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PV solar panel in ireland

  • 05-03-2010 5:48pm
    #1
    Closed Accounts Posts: 90 ✭✭ YourSQL


    How many KWh a year can one expect from a 100w solar panel for example in a year in ireland? excluding inverter losses and that sort of thing. Solar panels seem to have gone down in price a bit, I seen them for 200GBP now and not much interest in them these days with the recession & somewhat reasonable oil price.

    but of course global warming + increasing oil prices will make it more viable to install them. unless you believe the theory that global warming will just make ireland permanently overcast


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Comments

  • Moderators, Science, Health & Environment Moderators Posts: 6,367 Mod ✭✭✭✭ Macha


    This link should give you a few details, although it's UK not IE:

    http://www.lowcarbonbuildings.org.uk/Microgeneration-Technologies/Solar-photovoltaic-PV
    Prices for PV systems vary, depending on the size of the system to be installed, type of PV cell used and the nature of the actual building on which the PV is mounted. The size of the system is dictated by the amount of electricity required.

    For the average domestic system, costs can be around £5,000- £7,500 per kWp installed, with most domestic systems usually between 1.5 and 3 kWp. Solar tiles cost more than conventional panels, and panels that are integrated into a roof are more expensive than those that sit on top.

    A 2.5kWp array can provide enough electricity to meet around half a households electricity needs, this means a saving of around £250 a year.

    If you intend to have major roof repairs carried out it may be worth exploring PV tiles as they can offset the cost of roof tiles.

    Grid connected systems require very little maintenance, generally limited to ensuring that the panels are kept relatively clean and that shade from trees has not become a problem. The wiring and components of the system should however be checked regularly by a qualified technician.

    Stand-alone systems, i.e. those not connected to the grid, need maintenance on other system components, such as batteries.


  • Closed Accounts Posts: 2,948 gizmo555


    taconnol wrote: »
    For the average domestic system, costs can be around £5,000- £7,500 per kWp installed, with most domestic systems usually between 1.5 and 3 kWp. Solar tiles cost more than conventional panels, and panels that are integrated into a roof are more expensive than those that sit on top.

    A 2.5kWp array can provide enough electricity to meet around half a households electricity needs, this means a saving of around £250 a year.

    £12,500 to £18,750 capital outlay to save £250 a year? Ouch!


  • Closed Accounts Posts: 90 ✭✭ YourSQL


    gizmo555 wrote: »
    £12,500 to £18,750 capital outlay to save £250 a year? Ouch!

    those prices seem unusually high and probably include paying people to install it for you, which is probably not a good idea if you want the system to pay off in your lifetime.

    installing PV solar panels still has a much lower yield than getting rid of frequently used incandescent blubs or solar water heating but apparently grid-parity is being reached in some of the sunnier european countries now and it should be our turn soon.

    was also thinking of getting a 20-30W panel just to run my server + modem during the day and use the normal transformer by night (no inverter, just a small controller circuit)


  • Closed Accounts Posts: 2,948 gizmo555


    YourSQL wrote: »
    those prices seem unusually high and probably include paying people to install it for you, which is probably not a good idea if you want the system to pay off in your lifetime.

    A lot of people, including me, would be nervous of doing DIY electrical installations - I'd be afraid of shortening my lifetime! :)
    YourSQL wrote: »
    installing PV solar panels still has a much lower yield than getting rid of frequently used incandescent blubs or solar water heating but apparently grid-parity is being reached in some of the sunnier european countries now and it should be our turn soon.

    Could be - think I'll just wait for our turn to come round though. It's not an area in which it will pay to be an early adopter. Realistically, for the moment, PV only makes sense where for one reason or another you're offgrid.
    YourSQL wrote: »
    was also thinking of getting a 20-30W panel just to run my server + modem during the day and use the normal transformer by night (no inverter, just a small controller circuit)

    Well, the likes of Maplins have plenty of panels in that sort of size at prices that wouldn't break the bank. Still can't see how you'd recover the cost, though.


  • Closed Accounts Posts: 90 ✭✭ YourSQL


    gizmo555 wrote: »
    A lot of people, including me, would be nervous of doing DIY electrical installations - I'd be afraid of shortening my lifetime! :)



    Could be - think I'll just wait for our turn to come round though. It's not an area in which it will pay to be an early adopter. Realistically, for the moment, PV only makes sense where for one reason or another you're offgrid.



    Well, the likes of Maplins have plenty of panels in that sort of size at prices that wouldn't break the bank. Still can't see how you'd recover the cost, though.

    the smaller grid tie inverters just plug into an ordinary socket so its not a big deal to install. the hardest part would be to fix them to the roof and making sure they stay there.

    maplin sells the most overpriced solar panels going. a 100w panel there costs around 1k. i know someone who got an 18 watt one there for well over 100e. if i could get a decent 30w panel for about 40e as I have seen them for on ebay and run the server off it during the day it would pay off in a few years if it pumped out anywhere near the 30w on a good day but those panels could well have been crap. i wouldn't trust any of the ones from chinese sellers anyway


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  • Registered Users Posts: 1,627 ✭✭✭ quentingargan


    To answer the OPs question, you can download free simulation software from Retscreen in Canada - its an excel worksheet with different locations. There is quite a difference between Wexford and Donegal, but in broad terms you can expect up to about 1kwHr per year per watt installed. If you want to send your location I can run the model on Retscreen, but the software is interesting in itself.

    The UK has just introduced fantastic feed in tariffs for solar PV - over 40p per KwHr for electricity produced. They did that in Spain a couple of years back to build the industry, but I am not convinced that this is a good move for countries where solar will always be at a disadvantage to wind where electricity generation is concerned.

    There are a few of us in Ireland who have qualified as City & Guilds PV installers and then never did a single installation (you can do the training at North West Regional College in Derry). Solar PVs in Spain made sense at a feed in tariff of 45c per KwHr. The building programme sort of stalled when the price fell to 31c. For our sunshine that would require about 60c in Ireland for the same return on investment. I agree .... OUCH!

    But money isn't everything, and some folks spend a lot of money on their cars, others spend a lot of money wanting to know that their electricity came from the light and not from the dark.

    Suppliers need to move with the times. Module prices ex-factory have halved in the last two years. Installations haven't.


  • Closed Accounts Posts: 90 ✭✭ YourSQL


    To answer the OPs question, you can download free simulation software from Retscreen in Canada - its an excel worksheet with different locations. There is quite a difference between Wexford and Donegal, but in broad terms you can expect up to about 1kwHr per year per watt installed. If you want to send your location I can run the model on Retscreen, but the software is interesting in itself.

    The UK has just introduced fantastic feed in tariffs for solar PV - over 40p per KwHr for electricity produced. They did that in Spain a couple of years back to build the industry, but I am not convinced that this is a good move for countries where solar will always be at a disadvantage to wind where electricity generation is concerned.

    There are a few of us in Ireland who have qualified as City & Guilds PV installers and then never did a single installation (you can do the training at North West Regional College in Derry). Solar PVs in Spain made sense at a feed in tariff of 45c per KwHr. The building programme sort of stalled when the price fell to 31c. For our sunshine that would require about 60c in Ireland for the same return on investment. I agree .... OUCH!

    But money isn't everything, and some folks spend a lot of money on their cars, others spend a lot of money wanting to know that their electricity came from the light and not from the dark.

    Suppliers need to move with the times. Module prices ex-factory have halved in the last two years. Installations haven't.

    1kwh is still not bad, does that include any transmission loss? would mean less than 10 years to pay back unless the price of electricity goes down but that seems unlikely. i'll try downloading the thing later


  • Closed Accounts Posts: 2,948 gizmo555


    But money isn't everything, and some folks spend a lot of money on their cars, others spend a lot of money wanting to know that their electricity came from the light and not from the dark.

    That's a fair enough point, Quentin. It's rare though, to see any accounting for the embodied energy and CO2 in solar systems, whether PV or hot water, when analysing their nett environmental benefit. Does Retscreen account for this or are there any other reasonable figures publicly available which one could use?


  • Registered Users Posts: 1,627 ✭✭✭ quentingargan


    gizmo555 wrote: »
    It's rare though, to see any accounting for the embodied energy and CO2 in solar systems, whether PV or hot water, when analysing their nett environmental benefit. Does Retscreen account for this or are there any other reasonable figures publicly available which one could use?
    I have often heard it said (and blithely repeated it myself without checking) that it took more energy to produce solar PVs than they give back in their lifteime. In Ireland, it may take more money, but that's a different matter.

    Of course, a PV will produce about half the energy in Ireland that it would in parts of Spain, so the energy payback may double. On the flip side, our electricity production is a lot more carbon intensive than it is in other countries. We are at 620g/Kwhr compared to 430g in the UK.

    In 2004, the National Renewable Energy Laboratory in the USA produced this document, suggesting at the time that solar PVs had an energy payback time of just 2 years. In Ireland you could maybe double that, but then again, solar panel production has become a lot more efficient in the meantime.

    According to wiki, the energy payback time was estimated at 8 - 11 years in 2000, but more recent studies reduced this to between 1.5 and 3.5 years, with thin film even lower. I guess you could double all that for Ireland.

    I did do a "back of an envelope" estimate for solar water heating some time ago, measuring CO2 production for steel, aluminium, glass, processing etc., and came to the conclusion that it was less than two years. I've seen documents claiming less than 1 year, but again that depends on local climate.

    Also, that would depend on whether the system is displacing electricity, or a modern gas-fired condensing boiler, or even a "zero carbon" wood chips / pellets, but of course unless you cut your firewood with your teeth, nothing is zero carbon.


  • Closed Accounts Posts: 2,055 probe



    Of course, a PV will produce about half the energy in Ireland that it would in parts of Spain, so the energy payback may double. On the flip side, our electricity production is a lot more carbon intensive than it is in other countries. We are at 620g/Kwhr compared to 430g in the UK.

    By way of perspective:

    Carbon intensity g CO2 per kWh:

    Norway 5g (98% renewable)
    Sweden 17g (47% renewable, 45% nuclear)
    Brazil 50g (83% renewable)
    France 88g
    Argentina 307g
    Japan 365g
    Italy 429g
    Spain 485g
    US 611g
    Czechia 742g
    India 805g
    China 868g
    Australia 891g
    ZA 920g
    Poland - weighing in at over 1kg (1005g) - at least they don't have any nuclear in the mix - which is unusual for an ex Soviet empire country.


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  • Closed Accounts Posts: 224 ✭✭ Cheeble


    I use this, though I've not bothered to find out it's provenance....

    http://re.jrc.ec.europa.eu/pvgis/apps/pvest.php

    Cheeble-eers


  • Registered Users Posts: 229 ✭✭ Skr4wny


    Folks, came to this thread through google. Does anyone know what the situation with PV panels these days? Everywhere online only seems to be selling solar heating in Ireland.

    Thanks.


  • Registered Users Posts: 1,627 ✭✭✭ quentingargan


    Skr4wny wrote: »
    Folks, came to this thread through google. Does anyone know what the situation with PV panels these days? Everywhere online only seems to be selling solar heating in Ireland.

    Thanks.
    Main reason is that the feed in tariff in Ireland for exporting unused electricity is abysmal compared to other countries. (9c per KwHr here).

    You can store hot water, but batteries are an expensive way to store electricity.


  • Registered Users Posts: 121 ✭✭ dardhal


    The greatest problem is not feed-in tariffs or other kinds of subsidies. The problem in Ireland is the weather, that makes most PV installations in Ireland financially suicide and/on of little practical use. The very short days during winter and the very dull days , with lots of clouds all year round,makes for PV not effective or economically sound here (check http://re.jrc.ec.europa.eu/pvgis/ for estimates on how much production you may get).

    Although PV panels are now extremely cheap compared to only some years ago (you may be able to buy retail quantities by 1€/Wp or close), inverters and specially batteries for storage are as expensive as they used to be, but the big issue is KWh production, which unfortunately here can't be very good.

    I guess companies stock whatever they feel they can sell, and selling PV in Ireland, is a hard task. For the same reason there are not (many, any?) outdoor pools here, and other countries in the southern part of Europe have thousands of them. However, Ireland could have a great potential for wind power (already been exploited) and biomass coming from the vasts extensions of pastures, meadows, forests and the like.


  • Registered Users Posts: 24 ✭✭✭ brendanf


    I would have agreed with you a couple of years ago Dardhal re PV but it has become so cheap that it offers a serious alternative to wind in a domestic scenario - With a 5kW system you should be guaranteed a minimum of 4250kWhrs per year, no servicing required either....mind you 80% of power produced is between April - September so ESB smart meter is the way to go...I would avoid batteries like the plague!


  • Registered Users Posts: 121 ✭✭ dardhal


    brendanf wrote: »
    I would have agreed with you a couple of years ago Dardhal re PV but it has become so cheap that it offers a serious alternative to wind in a domestic scenario - With a 5kW system you should be guaranteed a minimum of 4250kWhrs per year, no servicing required either....mind you 80% of power produced is between April - September so ESB smart meter is the way to go...I would avoid batteries like the plague!

    I still can't see it as economically viable. Even if yo manage to only spend 5000€ on that 5 KWp worth of panels and kit (which is a huge "if", considering the inverter alone can be 1000€) because you can design, install and operate the thing yourself (don't know if there are any legal requirements in Ireland for PV installations, even if they are not connected to or never feed electricity to the grid, so if you need a qualified electrician to sign the paperwork, expect the price to go up significantly).

    The problem, which is shared with any other non-dependable, reliable or "schedule-able" source of energy is, you have to spend that energy when it is available. And what can you do with 20 KWh those rare days the sky is bright and days are long, just heat water in the immersion tank? Take advantage of the sunny day and rush to home and start a couple of dishwasher and washing/drying cycles, to avoid wasting energy?

    In the end you still have to be connected to the grid, and even f you manage to do something useful with every one of those 4250 KWh, that is going to be around 600€/year , versus a parts bill that is going to be at least ten times as much. And for getting some hot water, there isn't much point going the PV route, as you will have much more energy from the sun be put into the hot water tank by using much simpler and affordable thermal collectors (and on top of that, less roof real estate gets used, as thermal panels are 50-80% , while PV are 17% efficient tops).

    For sunny countries and regions, you can add a "little" battery to the mix, and so you can buffer daily electricity generation to be used during evening / night, even if the batteries can't buffer electricity on the longer term (they only have capacity for one day). But then having 300+ sunny days a year, it is not a big problem if you have to resort to the grid 20% of the days, as the little battery can improve the effectiveness of the whole system tenfold. But for a region with 300+ non-sunny days, adding short-term storage batteries is an expense that simply doesn't pay.

    Ireland could do very well with larger utility-size wind generation spots all over the country, and using utility-size storage mechanisms or generation management to cover electricity usage. Unfortunately the weather here is not very good for real distributed generation, at least not as long as there is no affordable means of storing electricity longer term.

    However, my opinion isn't worth the HTML it is printed on, and what counts is doing a real world study of each potential customer, because even with this uncooperating weather there may be some economic sense to some deployments.


  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 91,390 Mod ✭✭✭✭ Capt'n Midnight


    If you are going standalone PV then you'll need battery backup.

    If you have battery backup then you could store night rate electricity and use in the day.

    So when costing standalone PV don't use the daytime rate of a unit of electricity



    Other costs
    https://www.electricireland.ie/ei/residential/price-plans/low-user-standing-charge.jsp
    Electric Ireland will introduce a Low User Standing Charge from 1st February, 2012.

    The charge will only apply to a minority of customers who use an average of 2 units (2kWhs) or less per day in any billing period (typically 61 days). Standing Charges will be increased by 15.5 cent (incl. VAT) per day or €9.45 (incl. VAT) per two monthly bill.

    https://www.electricireland.ie/ei/residential/price-plans/other-service-charges.jsp NB Disconnect and Reconnect fees.


    Big rule of thumb, if going for standalone PV consider spending half the budget on replacing existing appliances with low power ones


  • Registered Users Posts: 1,627 ✭✭✭ quentingargan


    If you are going standalone PV then you'll need battery backup.

    If you have battery backup then you could store night rate electricity and use in the day.

    ....

    Big rule of thumb, if going for standalone PV consider spending half the budget on replacing existing appliances with low power ones

    Cycling batteries costs at least 11c per KwHr, so charging them at night and using them by day doesn't work out alas.

    If you use electricity during the day, great - PVs will save you the daytime retail price of electricity and it may stack, especially in commercial situations where you can size a PV array to meet your baseload power requirement. Its also nice to have clean electricity and some people are willing to pay a bit more for that.

    Agree with replacing appliances. We bought one of those little energy monitor plug/socket devices and checked an old fridge we were using. Replaced the fridge a week later. Some old fridges and freezers are guzzlers.:eek:


  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 91,390 Mod ✭✭✭✭ Capt'n Midnight


    Cycling batteries costs at least 11c per KwHr, so charging them at night and using them by day doesn't work out alas.
    11c that's getting close to it actually being practical

    In Ireland PV takes a very long time to break even on investment. Overall PV prices have fallen 7% a year for the last 30 years and there are plenty of lab proven technologies waiting to be commercialised, and economy of scale benefits for this to continue for quite a while yet, if not accelerate.

    In India PV is becoming cost competitive with diesel generators for some applications.

    If you invest heavily in PV now you won't get all the carbon savings you might think since over their life renewables will become more important in our electricity supply too.



    Of course the killer app is cheap storage :)


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


    dardhal wrote: »
    The greatest problem is not feed-in tariffs or other kinds of subsidies. The problem in Ireland is the weather, that makes most PV installations in Ireland financially suicide and/on of little practical use. The very short days during winter and the very dull days , with lots of clouds all year round,makes for PV not effective or economically sound here (check http://re.jrc.ec.europa.eu/pvgis/ for estimates on how much production you may get).

    Although PV panels are now extremely cheap compared to only some years ago (you may be able to buy retail quantities by 1€/Wp or close), inverters and specially batteries for storage are as expensive as they used to be, but the big issue is KWh production, which unfortunately here can't be very good.

    I guess companies stock whatever they feel they can sell, and selling PV in Ireland, is a hard task. For the same reason there are not (many, any?) outdoor pools here, and other countries in the southern part of Europe have thousands of them. However, Ireland could have a great potential for wind power (already been exploited) and biomass coming from the vasts extensions of pastures, meadows, forests and the like.

    So wrong !! The weather can be bad for several days - as it just has been with a week of darkness - but today sunny all day so production was good, washing machine on, heated towel rail heated etc. etc. All free! We did over 2000kwh last year which was a terrible year for sunshine and that is only 2.6 kw installed. You can have 6 kw so at the current prices and the fact the panels last forever it is hardly financial suicide. 6KW of panels on a dull sunless day would give you about 1 kw which will keep your house ticking over for nought.
    Not as good a financial return as other countries but when the power prices get too high the solar system looks very attractive.


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  • Registered Users Posts: 229 ✭✭ Skr4wny


    freddyuk wrote: »
    So wrong !! The weather can be bad for several days - as it just has been with a week of darkness - but today sunny all day so production was good, washing machine on, heated towel rail heated etc. etc. All free! We did over 2000kwh last year which was a terrible year for sunshine and that is only 2.6 kw installed. You can have 6 kw so at the current prices and the fact the panels last forever it is hardly financial suicide. 6KW of panels on a dull sunless day would give you about 1 kw which will keep your house ticking over for nought.
    Not as good a financial return as other countries but when the power prices get too high the solar system looks very attractive.

    And given peak oil is a reality we will have to face sooner than people expect, I think all the break even calculations people make are very short sighted. Once you pay for your renewable setup (wind, solar PV, solar thermal etc), it's there so you have automatic savings on your bills for good, bar maybe some maintenance every now and again.


  • Closed Accounts Posts: 443 ✭✭ Pure_Cork


    If anyone is interested in PV I can get good deals on major brands of inverters through the company I work for, just send me a PM.


  • Registered Users Posts: 121 ✭✭ dardhal


    freddyuk wrote: »
    So wrong !! The weather can be bad for several days - as it just has been with a week of darkness - but today sunny all day so production was good, washing machine on, heated towel rail heated etc. etc. All free! We did over 2000kwh last year which was a terrible year for sunshine and that is only 2.6 kw installed. You can have 6 kw so at the current prices and the fact the panels last forever it is hardly financial suicide. 6KW of panels on a dull sunless day would give you about 1 kw which will keep your house ticking over for nought.
    Not as good a financial return as other countries but when the power prices get too high the solar system looks very attractive.

    Something that most, if not all, private household PV deployments lack is a solid, public and justified long-term cost analysis. I am glad you are happy with your setup, but "only 2.6 KWp" installed turns quickly into a 4000€ setup bill for the regular Joe, and then you still have to pay the monthly standing charge to ESB/whoever. At 2000 KWh/year return from the system, and 15¢/KWh at current prices, that's 300€/year theoretical savings in your electricity bill, at a set up cost of 4000€+

    And I am also very glad you can keep the house ticket at just one 1 KWh/day, but if you can get the house moving at that little consumption, what's to worry about the electricity bill?

    In Ireland, and as long as you have to be connected to the grid, there is little, if any, economic sense for most people. DIY guys that can manage to source panels at bargain basement prices and can manage to do the installation themselves is a whole different story. But for 99% of Irish dwellings and people, is a no go.

    If there were a "net balance" law in Ireland that rewards customers feeding KWh in the grid (either being charged on the difference between KWh used and KWh fed, or by being discounted a given amount for each KWh fed to the grid) that could change a lot. And this wouldn't be a "subsidy" or similar, it is just that fed KWh are as good as utility ones, with the advantage that distributed generation makes load on utilities go down, and consumption being so close to the source of the energy makes for transmission losses non existent, so instead of having to generate 1.2 KWh to make a customer receive 1.0 KWh, distributed generation would avoid that 0.2 KWh be lost along the way, so there is some technical merits for giving something back to customers that feed electricity to the network, but not necessarily being paid over what a utility "unit" is charged for.

    Just (again) my 2¢.


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


    Just to clarify I said "1kw" not 1 kwh. So a system of 6kw capacity could on a not so sunny but bright day produce 1 kw of power all day. No I cannot run my house on 1kwh - if only!


  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 91,390 Mod ✭✭✭✭ Capt'n Midnight


    Met Eireann 5 day cloud predictions http://www.met.ie/forecasts/5day-atlantic.asp

    other numbers
    http://www.gaisma.com/en/location/dublin.html
    Monthly
    Insolation, kWh/m²/day 0.63 1.31 2.46 3.91 5.12 5.22 5.02 4.28 3.09 1.72 0.79 0.47

    PV is produced during peak daily demand but not during peak annual demand

    So a 100W panel , with optimum sun tracking , would give ~500 Watt hours per day during the summer months ( ~10c of electricity)

    63Wh in January ( one charge of 9 cell laptop battery - get an android tablet or something with a much longer battery life )
    (a bicycle dynamo is 3W and so would give 72Wh over 24 hours)

    The conversion from Insolation to Watts depends on the angle to the sun too, and tracking takes energy and expense (one cheat is to use two opposing DC motors each powered by smaller off axis solar panels)

    Location, location , location
    http://www.metoffice.gov.uk/climate/uk/ni/print.html Armagh - NB lowest sunshine in July was just two hours a day. :eek:
    armagh_sunshine.gif


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


    Today is 12 months since I installed 2.6kw in West Cork. We have done 4kwh today so far but exceptional day as it didn't rain. (mind you there's still time!) Total for the year is 1895 kwh. My target was 2400kwh but the terrible summer blew that away.

    I had a faulty inverter which lost me unknown hours and was changed 3 weeks ago. So that's 5kwh per day average across the year or 729 kwh per kw installed.


  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 91,390 Mod ✭✭✭✭ Capt'n Midnight


    freddyuk wrote: »
    installed 2.6kw in West Cork. We have done 4kwh today so far but exceptional day as it didn't rain. (mind you there's still time!) Total for the year is 1895 kwh.
    That works out at almost exactly the equivalent of 2 hours a day at it's rated power.


  • Registered Users Posts: 36 ✭✭✭ Someone else


    I always smile when folks are working out the pay back in cost, sure most folks are happy to have a car outside their front door depreciating at €4000 P/A...!

    Got hot water system on the roof about 6 years ago for €4000 westerly facing roof :-/ but sure now contemplating spending another €2000 to get them on the Eastern side with a few things added & changed...

    Current plan is PV's on the roof over the next couple of years with a small enough investment to off-set the standby items on all the time, chargers, fridge, PC etc. even 100w x 24 hrs x 365 adds up on you bill so even knocking 20-50% off would be good... so whereas it may not be cost effective to go high level at the moment, it may be at the lower levels & you can always have additions if it works out.

    Also PV systems have come down by 10% per year over the last few years so hopefully in 5 years or so technology may have improved to make it far more cost effective.

    so make initial investment & try & forget about the money... We don't have massive household income but we try & reduce our bills whatever way we can. The house next door, semi-d spend over double on oil then we do. Almost all our hot water catered for equinox to equinox, with some heat the rest of the year.

    energy costs are only going up you know 100% increase in oil over the last 7/8years...


  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 91,390 Mod ✭✭✭✭ Capt'n Midnight


    I always smile when folks are working out the pay back in cost
    ...
    Also PV systems have come down by 10% per year over the last few years
    unless you are going to save 10% this year you may be better off waiting until next year :pac:

    Same thing is true of many renewable technologies BTW. It's an interesting problem. And if you look into current research developments the price is going to keep dropping for years to come.



    However, the cost of cabling and control systems are now becoming a major part of the cost. Also you have to factor in the standing charge and storage costs if you want to go off grid.

    Oddly enough fuel isn't as critical as you may think since less of energy will come from it in future.


    It might be instructive to draw graphs of the predicted changes in prices of these things over the coming years and see what ranges of time the crossover point is.


    Interesting technologies of the future include transparent solar panels that use Ultraviolet or Infra red. It means you can replace windows with solar panels and get electricity from the light that wound' pass through the windows anyway.


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  • Registered Users Posts: 1,627 ✭✭✭ quentingargan


    unless you are going to save 10% this year you may be better off waiting until next year :pac:

    ......It might be instructive to draw graphs of the predicted changes in prices of these things over the coming years and see what ranges of time the crossover point is.


    Interesting technologies of the future include transparent solar panels that use Ultraviolet or Infra red. It means you can replace windows with solar panels and get electricity from the light that wound' pass through the windows anyway.
    Solar PV has probably hit its ultimate low price - at least for now. As of March 1st, those of us importing from China have to register our import with the possibility of having an "anti dumping" tariff of up to 85% imposed retrospectively. So nobody is willing to buy from China and sell at a low margin with the prospect of such a tariff hanging over their heads. This is designed to help European manufacturers (perhaps quite rightly) but will result in a steady price increase.

    Large installed systems in the UK are now costing 92p per watt. The cost of production is coming very close to grid parity, even in this climate. Smaller systems are obviously more expensive, but while it may not be a lucrative proposition, for those wanting to produce their own energy or wanting their household to be a nett exporter of electricity, it won't lose them a fortune either. (not as much as the Beemer parked outside :p

    I do agree that there has been an apocalyptic view of energy future prices which didn't come to pass - I have been on that track myself. But there is a pleasure in having your own energy that is perhaps similar to growing your own vegetables - it may not save you a fortune, but it is satisfying.


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