Solar Heating - grant aid and advice?

mrmister_3

There are so many firms masquerading as quasi-official organisations in this field. If you read their ‘blurb’ it is full of statements like “savings up to” or “some customers claim savings of ”. As far as I am aware none of these firms will guarantee an output for their systems. Also despite their claims of longevity, the systems are not backed by other than a 2/3 year guarantee. - some are one is offering 5 Years another is giving 10 and 25 years on parts

The problem in getting objective evidence on actual savings from customers is most of them are not prepared to admit in public that they have paid several thousand pounds for a system that just doesn’t deliver. Conjecture.

That said there are hundreds of claims for misrepresentation waiting court appearances and I doubt if there is a Trading Standards Authority in the country that hasn’t issued warnings about the scams going on – do a Google.
If these are incorrectly and inflated priced systems installed then they will likely perform badly but if they are poor systems their data shouldn't be used to taint correctly designed and installed systems that work efficiently. It is unfortunate that rogues will exploit peoples good intentions, and do the industry no good. But data from these shouldn't be used against the industry.

Cardew wrote:

paul_h, who seems quite an expert, inherited a system and calculates that it saves him £60 a year.which would be approx £1050 after 10 years with 10% rises in average energy costs


yakky58 has only fairly recently installed his solar system and in May reported “that Gas consumption is now 30% of what it was for heating water.” It is difficult to extrapolate estimated savings from that statement. Clearly more in the summer and less in the winter. So 50% of the average annual consumption would appear an reasonable assumption - £60-£75pa which would be approx £1200 after 10 years with 10% rises in average energy costs

simonm of Solar Kent has given us the most comprehensive data. (Solar Kent have some connection-an agent??- with Genersys plc who install systems)

His monthly totals of saved energy are recorded and show that his system produced an annual total of 4,434kWh. What is surprising is that 90% of that total was produced and used between April and October – it is difficult to see how most people could use that amount of hot water in that period. Therefore one must deduce that he uses approx double the average amount of DHW.

Even so his savings for the full amount of 4,434kWh would amount to £130pa. which would be £2100 after 10 years with 10% rises in average energy costs

Firstly I have periods when I can spend lots of time here and others when it is impossible, hence my slow replies currently.

I note that while you are fairly quick to counter studies for inaccuracies or ambiguity or simply becasue a solar company installed them you are not so quick to question the validity of savings that are being listed here by persons with solar installed; such areas as how well was the system designed, what type of components how many panels, where are they in the country, angle of the collector quality of the collector, what insulation is employed, design of the solar coil, any number of factors can reduce efficiency and their savings.

Undoubtedly there are many systems installed badly by shady characters for low or extortionate prices. These are likely producing hot water but inefficiently. These are the systems that would likely be giving poor results and a bad name to the industry.

Whilst I am still working on this has anyone seen Mark Brinkleys latest update on solar?

http://www.ovolopublishing.co.uk/housebuildersupdate/2006/04/on-solar-panels.html


And an American point of view
http://www.earthtoys.com/emagazine.php?issue_number=05.04.01&article=apologies

MisterEd

I spent some time reading through these posts; I wonder how many others have stayed the distance. It seems to have dried up recently, probably because the hot topic is now micro wind turbines

My reasoning on solar thermal is as follows:

Energy available from solar radiation in southern England = 1200kWh/m2/year

Claimed efficiency of typical evacuated tubes = 80%

2 square metres of net collector area will therefore give around 2000 kWh of heat energy at the panel. All other losses via pipes and storage tanks would be the same as for any DHW system (assuming insulation standards are the same)

My last heating oil delivery cost about 40pence/ltr. At 10.5kWh/ltr this costs me 3.8 pence/kWh.

My boiler is about 85% efficient so to get 2000kWh at the back of the boiler I need to input 2350kWh worth of oil. So, 2350 x 3.8 = £89 (if on gas using a condensing boiler at 90% efficiency at 2.5p/kWh this would be 2000/0.9x 2.5 =£56)

The 2000kWh at the panel or the boiler exit will not put 2000kWh in the storage cylinder. There will be losses in the pipe-runs and energy used for the pumps in either case - say 20%. This figure could be argued to death but look at:
https://www.silvey.co.uk-costs.pdf
http://164.36.164.20/renewables/publications/pdfs/sp300275-2.pdf

These give a valid idea of losses through a system, and the second one is an excellent test of various types and makes of panels.

So, if 20% is used then we get 1600kWh in the hot water cylinder. To achieve this using electricity from an immersion heater would use 1600kWh at say 10p/kWh = £160 per year

If using economy 7 at 3p/kWh = £48, but you have to pay a higher rate for daytime power used.

A 2m2 system can be installed for about £3000. If I put this on my mortgage if would cost £212 per year.
If I put £3000 in an ISA at 5% interest I earn £150 towards paying my bill.

I used a 2m2 net absorber area evacuated tube for the basis of this. Its important to check the manufactures data for the net area. This is usually recommended as appropriate for two or three persons - depending very much on hot water use, appliances and living style etc. Larger households might justify a larger system. Its important to assess household hot water demand and ways of reducing it, along with more efficient cost-effective ways of heating the water.

Flat plate systems will work OK, but need to be sized upwards. A responsible supplier should take all these factors into account

This roughly coincides with the numbers on the solar trade website in terms of outputs and payback periods. (depending on fuels, locations etc.)

[Deleted User]

As Cardew will know and perhaps a few of the others on this board I have been looking at micro wind turbines with a view to installing at my own home. Well having been very dissapointed by the spurious claims by companies such as WindSave and having received for the 3rd time this year a card from Simplee Solar I thought I would get them in.

The upshot was a visit the other night.

Now I must say I had done a bit of research before hand and expected the worst from them, but thought I would give them a chance first hand.

There was a great dael of insistance from them that my partner should be present during their presentation (on the grounds that they really want to spread the solar thermal message) but I think it was more on the grounds that if they could persuade me to buy they would need joint signatures from both my partner and I (we own the house in joint names).

So the presentation began with a gentle discussion on our house and why we are interested - in my part mainly for financial reasons and secondly for the future of my children.

Then some discussion on the fact that I had looked at micro turbines (which got condemed by Simplee man as being next to no use because they would fail from a mechanical point of view and need constanct maintenance).

Then onto the main even of how much we could save. Well I only have oil for all my heating be it hot water or CH (there was a nice bit of soft selling and undermining the competition at this point by saying that they would never claim that there system could do the CH, like a lot of other companies do) but that there system could achieve 70% of our total hot water requirments and that our hot water (not including CH) probably accounted for 60% of our domestic use of Oil.

Anyway i reckon my Oil use for hot water heating and CH probably works out at around £1000 per year (going up all the time with rising Oil prices, its trippled in the last 6 years), so the statement was made that his system could save me 50% on my Oil bill.

All sounds good so far but then came the crunch. How much for the system

wait for it



go on the tension is killing you.



Yes that's right a very reasonable


£9,000!!!!!!

Only £9,000 I hear you say a bargain and if I signed there and then he could probably reduce it to c. £6,000 ("or something like that" because of marketing and having a board outside and etc etc etc.

Anyway still not a problem, although no way am I going to sign on the night.

My issue is he tried to persuade me that with a cost of £9,000 (he appeared to forget about the potential of £6,000 ish) and a payback fo 18 years before I even broke even that I was onto a winner.

Of course he said that Oil prices would continue to rise (which I agree long term they will) and wouldn't it be terrible if we ran out of Oil in the next couple of years, what would I do then. (Freeze to death in my house is the answer without central heating during the winter, which he has already told me his system cannot do), anyway after the scare tactics I told him that I accept oil prices will rise, but my £9,000 invested in a tax free savings bond in my wifes name will pretty much generate £400 a year in interest (never mind the compound on it over 18 years) and that as oil prices rise so are interest rates likely to rise and so will the return on my savings, which will help offset my rising oil prices.

Anyway you get the gist of the counter arguement. Still there was a lot of suggestion that the system would pay for itself in only 10-12 years, to which I say, why dont I wait until oil has got so dear that when I spend a sensible amount of money on a system with a reputable firm (and prices are bound to fall as mass production makes the product cheaper and mass purchasing enables them to reduce the "retail" price of the product) that it will actually have a payback of just a 3-5 years which I can live with.

By the way did you know that Simplee Solar are, quote " installing 120 of these systems a week" !!!!!!, but that if I wanted to visit a happy and satisfied customer of theirs that they couldn't help me by pointing me in that direction because of the data protection act (lol) and if perhaps I suggested that they could speak to one of their satisfied customers and get them to call me instead, they said "what's the point of that, we are hardly likely to get a disatisfied customer to call you" but it would be nice to speak to somebody who is actually happy.

Cardew

MisterEd wrote:

This roughly coincides with the numbers on the solar trade website in terms of outputs and payback periods. (depending on fuels, locations etc.)

MisterEd,
Excellent post - albeit I fear it may be a little too technical for some who believe that Solar will save them huge sums.

I would comment that the cost of oil has now reduced considerably(20-25%) from the 40p/ltr you quote; although that price could just as easily move in either direction - as indeed could gas and electricity.

Apart from that I think all your figures are as accurate an estimate as possible; although there is a valid argument to say many older domestic boilers do not have as high an efficiency as those you quote.

The definition of payback period is interesting.

The bottom line is you have suggested a system cost of £3,000. This will cost you £212pa if added to your mortgage, £150pa loss of interest in an ISA,

Your savings on the 1,600kWh you calculate as £89pa for oil, £56pa for gas, and £48pa for Economy 7 electric. I think you must discount anyone who heats all their water on a daytime tariff(and presumably heats their house the same way.)
Those savings are roughly what most informed sources quote for solar DHW. e.g. £50-£75pa.

So in my book to spend £150pa to £212pa to save £48pa to £89pa means you never achieve a payback; you simply go deeper into debt.

For any other purpose, if someone suggested you should spend £150pa to £212pa to save £48pa to £89pa you would think them slightly odd - no seriously odd!!
Can you imagine someone saying I can fit a device to your car that will achieve those savings above and will cost you as above?

P.S.
Usual disclaimer - I am looking at this purely from a Money-Saving perspective, I accept that some are prepared to spend such sums for 'Green' purposes.

Cardew

Freddix,
I have had some flyers from Simplee Solar and have thought of doing exactly as you have done; although I doubt I would have kept my temper!

I would have insisted that he put something in writing about projected savings. To claim 50% savings off an oil bill is an absolute disgrace. 10% would be too high.
With Oil, Gas or E7 electricity with a well designed solar system £50-£75 is as much savings as anyone will make.

[Deleted User]

So having turned down Simplee's wonderful offer of a Solar Thermal system for £9,000, they called me back last night to say that they haven't managed to convert anybody in my local area and rather than waste money readvertising.......

They could offer me a better deal. Turns out I could now have the system for £4,600. Well how amazing is that?

Not very is the answer, they clearly think I'm going to be impressed with a 50% reduction. Well if they started at £4,600 to begin with and came down to £3,000 I might have been interested, but the fact that they wanted to rip me off with £9,000 to start with hasn't made me very happy.

What I'm really suprised with is that if the do 120 of these a week (how come they are so desperate to just give it away now!!).

Freddix

MisterEd

Cardrew
I checked with my local oil supplier, and as you suggested, the price has fallen since last year and is now 31 pence per litre or 30pence per kWh. (down from 40 pence and 38.5pence respectively) This would reduce the potentiial savings from a 2m2 evacuated tube system to £70 per year (down from £89)

I know my earlier posting started off a bit technical but I felt it was time to toss a few things that we know we know into the discussion. As I'm sure you know, the solar radiation data and the capabilities of the panels are well researched and documented, and are where all the other estimated percentages start from. Its when honest attempts are made to estimate savings for "typical households" based on this data, that things start to go wrong. Some unscrupulous or misguided salespersons tend to cherry-pick bits of information and misuse them to suggest inflated or even outrageous potential savings - such as the "50% of total oil consumption" or the "£340 per year saving on an oil bill" mentioned in earlier postings.


Freddix
I tried to look-up the simplee solar website to check their technical details but the site is "under repair", so I can't see what they are offering you. If you have the info, look and see what the net area of the collector is and if its evacuated tube or flat-plate. The figures I mentioned here and in my earlier posting will apply to you just as they do to me or anyone else (assuming you live in the UK), but will be slightly worse the further north you are. Try to ignore the percentages they promise look at the possible outputs available from the panels.

As you appear to be a fairly high energy user - £1000 per year in oil - they may have suggested a larger system than the 2m2 evacuated tubes I based my numbers on. If so, then simply bump the saving up accordingly eg.
3m2 saves £105
4m2 saves £140

If they are offering flat-plate panels, then as a rough guide you should add about a square metre of net area to get similar results.

Even if simplee come back and offer you a system for £3000, is it such a great money saving deal? I suggest not. Where I live, one company advertises that it will install a 2m2 system for £3000 but the return of £70 per year simplee just does not justify it.

Whether you want to save money or the planet there are probably more cost effective ways of achieving both in terms of your energy bills or CO2 emmissions. Sadly they are all a bit dull compared to solar panels or wind turbines. Insulation, heating controls, new boiler, low energy lightbulbs etc etc.

On BBC's newsnight a few days ago, their so-called "ethical man" had an energy audit on his home. One possible improvement identified was was to replace his 6 radiator valves with thermostatic radiator valves (trv)s, which would save him an estimated £48 per year. His plumber quoted £300 to do the job and ethical man replied that he wouldn't bother at that price.

£300 seemed a bit steep to me for valves that cost £6 or £7 each, but better value than solar panels costing 10 to 30 times as much for little more return.

Cardew

MisterEd wrote:

Cardrew

Freddix
I tried to look-up the simplee solar website to check their technical details but the site is "under repair", so I can't see what they are offering you.

Mister Ed,
Are you aware that Simplee Solar were the subject of a TV programme. See:

http://forums.moneysavingexpert.com/showthread.html?t=254075&highlight=Simplee

MisterEd

Freddex
There are lots of sad tales re. simplee on this thread. Looks like you had a lucky escape.

http://forums.moneysavingexpert.com/showthread.html?t=69974&highlight=solar+panels

Cardrew
I didn't see that TV programme but saw a later one on Solar Technik operating in the south-west. I once had a salesman from Spectrum Energy (now defunct) visit me just to hear what lines they use to sell these over-priced setups.

I read the Guardian article that appears in the thread and agree with your comments - its poor and misleading. There seems to be several threads running on this solar panel topic at present.

callansdad

Hiya,

i have a quick question to throw into the discussion. I'm not looking for a huge long winded technical answer (as informative as they are) and i dont mean that in a derogatory manner.

we are replacing our roof and i am acutely aware of a product called a solar slate which can be used in place of a real slate. Does anyone have any experience of these? Would they be worth CONSIDERING in place of real slates (more cost effective than just lumping solar panels on your roof)?

I do know that they are considerably more expensive than real slates.
We are replacing roof anyway, any thoughts?