I'm not convinced that the linkage between demand and price is that tight, TBH. The price is very heavily distorted by several factors, not least being the way that the bidding process works and the arbitrage that enables storage facilities to earn a decent revenue. There's also a lot of evidence that some suppliers are massively loading the price of off-peak electricity as a dodge around the price cap - they are choosing to rip off off-peak customers to reduce their published headline tariffs, IMHO.marshman wrote: ↑Wed Nov 16, 2022 9:55 am Don't disagree that the actual demand shift will be tiny, but we have already seen the erosion of the price differential between the E7 night rate and the day rate. And many members on here "pull" a lot more than 3kW for 4 hours (I appreciate that was to illustrate the small effect!), as they are not only charging batteries, but their EV and their storage heaters as well, something that was not happening just 2 years ago.
My point was that in my opinion PV is a safer bet on the return front than just relying on batteries for time shifting. I suspect there will be a significant proportion who have installed them to cover the possibly rolling power cuts that "may" happen this winter - and do the "man maths" to justify the cost. I know of at least two households getting batteries and inverter without PV for exactly that reason.
As an example, our suppliers E7 tariff this time last year was 7.56p/kWh off-peak, 27.773p/kWh peak. When the "54%" price cap came in on April 2022 prices, the tariff changed to 17.831p/kWh off-peak, 33.26p/kWh peak. They chose to more than double their off-peak rate in order to generate revenue to subsidise their peak rate. Other suppliers have done much the same, the only supplier that seems to be an exception is, I think, Octopus.
The demand ratio between peak and off-peak hasn't changed, so there has to be another explanation for our supplier choosing to change from a ratio where the off-peak price was about 27% of the peak rate to one where the off-peak price is now nearly 54% of the peak rate.