Solar panels

conlof

Hey guys. Like the rest of you I got a pamplet regarding solar panels this morning. I am awaiting a call back from the company. What i really want is a total installation cost so I can work out how much I can save and whether it is worth it. this will all come down to money but I reckon that with fuel prices going the way they are I will have to do it sooner rather than later. Has anyone looked in to this? planning permission, management company, grants, CBA etc
I will post the results of my phone call when i have them.

pixbyjohn

There are 2 different systems. One is tubes and the other is a panel type system. They are used to heat the domestic water in your cylinder for the bath/shower and the kitchen hot tap. They do NOT heat the radiators.
The tube system cost approx 4000 euro whereas the panel type costs approx 8000 to 12000 euro. (Cost depends on how many panels are required to gather the rays required. The grant in both cases is 800euro I am almost sure.
You can have the panel sitting over your roof tiles or sunken into the roof. Or you can have it raised and supported with brackets. Hope this helps

homer911

http://www.boards.ie/vbulletin/forumdisplay.php?f=1041

Lots of advice on the Renewable Energy Forum

I'm not in Greystones, but I used a guy in Bray to do mine - get a few quotes if you can

pixbyjohn

Solar panels are made from silicon and transfer’s the sun’s radiation into usable
renewable energy in the form of electricity. Solar panels produce a clean renewable form of electricity with no CO2 emissions into the environment.


The energy absorbed from the solar panels travels through a pump, from there passes through a fill and relief valve. The energy then changes forms when it reaches a heat exchanger where it can be stored or used in the form of electricity and space/ water heating.


A configuration of passive thermo siphon is used to connect a number of panels together to maximize solar absorption.

A backup electric and gas water heater is included incase not enough energy has been collected from one of the solar panels. This type of configuration ensures that maximum solar energy is being collected from the rest of the solar panels to offset the defected one.

There are two types of solar panels or solar cells suitable for domestic use.
Flat Panel Arrays and Evacuated tubes, (more than one) are available in different heights and widths.
Most are about 1m2.

Evacuated tubes work on the same principle as the flat panel solar cells, but due to their design are far more
efficient at collecting solar energy. Evacuated tubes have been around for years and are extensively used in Canada,
Germany, China and England. Evacuated tubes use a twin glass tube made of borosilicate glass which makes them extremely durable.

This type of design allows maximum absorption with minimal reflection. The top of the tubes are fused together and all air within the tubes is pumped out at the same time the tubes are exposed to extremely high temperatures.
This "evacuation" of the gasses forms a vacuum, which is an important factor in the performance of the evacuated tubes.


Due to the vacuum process the tubes are extremely efficient at collecting heat from solar energy.
A vacuum is excellent at insulation which is why the tubes were designed as such.
The vacuum prevents any heat loss from the tubes due to the highly efficient insulation properties.
The inside tube could be as hot as 150C while the outer tube is cold to the touch.

Due to this design evacuated tubes out perform the flat panel models and collect maximum solar
energy even in bad weather.

FirstIn

Wear an extra jumper. Or perhaps tights under your trousers. Much cheaper.

Re washing, join a gym and wash there. You could also enjoy the benefits of extra exercise.

Re solar power I did hear something like the following;
Even increasing the temp by a few degrees with the panels (e.g on dull days) will prove a significant benefit as bringing the temp up from that point to a suitable washing temp will not take much more energy.

I think it works like this, water at lower temps needs a lot of energy to move up a few degrees, but at slightly higher temps the amount of energy needed reduces. Thus if the solar panels get you a few degrees hotter water to start with then the gas/electricty energy needed will be small.

I stand to be corrected on that, however I assure you an extra jumper is benefical for keeping warm :-)

The Bishop Basher

Can't recommend them enough. We have the tubes, west facing, cost about €5000 all in but we have free scalding water 6 months of the year and it's luke warm the rest so cheaper then heating from cold. As Jon says though, they won't heat the rads. . Haven't worked it out but with energy prices rising all the time it can't take too long before your recoup your initial outlay and start to hit the black.

homer911

The payback time is generally viewed as 8-10 years, but can vary a lot

If you are looking purely to save money, the best investment you can make is to improve your loft insulation (assuming you already have d/glazing and dry-lined, and have draught-proofed your home)

caesarthechimp

pixbyjohn wrote: »

Solar panels are made from silicon ....

Good info, but to clarify on the names; "Solar Panels" can be Solar Thermal (hot water) or Solar PV (photo voltaic- electricity)
Within Solar thermal, there is flat panel and also evacuated tube.

pixbyjohn

Enrate wrote: »

Good info, but to clarify on the names; "Solar Panels" can be Solar Thermal (hot water) or Solar PV (photo voltaic- electricity)
Within Solar thermal, there is flat panel and also evacuated tube.

Yes. Both systems are over priced, and in this country will have a shorter life than usually stated. Then they become a liability on your roof.

Linho

Hi, we've had someone do a survey and just wondering if anyone knows approximately how it works in terms of cylinder size. 6 in our house and it's been recommended that we get a 350litre cylinder. The entire cost coming in at about 7,000 net of grant. Does that sound right/reasonable...it's our 1st quote but seems a bit higher than what I'm reading elsewhere????
Thanks

millie81

Linho wrote: »

Hi, we've had someone do a survey and just wondering if anyone knows approximately how it works in terms of cylinder size. 6 in our house and it's been recommended that we get a 350litre cylinder. The entire cost coming in at about 7,000 net of grant. Does that sound right/reasonable...it's our 1st quote but seems a bit higher than what I'm reading elsewhere????
Thanks

Hi there,
Ive got a system in and it didnt cost anywhere near that (€4,600) so I would really suggest that you shop around...

richiek67

Hi Folks,

Just wondering if anyone else has had this quite annoying quandary?
I'm all into the whole Green energy thing and I work in Electronics and also know quite a bit about house construction and plumbing. I do all the DIY etc and I',m quite handy! Ok, thats the first bit.
The first time I mentioned solar to my wife she diden't like the idea at all. I had a feeling that this would happen ok so I had decided to just work on it slowly to eventually get her round to my way of thinking. We had friends in the country who built a new house and installed the Tube type on the roof etc. Ok, she was fine with that idea due to the fact that it was a new house etc and was done at the stage of building....Same thing with other friends in swords!
Anyway, we are in Celbridge, not many with it there...I've seen one or 2..

To continue ( sorry if this is boring... )

Her attitude I though was beginning to change I thought ( by the way, money was not the issue here because I had put some away for this ).
Anyway, we live in a house thats 30 years old approx and we've had a do a lot to get it into the condition its in now. A lot of the workmanship has a lot to be desired I have to say but its a fairly big house and generally ok.
Her fear of late seems to be all the plumbing etc and just the whole upsset, although I have assured her that in the 2 day installation all will be fine. The panel simply sits on the roof with one pipe coming through a small hole....even this was an issue...cant think why.
I was getting more frustrated at my lack of understanding her somewhat illogical ideas that this was a whole lot more complicated than it actually was.
I had been in talking with AEI ( alternative energy ireland ) which had given me a quote of 4k5 after the grant etc but included the high spec Kingspan tubes ( which i gather are top notch patent pending etc). This had been going on for about 8 months.
The other day I told my wife that I was talking to them etc and i'd wait until the holiday time of around June to sort it although the guy was pushing for march as things apparently start to get busy at this stage onward for solar!!
Anyway, she nearly threw a wobbler, said she owned half the house too and was entitled etc bla bla and in the end of the day dident want to have it done due to the fact that the house was too old and things might go wrong....we ended up having a huge fight over the whole thing and I tried to explain to her that it was being fitted by trained guys who knew what they were doing.
When I also explained that the price of Oil in continuing to sore, she dident care!! ( infact the money saved by installing this I think is a lot grater than any money sitting in an account, which is what this is doing, and earning no bloody interest at all)
So , I told her I'd forget the whole thing if she paid for the oil!!!!


Anybody have any similar happenings with their partners or what.? I have to say that I was really pissed off ( still am )and insulted to a degree given my knowledge and , what I feel, is her lack of technical understanding and trust on my part too
Can anyone suggest anything, ......:(:(:(
I'm actually really disappointed that I cannot do this....

homer911

richiek67 wrote: »

Hi Folks,

Just wondering if anyone else has had this quite annoying quandary?
I'm all into the whole Green energy thing and I work in Electronics and also know quite a bit about house construction and plumbing. I do all the DIY etc and I',m quite handy! Ok, thats the first bit.
The first time I mentioned solar to my wife she diden't like the idea at all. I had a feeling that this would happen ok so I had decided to just work on it slowly to eventually get her round to my way of thinking. We had friends in the country who built a new house and installed the Tube type on the roof etc. Ok, she was fine with that idea due to the fact that it was a new house etc and was done at the stage of building....Same thing with other friends in swords!
Anyway, we are in Celbridge, not many with it there...I've seen one or 2..

To continue ( sorry if this is boring... )

Her attitude I though was beginning to change I thought ( by the way, money was not the issue here because I had put some away for this ).
Anyway, we live in a house thats 30 years old approx and we've had a do a lot to get it into the condition its in now. A lot of the workmanship has a lot to be desired I have to say but its a fairly big house and generally ok.
Her fear of late seems to be all the plumbing etc and just the whole upsset, although I have assured her that in the 2 day installation all will be fine. The panel simply sits on the roof with one pipe coming through a small hole....even this was an issue...cant think why.
I was getting more frustrated at my lack of understanding her somewhat illogical ideas that this was a whole lot more complicated than it actually was.
I had been in talking with AEI ( alternative energy ireland ) which had given me a quote of 4k5 after the grant etc but included the high spec Kingspan tubes ( which i gather are top notch patent pending etc). This had been going on for about 8 months.
The other day I told my wife that I was talking to them etc and i'd wait until the holiday time of around June to sort it although the guy was pushing for march as things apparently start to get busy at this stage onward for solar!!
Anyway, she nearly threw a wobbler, said she owned half the house too and was entitled etc bla bla and in the end of the day dident want to have it done due to the fact that the house was too old and things might go wrong....we ended up having a huge fight over the whole thing and I tried to explain to her that it was being fitted by trained guys who knew what they were doing.
When I also explained that the price of Oil in continuing to sore, she dident care!! ( infact the money saved by installing this I think is a lot grater than any money sitting in an account, which is what this is doing, and earning no bloody interest at all)
So , I told her I'd forget the whole thing if she paid for the oil!!!!


Anybody have any similar happenings with their partners or what.? I have to say that I was really pissed off ( still am )and insulted to a degree given my knowledge and , what I feel, is her lack of technical understanding and trust on my part too
Can anyone suggest anything, ......:(:(:(
I'm actually really disappointed that I cannot do this....

It sounds like your problem is nothing to do with Solar, more your wife getting upset at the thought of more mess - I know my wife cant understand that you cant improve something without making some sort of mess in the process.

Can you get her to talk to a neighbour who has had a system installed? The access to "free" hot water when the work is done and the elimination of arguments over how long the immersion has been on are well worth it!

homer911

I got a guy in Bray to my panels - happy to pass on his details by PM if anyone wants. He is married to a Bray Town Council member..

recedite

richiek67 wrote: »

I had been in talking with AEI ( alternative energy ireland ) which had given me a quote of 4k5 after the grant etc but included the high spec Kingspan tubes ( which i gather are top notch patent pending etc). This had been going on for about 8 months.

The worst that can happen is you only save about €350 a year and the panels fall apart after 15 years. In that case, you break even. But as the Kingspan panels are Irish made and the installers are presumably Irish taxpayers at least you have spent your money here, instead of sending it off to the Middle East.
On the other hand, if the price of oil rises, and the panels last for 30 years, you stand to save a lot of money.

ConorOB

Hiya,

I've got to answer these questions as there's a lot of misinformation and confusion here. Just to let ye know, I'm a solar installer myself, and have specialised in this line of work for the last 8 years with over 400 installations completed.
-Planning permission is not needed for houses unless your property is a listed building.
-Management companies rarely allow modifications to the outside of apartments.
-Grants are still available, capped at €800
-To correctly size a system, a cylinder is chosen based on the water usage, eg 200 litres for 3-4 people, 300 litres for 5-6 people. The solar collector is sized based on the orientation of the roof and priced based on it's quality, warranty and aesthetics. Budget solutions for 3-4 people should cost 3.5k after grant, 5-6 people costing 4.5k after grant.
-Like most products, the more you spend, the higher quality you'll get including longer warranties.
-Tubes will sit proud of the roof and minimise labour and cost. Panels are chosen when aesthetics are a consideration and are built into the roof, having removed tile or slate. These end up looking like velux windows, demand more labour and so cost more, however do NOT cost anything near 8k-12k if your being quoted by a reputable company.
-There's no point getting panels and raising them on support brackets. If your collector's going to sit proud of the roof then get tubes. They're more effective.
-Installation can be finished in 1 day however may take up to 2 days. There is a very minimum of disruption to any household while the job is happening, (The hot water will be off for 3-4 hours and the attic off limits for the day).
-The maths are simple. With solar hot water heating you're highly unlikely to need any other water heating source from March-late October. During winter the solar will preheat your domestic hot water and so will reduce your oil/gas costs by up to 20%. This happens very simply because the closed circuit of central heated water returns to your heater, with less heat extracted from it because your domestic hot water is typically 25-35 degrees with solar as opposed to 5-10 degrees without it. As your heater is thermostatically controlled, it ignites your burner less frequently to maintain the desired house temperatures.
Many of my previous customer have calculated that they will recover their costs in 6-8 years and that doesn't calculate the increase in BER their properties have gained.

My advice to anyone considering solar is to get at least 3 quotes from solar specialists, not plumbers who've done a few jobs recently because their plumbing work has slackened.
Just because someone has the right qualifications on paper doesn't mean they have the experience to do the job right so make sure to get at least 2 references in your area who will vouch for the company's expertise and professionalism. Visit them if you can to verify they've actually got a system in place.
The only people that say solar doesn't work in Ireland either have no first hand experience of it or have a system that wasn't installed properly.
The only people that say solar isn't worth it either didn't shop around for a competitive quote or have a system that wasn't installed properly.
In short, solar works very effectively and economically in Ireland IF it's installed by someone who knows what they're doing. Make sure you choose a specialist.
Feel free to PM me or ask any other questions.

richiek67

Women....Mentioned it to her again last night , just in passing, she wanted to do something, I mentioned ' o well, if I can do my solar I'll agree' . Well, She just said, 'o your not on about that F***ing thing again. Can tell you this, I think shes being totally unreasonable and I'm not going to facilitate her any more in the DIY cause I've just lost interest in the house and having to bother.
:eek::mad:

richiek67

I wish you could talk to my wife. She mentioned planning permission, I said dont need any. She said ' how do you know. I know! She still doesn't believe me ( FME )

If you can explain to me why women will not go ahead with this kind of thing I'd be grateful. Or even ask some women you know.

Cheers

Rich

ConorOB wrote: »

Hiya,

I've got to answer these questions as there's a lot of misinformation and confusion here. Just to let ye know, I'm a solar installer myself, and have specialised in this line of work for the last 8 years with over 400 installations completed.
-Planning permission is not needed for houses unless your property is a listed building.
-Management companies rarely allow modifications to the outside of apartments.
-Grants are still available, capped at €800
-To correctly size a system, a cylinder is chosen based on the water usage, eg 200 litres for 3-4 people, 300 litres for 5-6 people. The solar collector is sized based on the orientation of the roof and priced based on it's quality, warranty and aesthetics. Budget solutions for 3-4 people should cost 3.5k after grant, 5-6 people costing 4.5k after grant.
-Like most products, the more you spend, the higher quality you'll get including longer warranties.
-Tubes will sit proud of the roof and minimise labour and cost. Panels are chosen when aesthetics are a consideration and are built into the roof, having removed tile or slate. These end up looking like velux windows, demand more labour and so cost more, however do NOT cost anything near 8k-12k if your being quoted by a reputable company.
-There's no point getting panels and raising them on support brackets. If your collector's going to sit proud of the roof then get tubes. They're more effective.
-Installation can be finished in 1 day however may take up to 2 days. There is a very minimum of disruption to any household while the job is happening, (The hot water will be off for 3-4 hours and the attic off limits for the day).
-The maths are simple. With solar hot water heating you're highly unlikely to need any other water heating source from March-late October. During winter the solar will preheat your domestic hot water and so will reduce your oil/gas costs by up to 20%. This happens very simply because the closed circuit of central heated water returns to your heater, with less heat extracted from it because your domestic hot water is typically 25-35 degrees with solar as opposed to 5-10 degrees without it. As your heater is thermostatically controlled, it ignites your burner less frequently to maintain the desired house temperatures.
Many of my previous customer have calculated that they will recover their costs in 6-8 years and that doesn't calculate the increase in BER their properties have gained.

My advice to anyone considering solar is to get at least 3 quotes from solar specialists, not plumbers who've done a few jobs recently because their plumbing work has slackened.
Just because someone has the right qualifications on paper doesn't mean they have the experience to do the job right so make sure to get at least 2 references in your area who will vouch for the company's expertise and professionalism. Visit them if you can to verify they've actually got a system in place.
The only people that say solar doesn't work in Ireland either have no first hand experience of it or have a system that wasn't installed properly.
The only people that say solar isn't worth it either didn't shop around for a competitive quote or have a system that wasn't installed properly.
In short, solar works very effectively and economically in Ireland IF it's installed by someone who knows what they're doing. Make sure you choose a specialist.
Feel free to PM me or ask any other questions.

The Bishop Basher

Well it's only February and with the last few warm days we already have a tank full of scalding hot water with no need for immersion or boiler.

As for the wife, if it was me i'd just go ahead and do it but can't really help you there i'm afraid.

ConorOB

Most women are reluctant to lose hot press space, as the cylinder is considerably bigger than standard cylinders, however we point out that there will always be an abundance of hot water, for relaxing bubble baths every single day without the guilt of immersion or heating costs, even AFTER the kids have had showers! Most women regard a long hot bath as an all too infrequent luxury. Those with solar hot water heating have them every day, with no waiting for water to reheat and no expense.
If you would like references of people in your area, please PM me.
BTW, there is absolutely no mess made in any house. References will testify to that.

Also, re: Planning;
Q. Do I need planning permission to put solar panels on my roof?
A. Solar installations which conform to the exemptions listed in Statutory Instrument 83 (SI No 83) do not need planning exemptions. Otherwise you will need to contact your local agency / planning authority, and they will advise you as to whether or not you will require planning permission for a solar installation in your particular area.
( from http://www.seai.ie/Renewables/Solar_Energy/FAQs/#Planning? which is a government agency)

pixbyjohn

ConorOB wrote: »

Hiya,

I've got to answer these questions as there's a lot of misinformation and confusion here. Just to let ye know, I'm a solar installer myself, and have specialised in this line of work for the last 8 years with over 400 installations completed.
-Planning permission is not needed for houses unless your property is a listed building.
-Management companies rarely allow modifications to the outside of apartments.
-Grants are still available, capped at €800
-To correctly size a system, a cylinder is chosen based on the water usage, eg 200 litres for 3-4 people, 300 litres for 5-6 people. The solar collector is sized based on the orientation of the roof and priced based on it's quality, warranty and aesthetics. Budget solutions for 3-4 people should cost 3.5k after grant, 5-6 people costing 4.5k after grant.
-Like most products, the more you spend, the higher quality you'll get including longer warranties.
-Tubes will sit proud of the roof and minimise labour and cost. Panels are chosen when aesthetics are a consideration and are built into the roof, having removed tile or slate. These end up looking like velux windows, demand more labour and so cost more, however do NOT cost anything near 8k-12k if your being quoted by a reputable company.
-There's no point getting panels and raising them on support brackets. If your collector's going to sit proud of the roof then get tubes. They're more effective.
-Installation can be finished in 1 day however may take up to 2 days. There is a very minimum of disruption to any household while the job is happening, (The hot water will be off for 3-4 hours and the attic off limits for the day).
-The maths are simple. With solar hot water heating you're highly unlikely to need any other water heating source from March-late October. During winter the solar will preheat your domestic hot water and so will reduce your oil/gas costs by up to 20%. This happens very simply because the closed circuit of central heated water returns to your heater, with less heat extracted from it because your domestic hot water is typically 25-35 degrees with solar as opposed to 5-10 degrees without it. As your heater is thermostatically controlled, it ignites your burner less frequently to maintain the desired house temperatures.
Many of my previous customer have calculated that they will recover their costs in 6-8 years and that doesn't calculate the increase in BER their properties have gained.

My advice to anyone considering solar is to get at least 3 quotes from solar specialists, not plumbers who've done a few jobs recently because their plumbing work has slackened.
Just because someone has the right qualifications on paper doesn't mean they have the experience to do the job right so make sure to get at least 2 references in your area who will vouch for the company's expertise and professionalism. Visit them if you can to verify they've actually got a system in place.
The only people that say solar doesn't work in Ireland either have no first hand experience of it or have a system that wasn't installed properly.
The only people that say solar isn't worth it either didn't shop around for a competitive quote or have a system that wasn't installed properly.
In short, solar works very effectively and economically in Ireland IF it's installed by someone who knows what they're doing. Make sure you choose a specialist.
Feel free to PM me or ask any other questions.

Have you fitted a solar system/s in the Greystones area yet ?
Do you have any sites where you have installed that can be viewed ?
Thank you for your info

bamboozle

we're based in Dublin and had solar panels fitted 3 years ago. original cost was about €3,500 grant at the time came in around 1600 IIRC,

i've little or no interest in payback period, we had just bought the house and were renovating it and adding an extension so it was perfect time to add on solar.

what i love about the solar:
provides all hot water from late March to late Sept/early Oct (unless the very odd time i've been dull for a few days and someone's had a bath)
winter time it heats the water to about 15-20 degrees.
adds value to the house if we ever considered selling on.
adds to the energy rating of the house
gas/oil prices are only going one way, we're reducing our dependancy on them

fclauson

Swanner wrote: »

Can't recommend them enough. We have the tubes, west facing, cost about €5000 ....

I have just picked this one out of all of the posts

I do not want to stop people spending to save the planet - or spending becuase "they think its the right thing to do" - but

do you know how much you spend per year on hot water ?

Lets say its 3500 Kwh (thats for a family of 6)
and lets say you price/kw is 12c (depends on your system efficency and if its oil or gas or HP but check out the SEAI site for fuel per Kw )

and then lets say inflation for your fuel is 12% (thats agressive)

and lets say that your solar panels provide 60% of you hot water (thats optomistic)

how much would you save over 15 years - ??

Answer about €1200

Now assume I am 50% out - thats €2400

So is investing 4K for 2.4K return over 15 years (and this takes no account of the electricity used to run the pumps etc)

Is that a good investment - or should you have spent 4K making you house more airtight ?

Your thoughts are welcome ??

The Bishop Basher

I haven't worked out the figures and to be honest I couldn't be arsed.

A bit like when I buy a car, I don't work out the cost/mpg/cost to change etc. I just buy a car I like and enjoy driving it. Life should be fun ya know.

I fitted them because we were building a house and €5000 wasn't a lot in the scheme of things to future proof it against energy price increases.

That said, we also spent a lot of extra money ensuring it was well insulated.

All I know is we don't use an immersion or a boiler for 6 months of the year. We have all our hot water needs supplied by the sun and for the remaining 6 months we spend far less heating an already warm tank.

All of the above = vastly reduced energy bills - Now.

The 5k is spent. I don't think about it. Could have spent it on the kitchen. I still wouldn't think about it. All I know is I pay substantially less now and will continue to do so for the next 20 years.

After that, who knows.

fclauson

Swanner wrote: »

... and €5000 wasn't a lot in the scheme of things ....

- thats over 1% of my budget - might not sound a lot - but .......

The Bishop Basher

fclauson wrote: »

- thats over 1% of my budget - might not sound a lot - but .......

Fair enough. Can I assume your building then ?

Based on your figures, we were working off roughly half your budget and still haven't looked back. I suppose I saw it as investment in future energy and i'm glad i did. At a time when energy prices are soaring, I have the next 6 months of "free" hot water to look forward to.

Also, far easier to do it on a new build then later on although retro fitting may be cheaper when you include the grants.

daheff

fclauson wrote: »

how much would you save over 15 years - ??

Answer about €1200

Now assume I am 50% out - thats €2400


Your thoughts are welcome ??

if you were 50% out it'd be 1800...not 2400. 2400 is twice 1200 (100%+ 100%)



richiek67 -ur missus doesnt want it. get over it. shes a right to an opinion to.

MicktheMan

fclauson wrote: »

Answer about €1200



Your thoughts are welcome ??

I just did rough sums and it looks like the 1200 saving is in year 15 alone!
I make the total saving over the 15 years at roughly 9400!

(This assumes that the fuel inflation of 12% is annual and not total inflation over the 15 years)

bamboozle

fclauson wrote: »

I have just picked this one out of all of the posts

I do not want to stop people spending to save the planet - or spending becuase "they think its the right thing to do" - but

do you know how much you spend per year on hot water ?

Lets say its 3500 Kwh (thats for a family of 6)
and lets say you price/kw is 12c (depends on your system efficency and if its oil or gas or HP but check out the SEAI site for fuel per Kw )

and then lets say inflation for your fuel is 12% (thats agressive)

and lets say that your solar panels provide 60% of you hot water (thats optomistic)

how much would you save over 15 years - ??

Answer about €1200

Now assume I am 50% out - thats €2400

So is investing 4K for 2.4K return over 15 years (and this takes no account of the electricity used to run the pumps etc)

Is that a good investment - or should you have spent 4K making you house more airtight ?

Your thoughts are welcome ??

dont ignore the value that is being added to the house & the opportunity cost of each years annual savings...for argument sake the annual saving could go be spent on extra insulation, electricity monitors, boiler service, long life lightbulbs etc. Plus the grant received should also be knocked off the cost of the panels.

saibhne

fclauson wrote: »

I have just picked this one out of all of the posts

I do not want to stop people spending to save the planet - or spending becuase "they think its the right thing to do" - but

do you know how much you spend per year on hot water ?

Lets say its 3500 Kwh (thats for a family of 6)
and lets say you price/kw is 12c (depends on your system efficency and if its oil or gas or HP but check out the SEAI site for fuel per Kw )

and then lets say inflation for your fuel is 12% (thats agressive)

and lets say that your solar panels provide 60% of you hot water (thats optomistic)

how much would you save over 15 years - ??

Answer about €1200

Now assume I am 50% out - thats €2400

So is investing 4K for 2.4K return over 15 years (and this takes no account of the electricity used to run the pumps etc)

Is that a good investment - or should you have spent 4K making you house more airtight ?

Your thoughts are welcome ??

Just a few questions on this:
Why would you take 15 years as the period to determine your ROI? Solar systems can operate for 30 years or so..

Also if a house is well insulated like swanners is then why not invest your money in something that has a good return?

And a few comments.

I think a 60% solar fraction is entirely possible - depends on whether the system you install is designed to give you that.

It's worth noting that 12c per kWh is assuming the water is being heated with gas/oil really. If the water is heated with electricty your cost per kWh is more like 15c per kWh inc VAT and rising.

The value of having a clean and Irish source of fuel in our energy mix is also not quantified here. In terms of energy security this is advantageous as it is in terms of climate change mitigation. As a country we buy 90% of our energy needs from other countries - we are very exposed in this regard and we need to change this to be more competitive as an economy. Solar thermal can be a small contribution to this and is an easy one to make happen.

fclauson

daheff wrote: »

if you were 50% out it'd be 1800...not 2400. 2400 is twice 1200 (100%+ 100%)

So you are spending €1800 per year in year one for your hot water - you need to look at that - a well controlled h/w system for a family of 6 should be costs a lot less than that (and remember we are only talking about hot water and only the saving in heating hot water in the summer)

MicktheMan wrote: »

I just did rough sums and it looks like the 1200 saving is in year 15 alone!
I make the total saving over the 15 years at roughly 9400!

(This assumes that the fuel inflation of 12% is annual and not total inflation over the 15 years)

Can you share the maths - please

saibhne wrote: »

Just a few questions on this:
Why would you take 15 years as the period to determine your ROI? Solar systems can operate for 30 years or so..

please don't kid your self - after 15 years tubes, pumps, and anti freeze fluid will all need replacing/repairing - not a total replacement but a majour refurb - and by then the hyrdogen fuel cell will be available and the refurb will not be necessary

Also if a house is well insulated like swanners is then why not invest your money in something that has a good return?

And a few comments.

I think a 60% solar fraction is entirely possible - depends on whether the system you install is designed to give you that.

but the capital costs will be higher - there is a diminishing return after about 50% - more sqM per Kw delivered

It's worth noting that 12c per kWh is assuming the water is being heated with gas/oil really. If the water is heated with electricty your cost per kWh is more like 15c per kWh inc VAT and rising.

unless its a HP then its about 4c to 6c
but
I agree - it does depend - and may be if you are just using an immersion for your h/w then spending 4K may help with this might make sense (although you should look at other heat sources if you are refurbing your h/w & heating system

The value of having a clean and Irish source of fuel in our energy mix is also not quantified here. In terms of energy security this is advantageous as it is in terms of climate change mitigation. As a country we buy 90% of our energy needs from other countries - we are very exposed in this regard and we need to change this to be more competitive as an economy. Solar thermal can be a small contribution to this and is an easy one to make happen.

Never disputed that just looking at a purely financial return

fclauson

also look at the attached

BryanF

fclauson wrote: »

please don't kid your self - after 15 years tubes, pumps, and anti freeze fluid will all need replacing/repairing - not a total replacement but a majour refurb

Francis how will the lifespan of your preferred HP compare with the SP?
what sort of guarantees and assurances have you gotten?
what's the efficiency and potential maintenance comparison over their lifespans?
Is it relevant that your SP/fossil v HP comparison is based on a passive house standard distribution?

goat2

i hope to get the tubes, but what is really off putting is the price, too much, i will look to go down the diy route, putting a tank in attic which will be warmed up by the panels, and feeding my hotpress tank off this, that way i will have less to buy, just ordinary inderect tank and change connections around a bit

MicktheMan

fclauson wrote: »

Can you share the maths - please

kWh price increasing at 12% per annum, 60% of annual dhw from solar

Year ----kWh ----Price/kWh ----Annual dhw cost ----60% saving
1

---

3500 ----0.12

---

420

---

252
2

---

3500 ----0.13

---

470

---

282
3

---

3500 ----0.15

---

527

---

316
4

---

3500 ----0.17

---

590

---

354
5

---

3500 ----0.19

---

661

---

397
. . . . .
. . . . .
. . . . .
14

---

3500 ----0.52

---

1833

---

1100
15

---

3500 ----0.59

---

2053

---

1232

---

Total saving over 15 years 9394

Note that general inflation has not being taken into account!

fclauson

Mick - you are right - I made a BIG mistake in my maths

but (tries to recover);)

fuel prices today assuming oil we should use about 0.085 at say 90%
http://www.seai.ie/Publications/Statistics_Publications/Fuel_Cost_Comparison/Domestic_Fuel_Costs_Comparison_January_2012_pdf.pdf
which changes things a bit = €7437 costs after 15 year

If your system cost €4.5K then thats €2937 saved

All I was trying to point out is that there are not the BIG immediate savings with solar to be made which people thing
with a pay back of 11,12,13,14 years depending - its a long term investment

fclauson

BryanF wrote: »

Francis how will the lifespan of your preferred HP compare with the SP?
what sort of guarantees and assurances have you gotten?
what's the efficiency and potential maintenance comparison over their lifespans?
Is it relevant that your SP/fossil v HP comparison is based on a passive house standard distribution?

Brian - basically I don't know - my parents fridge is 20 years old - I had one which failed after 5 - (both use the basic same compressor technology that a HP does)

MicktheMan

fclauson wrote: »

All I was trying to point out is that there are not the BIG immediate savings with solar to be made which people thing
with a pay back of 11,12,13,14 years depending - its a long term investment

I agree ... most people don't have the first clue what it costs them to heat their water or even what is the most efficient method.

recedite

fclauson wrote: »

Lets say its 3500 Kwh (thats for a family of 6) ....

Also, 5000 - 6000 Kwh (units of electricity) is more realistic for a family of 5 people.
So, 5500*€0.12*0.6*15 years = €5940 even with no fuel inflation.

Better to pump a few grand into our own green economy, than to be permanently importing dirty fossil fuels from abroad. And if you can save money while you're at it, everyones a winner.

BryanF

fclauson wrote: »

Brian - basically I don't know - my parents fridge is 20 years old - I had one which failed after 5 - (both use the basic same compressor technology that a HP does)

fclauson wrote: »

also look at the attached

FC, can we see a little more detail on the brake down of the costs here thanks

fclauson

recedite wrote: »

Also, 5000 - 6000 Kwh (units of electricity) is more realistic for a family of 5 people.
So, 5500*€0.12*0.6*15 years = €5940 even with no fuel inflation.

Better to pump a few grand into our own green economy, than to be permanently importing dirty fossil fuels from abroad. And if you can save money while you're at it, everyones a winner.

6000kWh for just heating the hot water per annum ?

fclauson

BryanF wrote: »

FC, can we see a little more detail on the brake down of the costs here thanks

Sure

the usage numbers are taken from a combination of DEAP and PHPP - both have their own view on how much energy demand my build will have.

Using those as a base number I then calculated the costs for each system over 15 years (which was selected for no good reason other than than oil & gas boilers have a life of about that)
Assumes equal capital outlay (which is a bit skewed because at the low energy demand end of the scale a HP is cheaper to install than SP + Thermal store + Oil or Gas)
Also remember that as part of this I have to hit part L renewables - because obviosuly the very cheapest from a capital costs perspective would be a cheap and chearful oil boiler on its own.

given these energy demands then I calculated running costs

Attached is the spread sheet - just change the YELLOW boxes to enter you own deamand figures

Please do me a favour and publish your results here - so we can do a bit of a public compare

Do-more

recedite wrote: »

Also, 5000 - 6000 Kwh (units of electricity) is more realistic for a family of 5 people.

I made an attempt to quantify energy usage for our DHW a few months ago.

All our DHW is heated by electric immersion. I should have fitted an energy monitor on it last year to get an accurate figure but could only do a guesstimate from our electricity bill.

Working backwards so that any errors or inaccuracies add to the DHW portion of the bill I figured that for our family of 4 worst case is currently 3000kWhr per year for DHW.

I was surprised at that myself expecting it to be higher, granted the kids are only 5 & 8 so are not teenagers standing in the shower for 30mins a time!

MicktheMan

recedite wrote: »

Also, 5000 - 6000 Kwh (units of electricity) is more realistic for a family of 5 people.

Our dhw is only heated by our non-condensing ch oil boiler (have never used the immersion) and we use between 300 and 320 liters of oil per year to heat the dhw.
This would tally pretty well with FC's figure for dhw use. There are 5 in our household including 3 teenage girls!
So the 5-6000 kwh figure is deffo on the high side.

Merch

fclauson wrote: »

Sure

the usage numbers are taken from a combination of DEAP and PHPP - both have their own view on how much energy demand my build will have.

Using those as a base number I then calculated the costs for each system over 15 years (which was selected for no good reason other than than oil & gas boilers have a life of about that)
Assumes equal capital outlay (which is a bit skewed because at the low energy demand end of the scale a HP is cheaper to install than SP + Thermal store + Oil or Gas)
Also remember that as part of this I have to hit part L renewables - because obviosuly the very cheapest from a capital costs perspective would be a cheap and chearful oil boiler on its own.

given these energy demands then I calculated running costs

Attached is the spread sheet - just change the YELLOW boxes to enter you own deamand figures

Please do me a favour and publish your results here - so we can do a bit of a public compare

Equal capital outlay for HP to Sp based on a new instal maybe?? I cant imagine the capital outlay for a HP, space heating system to be cheaper than any other existing system given the kind of work needed to be done.
Is the efficiency for the HP given an average across a year as it surely will go up and down through the year? and be different for space and dhw? what is the COP for dhw using HP, thought HP was better for space heating than dhw and better performance on the basis it was run quite continuously at low temp and not on and off, thereby offsetting the gains? unless it is in a 24hour occupied building.
HP still uses electricity, only, whereas SP offsets the amount of gas/oil used to heat water reducing the consumption. HP only maintains the advantage if the COP can be guaranteed to be between certain values all the time surely?
Out of curiosity, in the event of a power/pump failure, what fail safe prevents damage to solar thermal (tubes) if the pump doesnt run for the above reasons?

recedite

MicktheMan wrote: »

Our dhw is only heated by our non-condensing ch oil boiler (have never used the immersion) and we use between 300 and 320 liters of oil per year to heat the dhw.

How do you know how much oil went on space heating, and how much on DHW only?

MicktheMan

recedite wrote: »

How do you know how much oil went on space heating, and how much on DHW only?

I have 2 hour meters, 1 connected to the space heating pump and the other to the dhw pump. Each hour meter is activated when its pump and burner are energised. I then convert the hours recorded into liters of oil consumed by the boiler jet size / oil pressure. It is quite accurate as oil consumed matches what gets delivered:)

fclauson

Merch wrote: »

Equal capital outlay for HP to Sp based on a new instal maybe?? I cant imagine the capital outlay for a HP, space heating system to be cheaper than any other existing system given the kind of work needed to be done.

My maths is comming from the point of a new build

Is the efficiency for the HP given an average across a year as it surely will go up and down through the year?

yes - COP is a measurement at a point in time SPF is an average - averages are averages and no manufactuer publishes them

and be different for space and dhw? what is the COP for dhw using HP, thought HP was better for space heating than dhw and better performance on the basis it was run quite continuously at low temp and not on and off, thereby offsetting the gains?

there is much debate as to what the COP of h/w is - DEAP uses a number of calcs - but 0.75 of heating COP is consider roughly ok

HP still uses electricity, only, whereas SP offsets the amount of gas/oil used to heat water reducing the consumption. HP only maintains the advantage if the COP can be guaranteed to be between certain values all the time surely?

yes - but one can run with averages to get a close approximation

Out of curiosity, in the event of a power/pump failure, what fail safe prevents damage to solar thermal (tubes) if the pump doesnt run for the above reasons?

each manufacturer handles this differently - but it has to be handeld some how

fclauson

MicktheMan wrote: »

I have 2 hour meters, 1 connected to the space heating pump and the other to the dhw pump. Each hour meter is activated when its pump and burner are energised. I then convert the hours recorded into liters of oil consumed by the boiler jet size / oil pressure. It is quite accurate as oil consumed matches what gets delivered:)

Cool - I think all building should do this - it would get rid of the nonsense of guessing

Merch

fclauson wrote: »

each manufacturer handles this differently - but it has to be handeld some how

Do you have an idea how it is handled? I was thinking of some battery backup, solar or charged from mains running a seperate pump via a bypass, but I havent seen how it is managed.
As I am in an existing build I definitely would consider solar evacuated tubes as my best option.

On a seperate note, is it possible to try and determine your own BER, I googled DEAP but cant find the download for it on the seai website, is it easy to input any data or does it require some practice or specific knowledge?

fclauson

DEAP

check out
http://www.seai.ie/Your_Building/BER/BER_Assessors/Technical/DEAP/