Free solar panel discussion

Been reading some Solar Threads on MSE with interest. Although not all 128 pages on here!

We just moved into a new home and hopefully will be long term. It has a mainly south to southwest facing garden. I guess its a bit of a lottery if you get accepted though.

I wont ask if it is worthwhile actually getting the panels at all as I will have to make my mind up from advice on here and dont want to dig up that argument!

But I do have some other questions if anyone would oblidge, would be most grateful.

1. If I was offered free ones or could pay for the installation up front. What would be the most financially worthwhile option? (We are coming into a bit of money). Should I hurry too, as I heard FIT prices will drop next year?

2. My father in law is a builder, uncle and electrician and have various other trades in family. Can you get on the FIT scheme with
a cheaper installation? Or does it need to be by a certified company like ASG or a shader greener who can charge up to 10x what it would cost me to get it fitted? (sorry read that somewhere too so might be an exaggeration). Could I install and rather like retrospective planning get it certified afterwards for FIT?

3. If I did a DIY install can I sell the electricity back to the national grid? (even if I cant get on the FIT scheme)

4. If 2. comes up as im forced to go for an "official company" is it better to install a smaller £2k DIY panel system for hot water, than outlay £12k on a full system and hope break even in 10 years?

5. I already have half of my loft converted to a small room with 2 velux windows. There is also a chimney in the middle. I haven't done the measurements but the roof is a reasonable rectangular size. How much space do I need? 23 square feet I read in one thread? Is that true? Would they fit them "around" the obstables mentioned if there is room or is it too much hassle?

Oh and can anyone recommend a DIY panel kit?

Sorry (if this has been answered before I will read back through the 100 pages or so tonight) and that is also way more questions that I planned to ask!

I've worked with 5 companies going through MCS all have spent between 6 - 8k going through MCS and 6 months of hard slog - if that makes DIY more economical for you then that's the route for you to go down. Just don't foget the annual ongoing fees and inspections costing between 3 - 5k. It's often too much for a smaller firm to cover, not so bad for a larger company with more jobs to spread the cost over.

Be careful not to confuse solar thermal (hot water) with pv (electric) costs and benefits are completely different. You can't have pv anywhere near shade because it stops the panels or cuts down production by a huge amount on any of the panels that are strung together. You also need loads more space for pv than you do for thermal - sounds like you might be more suited to solar thermal if you have limited roof space.

HTH

Hi edd1178

Welcome to the forum .....

I agree with your analysis ..... it's really a matter of balance, but when you have a system, no matter how hard you try, you will be pushed to believe that a significant number of people would save much more than £100/year and this seems to be a figure which is indepentant of system size or whether they are 'rent-a-roof' or owned installations ..... unless there is a significant baseload, bigger arrays just export a higher proportion of what is generated.

HTH
Z

ed1178 wrote: »

Thanks Zeupater, although I do feel I have to disagree. My interest in this technology was sparked recently when I went to see a potential new home which had recently been fitted with a user funded system. Although the estate agent wasn't sure of the size of the array, she was able to show me paperwork showing an avarage of £100 a month return. This does not sound alltogether unreasonable based on the following quick calculations (Please forgive inaccuracies in FIT prices etc, I have only just started to investigate it all!

£100 a month from FIT = 285 kwh at 35p (guess!)
285kwh / month = 9.5kwh / day

Surely 9.5 kwh / day is not beyond a decent sized system, operating over daylight hours it equates to less than 1kw an hour. I know a system will probably average 30% of its maximum output during daylight hours, but still a 3kw system should deliver this.

As to how much a 3kw system will cost I have no idea, but I guess I am one of the lucky ones - someone else has paid for this technology but I will reap the benefil if I buy the house!

On a lighter note - I did have to laugh when I was shown the kitchen complete with oil burning 4 oven AGA - The vendors green credentials and bank balance would both be considerably higher had he saved his solar money and instead bought a conventional cooker!

Hi

The point raised was related to the value of electricity saved and excluded the FiT payments and export value for owned systems.

The power generated has to be decoupled from the power used. For example, if a household consumed an average of XkWh of electricity per day with an array sized at YkWp, simply doubling the size of the array wouldn't double the consumption, so the consumption and generation are not directly linked ..... both 'rent-a-roof' operators and installers (who quote self consumption savings based on an assumed 50% of total generation being the in-house consumption without regard to actual customer usage) tend to ignore this as it simply makes their offerings less attractive.

On a 3kWp system you would likely have FiT/assumed export payments of around £1100 (depending on location, orientation etc) and then add the self consumption energy saving of around £100 which equates to the £1200 figure you mention, which again would seem to confirm £100 as being the likely saving which a 'rent-a-roof' installation would expect.

Good luck with the house hunting ....

HTH
Z

ed1178 wrote: »

£100 a month from FIT = 285 kwh at 35p (guess!)
285kwh / month = 9.5kwh / day

Surely 9.5 kwh / day is not beyond a decent sized system, operating over daylight hours it equates to less than 1kw an hour. I know a system will probably average 30% of its maximum output during daylight hours, but still a 3kw system should deliver this.

As to how much a 3kw system will cost I have no idea, but I guess I am one of the lucky ones - someone else has paid for this technology but I will reap the benefil if I buy the house!

!

As said above, this particular thread is for 'free' solar PV systems (known as 'Rent a Roof')where the company who installed them get all the FIT and export payments. The house owner merely gets any of the solar generated electricity he can use in the house.(for agreeing that a company can use his roof for 25 years)

A 3 kWp system will probably cost arount £10k now - it might have been £3k more a year or so ago.

One would normally expect a 3kWp system to generate on average around 2,600kWh a year - so your 285kWh per month(3,420kWh pa) is too high. On the other hand FIT is now 43p/kWh and you get a further 3p/kWh for 50% of generated power.

The issue here is how much of the generated electricity can be used in the house. There is plenty of evidence from people who have had panels for some while that they will use between 500kWh and 1,000kWh a year - so up to £100.

Even one of the best companies(A Shade Greener) who participated in another thread did not dispute a figure of £100 a year - and WHICH give similar estimates.

Indeed if anyone has gas CH and starts using an immersion heater, to use up the generated electricity, they could lose money.

The problem is that some people having got Rent a Roof systems make silly over-estimates of how much they will save - probably they need to convince themselves the gains are higher than they will actually achieve. See the other thread that is currently running.

The problem is that these over-estimates cannot be challenged in that thread and so will give a totally false impression of likely savings.