Should I get a night time tariff?

waqasahmed

I've got 8 solar panels, and a piddly little 3.3KwH battery. I was wondering then if I should use a might time tariff?

Or should I wait? I aim to get my flat roof reinforced, add another 8 panels and more batteries once the flat roof is reinforced too. I've already bought an inverter that can handle that 16 panel capacity 

QrizB

My back-of-an-envelope calculation suggests that, with a battery that size, if you're using less than about 8kWh a day you'll probably make a saving in the winter by charging the battery off-peak on E7.

If you're using more than that, the higher price of daytime E7 is likely to exceed the savings.

Once we get into lat February and your solar panels can meet more of your daytime load, the balance will swing and E7 charging starts to make sense with higher daily consumption.

waqasahmed

QrizB said:

My back-of-an-envelope calculation suggests that, with a battery that size, if you're using less than about 8kWh a day you'll probably make a saving in the winter by charging the battery off-peak on E7.

If you're using more than that, the higher price of daytime E7 is likely to exceed the savings.

Once we get into lat February and your solar panels can meet more of your daytime load, the balance will swing and E7 charging starts to make sense with higher daily consumption.

Thanks. I'm currently averaging around 11 KwH, so I guess it only makes sense once I've got at least one more battery? 

powerful_Rogue

waqasahmed said:

QrizB said:

My back-of-an-envelope calculation suggests that, with a battery that size, if you're using less than about 8kWh a day you'll probably make a saving in the winter by charging the battery off-peak on E7.

If you're using more than that, the higher price of daytime E7 is likely to exceed the savings.

Once we get into lat February and your solar panels can meet more of your daytime load, the balance will swing and E7 charging starts to make sense with higher daily consumption.

Thanks. I'm currently averaging around 11 KwH, so I guess it only makes sense once I've got at least one more battery? 

We use on average 10kWh a day. 13kWh battery charged overnight covers this nicely.

waqasahmed

powerful_Rogue said:

waqasahmed said:

QrizB said:

My back-of-an-envelope calculation suggests that, with a battery that size, if you're using less than about 8kWh a day you'll probably make a saving in the winter by charging the battery off-peak on E7.

If you're using more than that, the higher price of daytime E7 is likely to exceed the savings.

Once we get into lat February and your solar panels can meet more of your daytime load, the balance will swing and E7 charging starts to make sense with higher daily consumption.

Thanks. I'm currently averaging around 11 KwH, so I guess it only makes sense once I've got at least one more battery? 

We use on average 10kWh a day. 13kWh battery charged overnight covers this nicely.

Thanks. I guess I'll wait until my other panels + batteries are in then. May I ask what solar panel system size you have?