PV and Storage Heaters

Cardew

I too would be interested in the cost of a 3.9kW system -£20K??

I would be very surprised if you can use 50% of that output. Approx 2kW all day every day?

Even people with systems much smaller systems fail to use 50%.

zeupater

Cardew wrote: »

I too would be interested in the cost of a 3.9kW system -£20K??

Hi All

Well, with the massive increase in interest in PV systems resulting from the introduction of FITs I suppose that there are many people who will be asking exactly that question.

Perhaps it's time for a sub-forum specifically to compare installation costs and quotations for PV system installations ... possibly someone would be prepared to maintain a restricted access summary thread to provide a rolling commentary on current costings & developments .....

Any interest or consensus ? ......

Cheers ....

MisteRusty

albyota wrote: »

have you had quotes for your 3.5kWhp solar PV array yet, if so could you share the info, i.e. make/number of panels, poly or mono, inverter? fronius/SMA etc?

Here’s my system spec :-
17 x 230W Yingli polycrystalline panels
2 Fronius inverters (panels are on 2 different roof pitches)
Total cost £14742
I was lucky enough to get a grant application accepted on the final day, so total cost will be reduced by £2500.

Expected kwh pa 2920

The panels are now installed, and the inverters are due in a couple of weeks.

Cardwe wrote:

I would be very surprised if you can use 50% of that output. Approx 2kW all day every day?

The 3.9 refers to the peak production, ie sunny Summer afternoon and it will not produce this constantly.

The Average daily production will be 2920 / 365 = 8kwh per day
But this is not adjusted for seasonal sun strength nor winter cloud.
The reality might be 1 kwhr per day average in Dec and 16 kwhr per day average in June.

The 50% figure is based on EDF's export tariff (ie 3p per kwh for 50% of the total generated) as I've not found any real data from other installations.

zeupater wrote: »

Perhaps it's time for a sub-forum specifically to compare installation costs and quotations for PV system installations ... possibly someone would be prepared to maintain a restricted access summary thread to provide a rolling commentary on current costings & developments .....

This might be a great place to collate output and usage data.

Cardew

MisteRusty wrote: »

The reality might be 1 kwhr per day average in Dec and 16 kwhr per day average in June.

This is a useful tool to calculate monthly output.


http://sunbird.jrc.it/pvgis/apps/pvest.php

Cardew

MisteRusty wrote: »

Here’s my system spec :-
17 x 230W Yingli polycrystalline panels
2 Fronius inverters (panels are on 2 different roof pitches)
Total cost £14742

The panels are now installed, and the inverters are due in a couple of weeks.

Is that the total fitted cost?

zeupater

MisteRusty wrote: »

This might be a great place to collate output and usage data.

Hi

How do we go about setting up a sub-forum then as setting up a single thread will undoubtedly lead to a certain level of 'misleading' posts as diversions on this issue ....

Regards.
Z

Anyone ?????? ..... admin ?????

MisteRusty

Cardew wrote:

This is a useful tool to calculate monthly output.

Many thanks, looks like a really useful tool.

Cardew wrote:

Is that the total fitted cost?

Yes, that's the total cost. I had several quotes for different panels including Sharps, Sanyos, Kyocera and Romags and the Yingli's were the most cost effective (£ per kwp).

Some of the others were quite close though and I had 4 quotes which were less than £16500.

Kontiki

Came to this thread while looking at the same issue - PV solar panels & getting the maximum benefit by using some sort of electric heaters. Looks like we have a similar situation (PV of 3.9kw & gas combi heating)

I am due to get my PV system installed in just over a weeks time. My system will be 3.885 Kw (Worldwide Energy and Manufacturing USA inc. AS-5M-185W x 21 panels) Cost of installation is just under £13k (said I wanted a quote starting with £12k). I had in all 5 quotes ranging from £13280 to £15k (EON was around the same but for a much smaller array) & the first one was the cheapest & I managed to get it down a bit more. I think I could have gotten at least 2 of the others to match or even better this. The guy I went with in the end has already done a similar installation on our estate (a local councilor who was eager to talk about his set up) At the moment he is also getting the benefit of having an old style meter installed & when his panels are producing the meter goes backwards :T.

Back to the point has anybody come up with a good cost effective solution to being able to use the electricity to power some sort of heating (electric radiators/storage etc.) the idea being to store some of the free electric as heating to offset the gas central heating. I was thinking about something like a storage heater with possibly a some sort of small solar panel to turn it on (my problem I don't have the electrical knowledge to set it up) We tend to go away during the winter in our motorhome & would like some automatic heating system (obviously free) to keep the chill off the house.

Cardew

Kontiki wrote: »

Back to the point has anybody come up with a good cost effective solution to being able to use the electricity to power some sort of heating (electric radiators/storage etc.) the idea being to store some of the free electric as heating to offset the gas central heating. I was thinking about something like a storage heater with possibly a some sort of small solar panel to turn it on (my problem I don't have the electrical knowledge to set it up) We tend to go away during the winter in our motorhome & would like some automatic heating system (obviously free) to keep the chill off the house.

There is no way unfortunately of 'matching' the power output of your panels to the consumption load of your house.

I think you might be surprised at just how low the output can be on a cloudy winter day - perhaps as low as 0.1kW at times.

The problem is that even if you have a very low powered heater like, say, a 0.5kW oil filled radiator, you will find that 80% of the power it uses will be coming from the mains at times when the panel's output is very low.

grahamc2003

MisteRusty wrote: »

Many thanks.

It's certainly true that hot water would be more useful for more of the year. However, I reckon the cost of modifying my combi boiler based system will be in the £000s whereas as 2nd hand storage heater may be less than £50.
Even if it's not running over the summer, my feeling is it's going to be more cost effective, so I think I'm going to go with it and monitor the results. Might wait till the autumn though before I go shopping, and get some better data first !

You yourself have pointed out the catch22. You'll only have meaninguul amounts of surplus power for a few hours each day in the summer. Outside say those 3 months (when you probably won't need heating anyhow), I doubt you'd get a 1.5kw surplus much of the time (and 1.5kw is the smallest storage heater you'll find). That means it's likely you'll be pulling most or all of the 1.5kw from the grid at daytime rates - almost certainly in the winter, and for much of spring and autumn too). Fine if you would otherwise have heaters on at that time, not so fine if the only reason they are on is to soak up you're excess power (if any - remember you'll have some load at that time anyhow).

To use the surplus, you definately need some intelligent erquipment like the setup mentioned, which (I assume) monitors your generation and demand in realtime, and switches in additional load when theres a surplus, and dumps load when importing from the grid. I'd like to see how the kit works in practice in a domestic situation - but assuming it works well, the payback period looks pretty horrific.

(You'll be pleased to know that the grid itself faces a similar problem, in that it has to match total generation to total demand in real time - and it costs megabucks to do that).