Solar Panel Guide Discussion

TrickyDicky101

Have you had other quotes? You definitely shouldn't be paying over £10k for this size system (and quite possibly significantly less depending on system).

Lck_2

John_Pierpoint wrote: »

Have you got two inverters, one for each roof?

I don't know - having read a bit more I suspect not. This may sound stupid, but is there an easy way to check?

rogerblack

Lck - if the inverter(s) are installed inside - there will be two similar boxes, not one!

I was surprised looking at the numbers for actually flat mounted panels (or nearly so) that the output isn't really that bad.
Here in Scotland, it gets ~746, not 900kWh/year per kW for optimally sloped panels.
However, it's lots worse in winter - falling to below half output for about 6 weeks extra, with generation in the coldest months falling to almost zero.
Even a minor slope of 10 degrees (a one meter across solar panel sloped at this is under 200mm off the roof at the high point) can boost output by nearly 10% though.

This neglects other major issues.
I'm unsure how the panels would cope with 3 feet of snow on them!
If sloped, the snow at least tends to run off, in periods when it gets a little warmer.

Lck_2

rogerblack wrote: »

Lck - if the inverter(s) are installed inside - there will be two similar boxes, not one!

I was surprised looking at the numbers for actually flat mounted panels (or nearly so) that the output isn't really that bad.
Here in Scotland, it gets ~746, not 900kWh/year per kW for optimally sloped panels.
However, it's lots worse in winter - falling to below half output for about 6 weeks extra, with generation in the coldest months falling to almost zero.
Even a minor slope of 10 degrees (a one meter across solar panel sloped at this is under 200mm off the roof at the high point) can boost output by nearly 10% though.

This neglects other major issues.
I'm unsure how the panels would cope with 3 feet of snow on them!
If sloped, the snow at least tends to run off, in periods when it gets a little warmer.

There is definitely only one big box in the loft

keith_r59

John_Pierpoint wrote: »

How many (say) bicycle manufacturers of 1986, are still offering spare parts, let alone manufacturers of video recorders. Betamax anyone?
How difficult will it be to mix and match a replacement panel?

zeupater

keith_r59 wrote: »

Hi

John isn't trolling, it's a pretty relevant point .... how many manufacturers have the same size panels ?, is there a standard size ?, have manufacturers stopped making certain sizes which they used to ?, did they lay down a stock of spares ?, have any manufacturers stopped manufacturing already ? .... as mentioned, a relevant question to spark a train of thought which therefore deserves consideration.

HTH
Z

Cardew

keith_r59 wrote: »

Talking of trolling - who are 'handful of posters' you accused?

UselessMoney

Have just visited company with a 4.5kw roof install on quite a bright sunny day (for the northwest in october). Latest sanyo panels 250w max very nice (approx £1000ea) BUT when i looked at the generation meter from these panels was seriously dissappointed with the reading averaging a measly 800w (lowest 400w cloud passing to clear bright sun reading of only 1250w). As the amount of power produced will vary from one minute to the next i am at a loss on how to determine precise benefit of the feed in tariff, if anyone can explain (in simple terms) i would be most grateful.

keith_r59

UselessMoney wrote: »

Have just visited company with a 4.5kw roof install on quite a bright sunny day (for the northwest in october). Latest sanyo panels 250w max very nice (approx £1000ea) BUT when i looked at the generation meter from these panels was seriously dissappointed with the reading averaging a measly 800w (lowest 400w cloud passing to clear bright sun reading of only 1250w). As the amount of power produced will vary from one minute to the next i am at a loss on how to determine precise benefit of the feed in tariff, if anyone can explain (in simple terms) i would be most grateful.

You can use one of the many calculators available on the internet. Here are a few for you to try.

http://www.energysavingtrust.org.uk/Generate-your-own-energy/Financial-incentives/Cashback-Calculator

http://www.solarguide.co.uk/solar-pv-calculator

http://www.pvsolarpanelcalculator.co.uk/

Cardew

UselessMoney wrote: »

Have just visited company with a 4.5kw roof install on quite a bright sunny day (for the northwest in october). Latest sanyo panels 250w max very nice (approx £1000ea) BUT when i looked at the generation meter from these panels was seriously dissappointed with the reading averaging a measly 800w (lowest 400w cloud passing to clear bright sun reading of only 1250w). As the amount of power produced will vary from one minute to the next i am at a loss on how to determine precise benefit of the feed in tariff, if anyone can explain (in simple terms) i would be most grateful.

Welcome to the forum.

Are you sure it was 4.5kWp?

The maximum for the highest rate of FIT is 4.0kWp and as the FIT rate drops for all generated power from a system bigger than 4.0kWp, a 4.5kWp system would get less income than a 4.0kWp system. The larger system would cost more to install so it would make little financial sense to exceed 4.0kWp

If the panels cost £1000 each that is £16,000 for a 4kWp and £18,000 for a 4.5kWp system - well above the going rate!

There isn't too much point in taking the instantaneous kW output as the important figure is the annual kWh generated output. For each kWh generated you will get 43.3p and a further 3.1p for 50% of that generated output. Plus you can use any of the generated output in your house.

An estimate for your annual output can be obtained from the links above - and an estimate from an installer should supply such an estimate(get several estimates)

For the North West you should be looking at a figure of around 3,200kWh pa for a 4kWp system on a South facing roof - this will give an income of around £1430 pa.

However that is the simple explanation you requested - read some of the threads for more detail.