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Solar PV generation
 Started by  pjcomp
 27 Sep 2009, 5:01 PM

I've just started looking into the possibilities of solar PV panels - we've got a south-facing roof which should be a good place to site them. Anyone had any experience of them, good, bad, indifferent, they can share? All information useful ....
Excellent simple technology. Make sure your system is correctly sized for your needs and you can expect to get in the region of 70% of your annual hot water needs from it. There are arguments in favour of evacuated tube and flat plate type collectors so worth doing some research to help you decide. Do you have a solar cylinder yet?
What most impressed me about the installation was that the next day the sun came up and it all worked perfectly. And while I wasn't surprised it worked on sunny days it also works on days without bright sunshine. All quite amazing and worth every penny.
EDIT Sorry pjcomp...I have realised since writing this post that you asked about PV not solar thermal...apologies and next time I need to take time to read the OP more carefully!

Do you have natural gas for your heating?
If so Micrto CHP will be cheaper, about 7,000 and produce about 1,100 - 1,300 kWH p.a. compared to a 2kW peak solar PV system at 11,000. Unfortunately the yield is just 110 - 130p.a
They run on either Natural Gas or LPG.
Of course there is a small cost of running the gas, but the economics speak for themwelves.

Where are they going to get microCHP from Niall?
PVs are brill by the way. You get what you pay for in this life.
We've started assembling quotes on a 2KW system with a view to installation soon. Two suggestions: shop around and talk to possible suppliers about exactly what they're suggesting and why. We've found two or three people we're very happy to work with, and the same number who we've decided we aren't going with. And the articles by Jerry Clark in Green Building Magazine (Spring and Autumn 09) give a knowledgeable user's view, and a year's history.
Baxi do Micro CHP, it will be available generally from january 2010
What's Micro CHP?
A small combined heat and power plant.
Possible example -- a small diesel generator making electricity and using the heat (usually wasted) for heating or hot water production their efficiency is quite high.
CHP still uses diesel, so compared to solar pv it's not as clean nor as reliable. Solar pv has 25yr guarantee and no moving parts, it is also self cleaning and the paybacks are far better over the 25yr period. I would go pv any day out of all renewables available.Boogie
Just to clear up a common misunderstanding:
The term " SOLAR PV " doesn't exist within the trade, only amateurs refer to it. The correct term is "PV" for photovoltaic.
PV elemets/panels need no sunshine to produce electric energy, a lamp does the trick as well. Or indirect sunlight,like the moon and from further away:
the stars. Or candels.
On clear nights larger PV installations produce electricity as well, small quantities admitted but measureable, sellable.
The guarantee chrisheathcote refers to is only on the cells/panels functionality, not on the harvest of the combined installation.
Get the entire installation's output guaranteed by a manufacturer.
The installer might promise anything and will be never seen again.....

Hot Stuff:
The German coffeshop chain TCHIBO is selling now PV installations as well. Tchibo is operating in the UK as well, so keep an eye on their special offers.
Here the German link:
Hi PV gives a good return on your investment PV panels are very durable most panels come with a 25 year warranty it is basically a plug and play system. A domestic system can be installed 1-3kW in a couple of days. A south facing roof is ideal but shading issues need to be considered such as trees or roof abutments.
On 1st February 2010 The Government confirmed the feed in tariffs which will come into force on 1st April 2010.
Feeded-in tariffs are new measures introduced by the government to support the uptake of Microgeneration technologies in the UK.
For someone fitting a typical2.5kW photovoltaic solar system to an existing home, a payment of 41.3p per KWh generated will be paid whether that electricity is exported or used by the home owner. A further payment of 3p per kWh will be made for each unit not used and therefore exported to thegrid. New-build properties fitted with solar panels will receive a lowertariff of 36.1p per kWh generated.
These tariff payments are guaranteed for 25 years and they are also indexlinked - i.e. they will rise in line with inflation. The typical 2.5kWsystem will generate tax-free payments of around 1000 per year, and so the payback on the investment will be around 12 years. This also work out as a tax-free return on investement of 8% - far better than any bank account offers, and particularly attractive to those paying tax at the higher rate. Since the electricity generated can be used by the homeowners,
Hope this helps
The "payback" period can only be defined when you input a system cost against the systems rated performance. You should be aiming at a payback period of around 8 years on most systems below 4 Kw.
The feed in tariff rate drops to 36p per Kw when the system is over 4KW
Can anyone recommend a PV panel that delivers the best energy and how much they cost for a roof project. I appreciate I also need an installation cost as well but am trying to keep costs down
Unless the instllation is done by - or at least signed off by - someone with the Microgeneration Certification Scheme certificate you won't be able to get the feed-in tariff, which scuppers the payback for the scheme. If you go looking for a panel, choose a German or Japanese one, avoid the Chinese kit as it usually isn't up to snuff.
As well as the panels you need the DC cabling, inverter, the right set-up of isolation switching, and a conenction into your consumer unit, which in itsself comes under Part P of the Building Regs, so again needs to be done by or signed off by someone sutably certified.
They all get them China whatever it says on the tin!!!
And Chinese ones are just as good or better if count cheaper as worth having.
Re Chinese modules - remember that to get the feed-in tariff the equipment must be MCS certificated as well as the installer. There are lots of Chinese ones on the MCS list with the usual 20 year output guarantees.
I have access to 1kW kits, MCS accreditted, to include panels, inverter, generation meter, cables, fixing kits etc. In fact all you need to install.
They come with a 25 year manufacturer's warranty on the panels.
Price 3,800 + VAT + delivery
what's the area of your 1kW kits, NiallMac?
1kW system is 7.2 square metres, but you would need to add a small, 50mm margin around the installation.
Interesting to read some earlier comments regarding Micro CHP plants. Here in Sweden, every city, town and largish village have them. Fuel varies from forest waste, chipped, industry waste, and household rubbish. All our household rubbish is now incinerated, as in Denmark and Norway. Incineration at CHP plants has been done here since the late 50s, and today they are extremely efficient, running at very high temperatures, NO dixoines are released and emissions are about 37 lbs/Mwh. More than 50% of homes and industries here get their hot water and heating from these plants, most efficient and cheap
I just contacted biggest solar panel manufacturer in India with vew to import for my new build, although it may not be suitable to use because of shading from the trees. But photovoltic as I beleive may be used in partial shed?
Am I wrong?
If I get any answer, the cost ect, I will post it here

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