Solar PV and home battery = crazy electricity bill!

Petriix

Congratulations. At £400 in savings per year, the powerwall will pay for its self in only 20 years (just double its expected usable lifetime).

You might well do better on Agile or Go but the standing charge is not insignificant. The problem is that there is only a certain amount you can save and you have invested maybe 10 years of your electricity bill into a device that could never (even at the hypothetical maximum) save as much as you spend.

Don't get me wrong, it's an awesome piece of kit and I'm appropriately jealous. I just can't see how it would be economical. I'll stick with exporting my surplus to the grid knowing that I'm saving CO2 even if I'm not using it myself.

gzoom

Petriix said:

Congratulations. At £400 in savings per year, the powerwall will pay for its self in only 20 years (just double its expected usable lifetime).

You would be correct if I had paid for the PowerWall, 

Infact we didn't even pay for the solar PV setup, it wasn't factored in at all when we put the offer in for the house!!

Once battery prices come down more, which they will I will be adding more solar PV + battery to the house, but for now am very pleased at how the setup works.

Petriix

Ooh, nice! Free definitely reduces the time to break even.

Smodlet

Great, you have almost zero electricity costs for no initial outlay, if I have interpreted correctly.  I think this is a fairly unique situation; do not most have the initial outlay to off-set against any potential savings?  Good for you for being so eco-friendly.

JC_Derby

gzoom said:

Petriix said:

Congratulations. At £400 in savings per year, the powerwall will pay for its self in only 20 years (just double its expected usable lifetime).

You would be correct if I had paid for the PowerWall, 

Infact we didn't even pay for the solar PV setup, it wasn't factored in at all when we put the offer in for the house!!

Once battery prices come down more, which they will I will be adding more solar PV + battery to the house, but for now am very pleased at how the setup works.

Unless you have a three phase incoming service you may struggle to just add more equipment, it would require a further application from your installer prior to installation to the DNO. 

gzoom

^We do have a 3phase supply!!

Only found out when the electrician pointed it out. But just on one phase at the moment.

Jaffa_cake

MWT said:

In part though the savings are good because the tariff is bad, 16p/8p isn't hard to beat by a considerable margin in most regions.

I thought 8p for E7 was reasonably good ?
What lower costs have you seen for E7,or shorted hours, eg 4 - 5 hours of super cheap electricity \?

John_Pierpoint

Don't forget there is 5% tax on charges for imported electricity.