Solar energy and feed in tariff

cts_casemod

Cardew wrote: »

I assumed he meant 2 to 4 kWh but agree it is not clear.

That's correct.

System

cts_casemod wrote: »

That's correct.

If they want an output of 4kW then the array has to be bigger than 4kWp as there are generation losses. My 2.15kWp array generates a max of 2kWs. Bear in mind, that from October through until March, a 4+kWp array will not produce anywhere near the maximum possible. Moreover, my monthly output in January was only 34kWhs compared to 220kWhs last month.

cts_casemod

Hengus wrote: »

If they want an output of 4kW then the array has to be bigger than 4kWp as there are generation losses. My 2.15kWp array generates a max of 2kWs. Bear in mind, that from October through until March, a 4+kWp array will not produce anywhere near the maximum possible. Moreover, my monthly output in January was only 34kWhs compared to 220kWhs last month.

My Hengus,
You're confusing. The total daily generation should add up to 2-4KHh, that means the instantaneous generation is much less, typically 500W over the coarse of 4 to 8 hours.

I did got to the bottom of this tough.

It appears that yes, all the excess energy not used is dumped back into the national grid, but the meter does not account for it.The revenue is earned in the form of the FIT's which obviously require a certified installer (and hence the need for a second meter) The main meter knows power is going backwards but it does not subtract it from the total

So in effect, doing so one would give away free energy. Its a rip off at current prices, even with the FIT the consumer is essentially buying at 12p, on average, and selling at 4.6p... ouch!!

So it seems they would need some storage device to be able to harvest such energy, get an approved FIT installer or give up the idea altogether.

System

There has been considerable discussion about PV Solar storage on the Green and Ethical Moneysaving Forum. At the moment, it is not cost effective for the average home user.

As far as generation is concerned, bear in mind that the highest demand is in Winter when the days are short and the sun is low. This is my daily recorded kWH over a few days in early December last year (on a 2.15kWp system)

2.4
2.1
0.2
3.5
0.4
0.6
1.6
2.8
2.8
0.1

The daily outputs are less in January and I rarely see more than 1kW unless it is a very sunny and clear day. My PVGIS target for December is 64.3kWhs. To get 120kWhs in December, I would need an array bigger than 4kWp. Conversely, yesterday, with the sun out, my array generated an output of 12.3kWh.

If the cost of storage was worth it, we would all be buying batteries and re-charging them overnight on E7 off peak and not bothering with PV solar.