Another 'leccy question

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llondel
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Re: Another 'leccy question

#21 Post by llondel » Tue Nov 30, 2021 9:34 pm

Boac wrote:
Mon Nov 29, 2021 10:12 pm
Out of interest, what sort of cost for a decent battery and 240V inverter?
That depends on what you want it to achieve. A 1kW computer UPS cost me just under $200 a few years ago but it has a couple of the small 12V 7AH SLA batteries inside which will survive no more than ten minutes on full load.In theory the same electronics, assuming it doesn't overheat if run like that for more than ten minutes) would run a lot longer with a larger battery, but would also take longer to recover because it's designed to charge the two smaller batteries.If you're looking at running 5kW then you're getting into serious money and a lot of battery. You'd probably want 48 or even 96V of battery because 5kW at 12V is 400A and you're wasting a fair bit heating up the wires.

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Re: Another 'leccy question

#22 Post by unifoxos » Wed Dec 01, 2021 9:30 am

On the bill for my recent installation the 5kW inverter was charged at £1230, the 8.2 kWh battery at £2500. There is a fair bit of extra kit itemised, isolators, meters etc, totalling around £200. If doing the installation oneself, you can buy this stuff a bit less than that from suppliers on the web. A good sparky could do it on a day - local reliable guy here charges £350 a day for labour only, includes his app. The batteries come in modules and this brand (givenergy) can be configured up to about 12 kWh.

I wanted a professional install to get the MCS certificate I need to get paid for exporting surplus solar from the panels, otherwise I'd have saved a few hundred by doing it myself. I was, however, originally trained to IEE standards when I started work and consider myself capable of doing mains work (we were trained up to 11kV) but it has meant keeping up with the regs that seem to be changing more frequenty these days.
Sent from my tatty old Windoze PC.

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Re: Another 'leccy question

#23 Post by Boac » Wed Dec 01, 2021 10:02 am

Thanks for all the info. Whilst I live in the (already 'levelled-up' Boris Land) and have a reasonably reliable elec supply, I am concerned at the recent severe hardships in the north of UK caused by the recent weather and feel a back-up would be a prudent consideration.

Cost-wise the genny route seems to be far more effective and would run for an unlimited time as well if needed and enable at least my gas powered c htg and a few lights to run.

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Re: Another 'leccy question

#24 Post by unifoxos » Wed Dec 01, 2021 12:57 pm

Very true - a self-starting genny of a suitable size for a house can be had used (which often means tested once a month for 5 years) for half the price. 'Course, theres a maintenance overhead - the monthly testing, annual oil and filter changes, keeping a good stock of fuel.....

Fuel is less of a problem if you have mains gas, of course.

I
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