Our electricity consumption for the last month was £55.89, including the daily charge, (useful things, smart meters!), for the same usage as yours, for two adults – except our shower uses gas heated water from the tank. So I might be looking carefully at other providers soon, since we are obviously paying a little too much !

Your comment about heat pumps is possibly valid today – and puts me off as well – but will we think the same when the price of gas or oil has gone up 3 fold or whatever, as governments around the World attempt to wean us off fossil fuels to meet emissions requirements ?

I think part of the very high price of heat pumps is that those quotes assume that not only the boiler is changed – the entire heating system is ripped out and new 'everything' is installed:- underfloor heating, or larger radiators, larger super-insulated hot water storage tank etc. I heard that tanks in the loft also need to be put back in, many having been taken out when converting to condensing boilers, but am not sure why this would be.

.

Edited By John Doe 2 on 27/09/2023 14:49:12

You need a hot water storage tank with heat pump ad it can't do instant hot water like combo boiler. You might also need bigger radiators as the temperature of the heating water is lower. I'm not sure why they don't use hot air heating with new builds, then the lower temp wouldn't matter as much. Difficult to back fit unless you have a bungalow in which case the ducting could be in the loft. You could then incorporate a heat exchanger and bleed some of the circulating air to the outside, reducing humidity and do condensation in the house.

Edited By duncan webster on 27/09/2023 15:01:31

Boiler Upgrade Scheme | Daikin

My house/workshop has been off-grid since Dec 2022 reliant on PV solar energy. Monthly usage averaged 1300KW over winter, with 2500KW generated. The excess is exported to the Electricity supplier at 60% consumption value.

I have hot water underfloor heating, which used to run from a solar heated water system, heating a 6000liter insulated water tank, buried in the ground. That heated water ( around 30degC in winter end of day) fed a 3phase 14KW boiler, and then into the pipes in the floors. The boiler was used during many low/no-sun days in winter.

In winter my floor heating energy used was around 50KW/24hour period – I did not run the boiler during day time, since electricity costs are almost double between 10H00 and 18H00. So the floors cooled during the day, and extra energy was needed at night to re-heat.

When I fitted the PV system ( 3phase, 28KW PV capacity) I fitted a Stiebel Eltron heat pump – a 3phase pump, with a variable speed compressor, to heat the floors.. The pump is capable of 12KW output, and is an Air extraction pump.

Since I heat the floor water to 35deg C max, and the floor water return temp is never below 20degC, the delta the heat pump sees is a max of 15deg, at start of heating, with the delta reducing as the floor heats up to 25deg setpoint.

All that gives me a pump COP of 10 (!) and I run day and night, so the floors don't cool in the day. That returns a daily heat output of around 33KW, with a consumption of around 3KW…

My monthly usage for floors in now around 100KW, instead of 1500KW – and THAT ticks all the boxes – energy cost, carbon footprint, comfort….

Lower COP's are to be expected if the water heating temp differential is higher, such as heating water for showers, etc ( 50degC plus..) – but this heat pump delivers a COP of 4 to 5 when doing that…

The heat pump did cost around 8K British Pounds…but is better than sliced bread.

Electricity

Standing Charge Per Day – 51.48

Night – 16.31 p/kwh

Day – 35.33 p/kwh

Gas

Standing Charge Per Day 26.16 p/kwh

Dy/Night = 7.24 p/kwh

There is more than one type of heat pump. I assume you are referring to the air to water type currently being promoted by the government. These have a issue that they don't produce very hot water so the whole system needs updating and probably larger pipes and radiators.
I've had heat pumps in my last two properties for over twenty years. These were / are air to air type units that provide heat in the winter and cooling in the summer. Heating is cheap and you don't have to use the cooling. The only downside is you need another means to supply hot water. I use an instant flow gas heater and an electric shower. You can also get electric instant flow heaters. The advantage of these is you are not loosing heat from stored hot water. YMMV but they are worth a look.

Robert.

Before people get excited by various electricity rates getting quoted on here bear in mind the rates depend a lot on town/country, area of the country etc.

MG you could consider building a nice detached workshop, I mean summerhouse outbuilding, the max size permitted first and use it to store the house 'stuff' for a while while making other developments. Then afterwards you have er, a nice workshop.