increased the storage of the Leaf battery from 24kWh (2011 to 2014) to 30kWh (2016) to 60kWh (2017) in the same amount of space inside the vehicle. It's obvious that battery density per unit space is experiencing its own Moor's Law. I suggest reading the fantastic Wait But Why article on Tesla and the Battery Storage Revolution to understand the monumental change that will bring in terms of removing people's dependence on fossil fuels and the associated costs.

    For me, this meant moving to an electric car. Like everything on this thread - this was an investment intended to create a mutually beneficial situation in terms of personal wealth creation, and environmental impact reduction.

    Cost / Payback Analysis
    First the baseline cost of running our current car
    Cost Baseline: To work out the cost and energy savings, I started with the weekly millage of about 300km per week (if you drive more, then an electric car will pay for itself faster). Our previous car was a 15 year old 1.4 litre Nissan Almera, from which we were getting 32 MPG (UK Gallons). Converted to km per litre, that's is 11.36 KM/L (or 8.8 Litres per 100KM). So 300km driven per week / 11.36KM/L = 26.4 litres of petrol per week. That's about 1372 litres per year. Petrol ranges from 1.259 €/Litre to 1.698 €/Litre in Ireland for the last few months, so taking the average of €1.48 per litre means €1.48 * 1372 = €2030.56 ($2200 per year). Another cost factor was the average of €1100 I was spending in maintenance on average, each year for the last 5 years - the car generally ran well, but something tended to go in the engine or gear box each year. Finally, in Europe, cars are taxed according to emissions. The tax on the Almera came in at €570 per year. All in, it cost €2030.56 + €1100 + €120 = €3250.56 to run the petrol car.

    Emissions Baseline: The Almera's stated emissions was 158g CO2/km, however given what's come out from VW's emissions testing and about the tests themselves, I'm going to bet this was atleast 200g CO2/km. At 250km per week or 13,000km / year, that means the emissions were 200g * 13,000km = 2600kg CO2.

    Energy Consumption (kWh) Baseline: Finally, 1 litre of petrol contains 10 kWh. 1372 litres a year means 1372 * 10 = 13,720 kWh per year.

    So now I knew what I was using, I was able to estimate the potential savings to evaluate this investment. After some scouting, I found a second hand Black 2014 Nissan leaf Acenta with 5000km on the clock for €16,000. While I live here in Ireland, the UK has a significantly bigger second hand car market. Usually, there would be an import tax of around €5k to import a car to Ireland, which car dealers in Ireland lobbied the government to introduce to protect their trade. However, I realised this tax is based purely on tailpipe CO2 emissions. The Nissan Leaf has zero tailpipe emissions. Huzzah! Importing the car was free. So that was a good start.

    Estimating the running costs of the Nissan Leaf
    Cost Estimate: Firstly, the road tax of €570 drops to the lowest emissions category for the Leaf: €120 per year.
    Because the Leaf on sale was only 8 months old, it was still warrantied for 5 years, so no significant maintenance cost for the next 5 years. We replace the petrol from petrol stations with electricity from our house, and from public charging stations. Funnily enough, all public charge points in Ireland are completely free, and I'm lucky enough to live within 2km of two fast charge points. So it would actually be possible (and I know several people who do) drive with no energy costs whatsoever, but let's work out a baseline based on charging at home.
    We drive roughly 300km per week. The range of the Leaf is 150km and has a 24kWh battery pack. That means it will consume 48kWh per 300km, and hence 48kWh per week. We had a smart electricity meter installed by our utility when we got the electric car which allowed us to move to a day / night rate of €0.17 / kWh during the day and €0.07 at night. Hence, charging will cost 48kWh * €0.07 = €3.36 per week, or 3.38 * 52 = €175.76 per year. That is a somewhat incredible saving of €2030.56 (which it cost to run the petrol car) - €175.76 = €1854.8 per year.
    So the yearly cost of the Leaf is €120 + €175.76 = €295.76.
    In total, that means the Leaf saves €3250.56 - €295.76 = €2954.8 per year.

    Energy Consumption (kWh): The leaf has a 150km range, and a 24kWh battery. That means we'll be consuming 48kWh driving 300km per week, or 48 * 52 = 2,496 kWh per year. Our petrol car consumed 13,720 kWh to drive this far, meaning the electric car uses 2,496 / 13,720 = 0.1819 or 18.1% of the energy to drive the same distance. The electric car will save 13,720 - 2,496 = 11,224 kWh per year to drive the same distance.

    Emissions: The emissions of an electric car are no longer due to the combustion of petrol in the engine. They're due to the generation of electricity in the power stations from which you draw power. That means they could vary from virtually zero if charged from solar, wind or nuclear, to close to that of a lower-emitting petrol car if the electricity is generated by coal power stations. The electricity grid emissions for Ireland are posted online in real time by Eirgrid here. This is today's picture:
    GenerationMakeupOfTheIrishElectricityGridAtTimeOfWriting.png
    So, today the electricity generation is 389 gCO2 / kWh. At this level, driving 300km per week, which consumes 48kWh results in 48 kWh * .389 gCO2 / kWh = 18.67 kgCO2 per week, or 18.67 * 52 = 970.9 kgCO2 per year. Our petrol emitted 2600kg CO2 to drive this same distance, so the yearly emissions savings is 2600 - 970 = 1630 kg CO2 per year.

    Car Rental to cover long journeys
    One extra factor that I considered here is the cost of renting a petrol car for longer journeys. The west of Ireland has some of the best surf (due to having some of the worst weather!) in the world, and so we drive to remote parts of the west 4-5 times a year. It costs about €50 to rent a car for a weekend off peak, so this would come to about €250. However, we're surrounded by family and friends who like driving the Leaf, so I think we'll just be able to swap cars when this is required. It's certainly an option however for people without this option. If we're saving in the region of €3k per year with the electric car, it would likely still financial make sense for people who need to drive long distances into areas not covered by charging infrastructure to move to an electric car for their commuting and city driving, and to rent a petrol car for the longer trips.

    Our experience with the Leaf so far
    In summary, the Leaf has worked out very well so far indeed. We haven't had any problems, the driving experience is far superior to our old petrol car with increased acceleration, more reliable handling, on-board electronics (things like rear facing camera for reversing with augmented reality overlay of where the car will end up, the car is internet connected, excellent heating / cooling systems), and we're saving a considerable amount of money on energy. It's led to some further benefits around understanding our energy usage and moving our other appliances to the night time electricity rate. We haven't run out of battery yet, and I don't expect that we will. After buying the electric car, I came to the conclusion that Range Anxiety was invented by motor-media reviewers to have something negative to say about electric cars. No one runs out of petrol on the side of the road. That's because they plan their journey and gas station stops around the range limitations of the petrol tank. The same holds true for an electric car - you simply plan your journey in such a way that you don't drive somewhere further away from somewhere you can charge than you have range left in the battery. 99% of our journeys are less than 150km anyway, so we mostly don't have to worry about it at all - we just charge the car at night when we're asleep. This holds true for probably 95% of urban dwellers.

    For longer journeys, the electric car charging network is pretty good in Ireland:
    MapOfElectricVehicleChargingInfrastructureInIreland.png

    From keeping up with EV owners in Ireland, there certainly have been some teething problems, but the motorway network is well built out with fast chargers, so it's possible to drive most places in the country using these. The fast chargers charge the Leaf to 80% in about 20 minutes from empty. The charging network is currently completely free, and it seems it will be so for at least the next year. We've mostly charged at home, and so I calculated the above running costs exclusively charging at home, but each charge from one of these points reduces some of the running cost. We’ve had some opportunities to charge in some nice places. You may recognise Lahinch, Co Clare from the Big Wave surfing documentary Wave Riders:
    EVChargerInLahinchCoClare.png

    As of the December 2015, the car has had 39 fast charges and 518 slow charges. The Leaf Spy app gives very granular information into the health of the batteries:
    LeafSpySmallSize.png

    It reads the battery capacity at 90%, although that varies from 88% - 95% depending on the temperature of the battery when it was measured. An interesting point about electric cars is that there are very few moving parts to break. In fact, the only thing that will likely need replacing at the traditional "end of life" of a car will be the battery. That means, as battery technology develops, I can simply replace the battery with the latest model, increasing the range of the car and essentially giving it a new lease of life until the next battery upgrade. This currently costs about €5000. I suspect that we'll need to replace the battery after about 5 years. Going by the current battery density development of new Leafs, in 2019, the density will have gone from 24 kWh (150km range) to perhaps 100 kWh (600km range).

    There have been a few other added bonuses:
    • The Nissan leaf is an energy nerd's best friend in just about every way. The dashboard screen gives you granular energy consumption charts at the click of the screen. As we already know, if you can't measure it, you can't reduce it, so this feedback is invaluable to reduce energy consumption of your driving. Even the heater employs a heat pump rather than electric resistance heating to squeeze another 10km of range from the battery in cold weather.
    • It's great to no longer be pumping pollution and particulate shown by the World Health Organisation to cause cancer, particularly in children, into the air my children and the people around me are breathing.
    • I can now log into my car from my phone to turn on and off charging, turn on de-icing and climate control.
    • We had a smart electricity meter installed by our utility when we got the electric car which allowed us to move to a day / night rate of €0.17 / kWh during the day and €0.07 at night. We immediately moved all of our programmable appliances to run during the night hours - watching machine, dishwasher, etc.
    • When I install Solar PV, I will have 24 kWh of storage connected whenever the car is there. That's enough to power the house for two whole days, or a few more if we're careful, if we install an inverter.

    We went for a nearly new Leaf, because of the slightly longer range compared to older models, but I see 2011 Nissan Leaf models on the market in Ireland and the UK for about 50% of what I paid. The same is likely true in the US and other places around the world. If you currently have two fossil fuel powered cars, and your daily commute is, under 70km per day, then replacing one car with an older used Leaf would give a payback of 3.38 years @ 300km driving per week.

    The Summary
    This is a serious coup as an energy investment towards energy freedom. We haven't been to a petrol station in over a year. We're saving €2,954.8 per year with a 11,224 kWh reduction in energy use, and saving 1,630 kgCO2 per year in the process. At this stage, we've switched to all LED lights, installed insulation, installed a wood burning stove (next post!) and switched to an electric car, the money is starting to stack up pretty fast into our energy savings fund. We’re well on our way to energy independence! Viva le progress!


  • Registered Users Posts: 1,296 ✭✭✭ atilladehun


    great work. well done.


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  • Registered Users Posts: 1,502 ✭✭✭ macnab


    I am a Leaf owner also, on my second Leaf now. My last Leaf was a 2011 generation 1 model with 24kw. 90km was the most I ever drove on a single charge with 10km remaining. The battery was down to 85% after 80,000km of use in its 5 years. I have a 48km each way commute where I can charge at work. By my calculations the battery was going to last at least 11 years of my type of useage.
    The Leaf I drive now is a generation 1.5 with the 30kw battery. The chemistry of this battery has been altered from the generation 1 model to reduce degradation. There are reports of 2014 reg Leafs with 99% battery health which is amazing compared to the generation 1 battery.
    My point being that allowing 5 years for your Leafs battery until it needs replacement is very pesimistic. I would not enter it into cost calculations at all, unless you are going to balance it with a complete engine rebuild of an internal combustion engine.
    So there's €5000 back for you :-)
    BTW I also built an electric bike and regularly do the 90km round trip to work on it.
    I am really enjoying your thread, keep up the good work.


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