- Joined
- 27 Jan 2008
- Messages
- 24,891
- Reaction score
- 2,876
- Location
- Llanfair Caereinion, Nr Welshpool
- Country
My biggest gain was the battery and using off-peak supplies, you can't do that without an inverter, so you may as well have solar panels as well, and the solar panels reduce the size of battery required. The South-West is the important angle, as it is evening when one is likely to run out of battery. But this
is typical state of charge curve for the battery, the drop 5 am to 12 noon rarely gets near to the 10% cut off point, the evening it happens less now with 6.4 kWh to what it did with 3.2 kWh, but that curve can easy hit the 10% cut off point (reserved for UPS in case of power failure) before end of day. Yesterday for example
ran out of battery before end of day, and unlikely any amount of solar panels can help when there is a lack of sun.
It is easy to miss judge the day, showing all factors
we did do some cooking which did not help, but there is a balance, my batteries have a guarantee for 12 years, so need to pay back in that time, solar panels can last a lot longer, so to have enough battery not to ever use peak power would not pay, I expect as the days get shorter to have more and more days when the battery does not last out, I with my system have an option of 1 to 4 batteries, at fitted £1,200 each, and they are 3.2 kWh each, one was essential, but as to second, waited a year to see how it went, then got the second, once sure it would pay for its self. I don't think will ever be worth getting a third or forth unless I get more payment for export to what I pay for off-peak.
is typical state of charge curve for the battery, the drop 5 am to 12 noon rarely gets near to the 10% cut off point, the evening it happens less now with 6.4 kWh to what it did with 3.2 kWh, but that curve can easy hit the 10% cut off point (reserved for UPS in case of power failure) before end of day. Yesterday for example
ran out of battery before end of day, and unlikely any amount of solar panels can help when there is a lack of sun.It is easy to miss judge the day, showing all factors
we did do some cooking which did not help, but there is a balance, my batteries have a guarantee for 12 years, so need to pay back in that time, solar panels can last a lot longer, so to have enough battery not to ever use peak power would not pay, I expect as the days get shorter to have more and more days when the battery does not last out, I with my system have an option of 1 to 4 batteries, at fitted £1,200 each, and they are 3.2 kWh each, one was essential, but as to second, waited a year to see how it went, then got the second, once sure it would pay for its self. I don't think will ever be worth getting a third or forth unless I get more payment for export to what I pay for off-peak.
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