Immersion boost & Tesla Powerwall

[Oldgreybeard]

Be absolutely brilliant for us if the overnight price comes down. Just checked our data, and so far this year 98.4% of our total electricity usage has been at the night rate. All I'm now really interested in with any tariff is the night rate and the standing charge, as any change in the day rate has such a miniscule impact that it's not worth worrying about.

It's not often that I get lucky, but making that decision a couple of years ago to buy far more batteries than I thought we would need is one of those very, very lucky times. I have @Nowty to thank, in part, as I first started thinking about putting a battery system in when lurking (as a banned person!) on the old place. Even then I ummed and ahhhed for many months before biting the bullet and buying the batteries. For a time back then I wondered if I was doing the right thing, as the difference between the day and night tariff wasn't much. IIRC we were then paying around 15p/kWh day rate and 11p/kWh night rate, not enough on its own to cover the cost of getting the batteries.

Earned a LOT of brownie points from SWMBO this year, though. She's been keeping an aye on the bill and keeps reminding me what a good decision "we" made to get the batteries. As I remember it, I had to do a fair bit of persuading to get her to agree that spending so much of our savings on them would be a good thing!

[Ken]

Using FF be it gas or oil can never be cheaper than leccy in the non CH period due to the efficiency being 50% or less with a tank system due to stop/start losses,pipe losses and dead leg losses.

In the non CH period the best technique for me is to just boost the immersion immediately before use and only by a small amount thus leaving room for the pv to do it later on.