The Lemon Fool

AF62 wrote:Didn’t I mention, they are aircon units.

Arrgh.
One of the positives in the UK as regards energy usage has been the absence of aircon in the average home.
Once people realise that these can cool as well as heat, that will prompt a huge increase in our summertime energy usage.

Great!
Not....

V8

88V8 wrote:

AF62 wrote:Didn’t I mention, they are aircon units.

Arrgh.
One of the positives in the UK as regards energy usage has been the absence of aircon in the average home.
Once people realise that these can cool as well as heat, that will prompt a huge increase in our summertime energy usage.

Great!
Not....

V8

There is a huge amount of misinformation and misunderstanding circulating about heat pumps.

Yes the cheapo air-to-air heat pumps which cost a £k or two or three can often do cooling, but they can't heat your hot water so not many people want them.

The more sophisticated air-to-water type will heat a hot water tank but need bigger radiators as they rarely heat water to more than about 55C, and gas CH rads everyone has already fitted are generally sized to work with 80C water.

In addition, lots of houses have combi boilers and heat pumps don't have the power to work like combis. A hot water cylinder is mandatory and lots of combi owners are going to be highly resistant to this!

Finally the gear that needs installing for an air-to-water heat pump is HUGE. Here is a pic of the newest offering from Worcester:

(Slightly misleading photo as a big thing on the right like a washing machine goes in your garden, not inside your house.)

Mike4 wrote:Yes the cheapo air-to-air heat pumps which cost a £k or two or three can often do cooling, but they can't heat your hot water so not many people want them.

Or you could just use an immersion heater...

Mike4 wrote:The more sophisticated air-to-water type will heat a hot water tank but need bigger radiators as they rarely heat water to more than about 55C, and gas CH rads everyone has already fitted are generally sized to work with 80C water.

In addition, lots of houses have combi boilers and heat pumps don't have the power to work like combis. A hot water cylinder is mandatory and lots of combi owners are going to be highly resistant to this!

Finally the gear that needs installing for an air-to-water heat pump is HUGE. Here is a pic of the newest offering from Worcester:

(Slightly misleading photo as a big thing on the right like a washing machine goes in your garden, not inside your house.)

So fine if you live in a substantial new build property in the country away from neighbours where the radiators and pipes can be built in from new, you have the space for the external heat pump, and the noise from the heat pump isn't going to annoy your neighbours. And it is probably cheaper than oil as you won't be on gas.

For everyone else, as much use as a chocolate teapot.

AF62 wrote:

Mike4 wrote:Yes the cheapo air-to-air heat pumps which cost a £k or two or three can often do cooling, but they can't heat your hot water so not many people want them.

Or you could just use an immersion heater...

Or you could just use electric heaters for the whole house.

Or have you forgotten the point of a heat pump?

Mike4 wrote:

AF62 wrote:

Mike4 wrote:Yes the cheapo air-to-air heat pumps which cost a £k or two or three can often do cooling, but they can't heat your hot water so not many people want them.

Or you could just use an immersion heater...

Or you could just use electric heaters for the whole house.

Or have you forgotten the point of a heat pump?

Not at all.

But heating water overnight using cheap electricity and storing it in a well insulated tank until it is needed is quite effective, reasonably energy efficient, not too expensive to run, cheap to install, and 'green' in that uses electricity rather than gas.

Heating a home with electricity on the other hand would mean storage heaters which are not effective or efficient for most people's lifestyle of being out for most of the day so you need the heat retained for many hours, and you are particularly vulnerable to sudden changes in the weather which might mean that more heat than has been stored is needed if the temperature falls or less heat is needed (and so goes to waste) if the temperature rises.

AF62 wrote:

Mike4 wrote:

AF62 wrote:
Or you could just use an immersion heater...

Or you could just use electric heaters for the whole house.

Or have you forgotten the point of a heat pump?

Not at all.

But heating water overnight using cheap electricity and storing it in a well insulated tank until it is needed is quite effective, reasonably energy efficient, not too expensive to run, cheap to install, and 'green' in that uses electricity rather than gas.

Heating a home with electricity on the other hand would mean storage heaters which are not effective or efficient for most people's lifestyle of being out for most of the day so you need the heat retained for many hours, and you are particularly vulnerable to sudden changes in the weather which might mean that more heat than has been stored is needed if the temperature falls or less heat is needed (and so goes to waste) if the temperature rises.

You could heat a home using a thermal store, for example the Gledhill Electramate. Store heat energy using cheap rate off peak electricity at night and pump it around the rads during the day.

But the point of a heat pump is to reduce the amount of generated electricity (energy) used to heat one's house (and heat one's hot water) rather than just make it cheaper, is it not? Or have I got the wrong end of the stick? Or the wrong stick even?