The battery systems are a benefit so i would expect the suppliers to try and lower the profit made by the consumer soon.
Battery systems in private houses might make a profit but profit might take many years to recover the cost of the system.
No one locally has asked the Nephews to install any yet. They gave up solar installations when the profit to the customer dipped. Solar installaion just fell flat back then.
In a modern wiring installation, a socket in the bathroom is permitted as long as its out of reach of the water with a screen. Still not a good idea but i have one to run my pump but its within a sealed box away from any water.
My general heating temperature in the house needs to be 19C downstairs but about 17C up in the cold Winters. Very rare i use a gas fire now since the insulation went in. I also have thermal curtains and blinds to help with window heat loss.
My gas bill is relatively low as my next door neighbours heat comes through the party wall and he switches it on at 6am.