Free solar panel discussion

dali1972

Hi All

ive read all of the posts and have a few minors issues.

1. im pxxxed off that only registered companies can install the panels to enable you to get the £800 per yr (if you pay for the install yourself)
2. if you let someone have your roof space...they get the money.

So unless we can build our own and also get the £800 per year... it makes no sence to do it yourself.

Ive been told that my wallet is super glued to the pocket it stays in... ive looked at building the panels myself...your thoughts on the below are welcome.

If your house is OK/garden for free standing frames, then the cost of £12k /£800 per yr is roughly 15 yrs. maybe less if you have more panels, more sun. But case scenario is maybe 10yrs before payback. Then money comes in if its still about!!!! (even if its supposed to be guarenteed for 25 yrs... do i belive that ...cough..NO)

All of the above is about payback times, and as many have said... i want this because its eco friendly blah blah. I would only do anything if it makes sence and either costs me nothing in a very short time or breaks even fairly quickly.

People have forgotten/not mentioned that solar power can actually be stored.... in what are called deep cell batteries... but they are not cheap. So would we be allowed to store any excess...no i cant imagine so...as the installers get 3p per unit if we dont use it!!!

So... has anyone concidered forgetting the tarrif's and concentrated on what the costs are on making these simple panels.

I have... Solar "cells" (not the panels) can be imported from China...the main place they are made for pennies a cell (if bought in quantity).
It takes a soldering Iron, a glass sheet, sealing agent, cells, some angle iron for the frame to make the panel. Plenty of posts on youtube

here is a fairly easy one to follow
search youtube for "How to make a solar panel at home part 1"

Most of the bits can be bought on ebay very easily. So i priced up making 10kws of panels at a price of about £850 in total. A few pounds for the framing to mount the panels on the roof...and time of course.

So in truth the total cost would be about £1500/1800 including the batteries to store the power, you can of course also buy and grid tie invertor to sell excess power back to the grid(after an inspection). BUT...making them yourself will not entitle you to the FiTs payment (someones getting back handers out of this im sure of it!!!)

So if the cost saving of electric would be £180/200 per yr, then that works out to be 10 yrs.... so it doesnt look good to make them your self now, and im angry only approved companies can put them up for you to get the grants.... its either about being green... or allowing a nice company to reap the rewards after a few years as im sure they would also be able to make them for a few hundred a pop aswell...or pay out vast sums... mmmm lots of thinking to be done here me thinks.

otherwise...start a big group to buy in bulk from china and drive the price down ourselves...another thought.

digitaltoast

albyota wrote: »

come on, digitaltoast, get with the programme, A 2 kWp array generates electricity and pumps it into the national grid, you carry on using your appliances as normal, but the feed in tariff from the energy co's pay you for generating 2 kWp/yr, so a 2kWp system in the midlands would pay you about £700 per year, would this not wipe out your leccy bill?....even with your 2.5 kW AC on, incidentally a 2.5kW air con system would only use around 900 watts to create that duty.

So, from...
http://www.solarserver.com/knowledge/lexicon/k/kwp.html

the mean output over the period of a year is only about one thenth of the peak output due to night-time and less than optimal day-time sun conditions). The peak output is so based on measurements under optimal conditions, and, specifically, the peak output (some Manufacturers also designate this as the nominal or rated value: rated power, rated output, nominal power, nominal output) results from the product of the nominal voltage and the nominal current.

So, the system that people are signing up for would give them 576 watts peak, then divide that by ten. An average of half an incandescent lightbulb.

But hey, sign up by all means. Let us know how you get on, won't you?

Mcfi5dhc

digitaltoast wrote: »

So let me get this right - you've got a conservatory that heats up your house so you need to put on the AC? Riiight...

OK, well, aircon is about 2.5kWh.
The average power delivered by south-facing 20%-efficient (and that's quite high) photovoltaic panels in Britain would be 20%× 110 W/m2 = 22 W/m2.

A kilowatt is 1000 watts, so you'd need 45 square metres per kilowatt, or 112.5 square metres to run aircon (or kettle or water heater).

This scheme gives you 24 square metres. Good luck with powering anything more than your tv and amp...

What a load of rubbish!

A 3kwp system (like the one on the scheme) will generate roughly 3 kwh per hour, more than enough to run the air con. Clearly, aircon will be used when its sunny, which is coincidentally when the panels are generating.

I have a 1.44 kwp system. When I had a spinning meter, it was going backwards most of the time in sunny weather despite me boiling kettles or using the washing machine.

Sharp NU180watt panels measure 1.31 square metres for a 180 watt version (including the frame). You'd need 6 of these to get 1 kwp (it would actually give you 1080watt peak) and they would take up 7.86 metres

http://www.sharp.co.uk/cps/rde/xchg/gb/hs.xsl/-/html/product-details.htm?product=NU180E1&cat=46000

Those dimensions are just for the panels I have, other comapnies will differ, but be similar.

Now, if you wanted to run aircon 24/7, then maybe you would need 100 metres of panels, but that isn't what the previous guy said.

You really shouldn't post on a subject you clearly know nothing about

Rocky67_2

We're just going through the process and so far it has been really easy. Our only problem is being available when the guy wants to come and see us to fill in the paperwork - it's too far for him to travel on an evening/weekends etc unless he's got other clients to see on the same day. This makes me think it's too much trouble for them. We've got a fitting date of 1st Sept so will let you know how we get on.

digitaltoast

Mcfi5dhc wrote: »

What a load of rubbish!

A 3kwp system (like the one on the scheme) will generate roughly 3 kwh per hour, more than enough to run the air con. Clearly, aircon will be used when its sunny, which is coincidentally when the panels are generating.

I have a 1.44 kwp system. When I had a spinning meter, it was going backwards most of the time in sunny weather despite me boiling kettles or using the washing machine.

Sharp NU180watt panels measure 1.31 square metres for a 180 watt version (including the frame). You'd need 6 of these to get 1 kwp (it would actually give you 1080watt peak) and they would take up 7.86 metres

http://www.sharp.co.uk/cps/rde/xchg/gb/hs.xsl/-/html/product-details.htm?product=NU180E1&cat=46000

Those dimensions are just for the panels I have, other comapnies will differ, but be similar.

Now, if you wanted to run aircon 24/7, then maybe you would need 100 metres of panels, but that isn't what the previous guy said.

You really shouldn't post on a subject you clearly know nothing about

So where's my maths failing me then?
I've just looked up 10 domestic electric kettles. NONE are less than 2.2kWh. Your system is 1.44 kwp, that's a theoretical ideal-world equatorial maximum.

If your meter is spinning backwards when you're using more than you're producing, then you've discovered the holy grail of energy. You should get on the phone to the Rutherford Appleton Laboratory.

How about this:
http://lowcarbonkid.blogspot.com/2010/03/does-pv-solar-electricity-work-in-uk.html

Solar panel manufacturers quote figures for the “peak power” and “installed capacity” of their products. According to industry standards these are the amounts of electrical output in watts that they would generate if one kilowatt per square metre of the sun’s energy were to fall on them. But how close is this to the amount of sunshine at your location? These figures can be found out from the same source on insolation given in the section on solar water heating. For most of the latitudes that cover England and Wales, the summer insolation is a fraction of that figure. Even Europe’s sunniest place, Limassol in Cyprus, only gets 325 W per square metre. London gets 198 and Edinburgh 172 in July. In December, the figures are 96, 22 and 13 respectively. So in the winter, it’s a lot less -- and that’s when you need more power because the lights will be on for longer.

And here's Monbiot: http://www.guardian.co.uk/commentisfree/2010/mar/01/solar-panel-feed-in-tariff

The government is about to shift £8.6bn from the poor to the middle classes. It expects a loss on this scheme of £8.2bn, or 95%. Yet the media is silent. The opposition urges only that the scam should be expanded.

On 1 April the government introduces its feed-in tariffs. These oblige electricity companies to pay people for the power they produce at home. The money will come from their customers in the form of higher bills. It would make sense, if we didn't know that the technologies the scheme will reward are comically inefficient.

The German government made the same mistake 10 years ago. By 2006 its generous feed-in tariffs had stimulated 230,000 solar roofs, at a cost of €1.2bn. Their total contribution to the country's electricity supply was 0.4%. Their total contribution to carbon savings, as a paper in the journal Energy Policy points out, is zero.

A week ago the German government decided to reduce sharply the tariff it pays for solar PV, on the grounds that it is a waste of money. Just as the Germans have begun to abandon their monumental mistake, we are about to repeat it.

Now, what were you saying about a load of rubbish?

Jon_Tiffany

digitaltoast wrote: »

So, from...
http://www.solarserver.com/knowledge/lexicon/k/kwp.html


So, the system that people are signing up for would give them 576 watts peak, then divide that by ten. An average of half an incandescent lightbulb.

But hey, sign up by all means. Let us know how you get on, won't you?

This is so wrong, you really shouldn't be posting such misleading and obviously inncorrect information. A 3kWp system will give, 3kW peak output, enough to run 30 100w incandescent bulbs, or around 300 energy saving bulbs. Over a year the system will produce around 2,500kWh

chucknorris

Anyone reading this please note that this is just a starting point and seriously needs refining with better info, so don't value the scheme on this crude early calulation.

I have just completed 2 spreadsheets one a savings account depositing £12,000 over 35 years and the other calculating the benefits of the panels over 35 years. I have assumed:

£800/year tax free rising in line with the RPI of 3% (an assumption had to be made over a long period)
Fuel savings of £120/year also rising with inflation
Minimal maint for the panels (so small it doesn't really effect the comparison)
Savings rate of 6% (I know rates are low at the moment but I am assuming normal times ahead, an asumption has to be made)
Assumed after 35 years the panels need replacing and have no value (is this reasonable????)

For a 40% tax payer it takes over 24 years to outperform the savings account
For a 20% taxpayer it is still way behind the savings account after 35 years.

If anyone has better info I can feed this into the spreadsheet, I don't see this as the final analysis, merely the starting point before changes are made.

Have I understood the benefits correctly ie that you would receive approx £800 + save £120 on bills or is there more to benefit by selling electricity? This would be crucial to the calculation. I only noticed this scheme 30 mins ago, so it's quite possible I have missed something.

Mcfi5dhc

digitaltoast wrote: »

So where's my maths failing me then?
I've just looked up 10 domestic electric kettles. NONE are less than 2.2kWh. Your system is 1.44 kwp, that's a theoretical ideal-world equatorial maximum.

If your meter is spinning backwards when you're using more than you're producing, then you've discovered the holy grail of energy. You should get on the phone to the Rutherford Appleton Laboratory.
Now, what were you saying about a load of rubbish?

Domestic kettle - 2.2 kwh - correct
Time taken to boil said kettle - about a minute
Units used, about 0.05kwh

Now then, if you wanted to boil a kettle continuously for an hour, a 2.2kwp system would be fine and dandy, but my 1.44kwp system wouldn't be able to cope.

My meter DID spin backwards when I generated more than I was using. This was frequent when the washing machine was on, kettle boiling, TV on, playstation on, simply because they don't take the full load continuously.

If I was generating 1.44kwh, and using 2kwh for example, then my meter would spin the correct way

I repeat, you were talking a load of rubbish, and you shouldn't be posting misleading information. Jon Tiff is correct as well as me.

Mcfi5dhc

chucknorris wrote: »

I have just completed 2 spreadsheets one a savings account depositing £12,000 over 35 years and the other calculating the benefits of the panels over 35 years. I have assumed:

£800/year tax free rising in line with the RPI of 3% (an assumption had to be made over a long period)
Fuel savings of £120/year also rising with inflation
Minimal maint for the panels (so small it doesn't really effect the comparison)
Savings rate of 6% (I know rates are low at the moment but I am assuming normal times ahead, an asumption has to be made)
Assumed after 35 years the panels need replacing and have no value (is this reasonable????)

For a 40% tax payer it takes over 24 years to outperform the savings account
For a 20% taxpayer it is still way behind the savings account after 35 years.

If anyone has better info I can feed this into the spreadsheet, I don't see this as the final analysis, merely the starting point before changes are made.

Have I understood the benefits correctly ie that you would receive approx £800 + save £120 on bills or is there more to benefit by selling electricity? This would be crucial to the calculation. I only noticed this scheme 30 mins ago, so it's quite possible I have missed something.

What size system are you calculating against? A 2.2kwp system will generate about 2000 units a year, giving you roughly £800 a year back off the FIT, but a 2.2kwp should be less than £12,000.

chucknorris

Mcfi5dhc wrote: »

What size system are you calculating against? A 2.2kwp system will generate about 2000 units a year, giving you roughly £800 a year back off the FIT, but a 2.2kwp should be less than £12,000.

Thanks, I have only just become aware of this scheme (hours ago) hence my request for more info from someone that knows a lot more about it. What cost would you suggest for a 2.2kwp system? Have I misunderstood something about this scheme as there seems to be conflicting info in Martin's details about it:

Alternatively, if you shell out £10k for your own system, it's predicted you can earn £1,000s profit from a govt. scheme that pays for all the energy you produce

The other bonus is that a new government scheme pays c. £800/year for all the solar energy you produce

Yet, if you’ve a spare £12,000 and want to keep the panels for more than 10 years, you may be better off paying for your own system


I imagine that the conflict is only due to the range of systems available and what they provide.