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How do you pair a storage battery/solar and an Air Source Heat Pump?

Discuss How do you pair a storage battery/solar and an Air Source Heat Pump? in the Green Energy Forums | Green Energy Hub area at ElectriciansForums.net

i guess im trying to find out what a air source heat pump is and what power it draws at what time...and what it does with the power it draws from the mains electricity.....but even wiki didnt explain this......i googled a few times, but found nothing, then thought it must be too new for google.
 
i guess im trying to find out what a air source heat pump is
Really ?
Heat pump - Wikipedia - https://en.wikipedia.org/wiki/Heat_pump
and what power it draws at what time
It draws what it draws, when it's running. What it draws depends on it's rating and how hard it's working. That varies from "a few amps" up to "lots" (could be hundred of kW or even into MW territory). For domestic, probably anything up to (makes a w.a.g. and picks a figure from the air) 10-15kW electrical load.

As a quick rule of thumb, modern heat pumps tend to work at a CoP (Coefficient of Performance) of around 3 - give or take, depending on conditions. That means, for one unit of electricity in, you get about 3 times the energy out. But that's highly dependent on conditions. The higher the temperature differential between hot and cold sides, the lower it gets - some heat pumps actually switch to an immersion heater at very low outside temperatures as the CoP as a heat pump actually drops below 1. This is an issue as they are needed the most when it's cold outside, and the water temperature needed to heat a house goes up as the outside temperature goes down. So they are most efficient when you least need the heating.
This is why switching from a gas boiler to a heat pump may mean replacing all your radiators with significantly bigger ones. If you have an old system, it might have been designed for an old non-condensing boiler to run at 60˚C or higher. A heat pump is largely useless at these flow temperatures, so you'll need much larger radiators so you can run the system at 30˚ to 40˚C.
and what it does with the power it draws from the mains electricity
Vapor-compression refrigeration - Wikipedia - https://en.wikipedia.org/wiki/Vapor-compression_refrigeration
Very quick version : You have a chemical (there are many options) in two phases.
From the gas phase, you compress it, and you may recall from school science lessons that when you compress a gas it gets hot. You now have hot gas, which you use to heat something - and for heating, that would be water via a heat exchanger (the condenser).
When you extract heat from the gas, the combination of high pressure and reducing temperature causes it to condense into a liquid. Again, thinking back to school science you'll recall that there's an energy involved (latent heat) in condensing a gas to a liquid - and this also transfers to the water. As a result, out of the heat exchanger you get the refrigerant in liquid form.
The liquid returns via a pipe, and it's allowed to expand into a low pressure part of the system (I'll get to that). Again, latent heat is required and so you end up with a mixture of gas and liquid at a lower temperature and pressure. This mix is passed through another heat exchanger (the evaporator) - for an air source heat pump, it's the heavily finned "radiator" in the outdoor unit. Because the mix is cold, heat is extracted from the (in this case) air - allowing the liquid to evaporate.
At the other end of the heat exchanger is the suction side of the compressor. It maintains a low pressure in the evaporator circuit. It takes the cold gas and compresses it back into a warm high pressure gas - completing the cycle.

In theory you could pump heat with any gas without a phase change - but in practice the efficiency would be quite low and the system physically large. It's the phase change - evaporating and condensing the refrigerant - that does nearly all the work. It's a fairly small fraction of the heat that comes from cooling the hot gas to the point where it condenses.

Going back not too many years, the compressor ran all the time the system had to work (just maintaining a set low pressure in the evaporator), and the flow of liquid, and hence the flow of heat, got regulated by a valve. Now it's fairly universal that the compressor is run via an inverter and varies it's speed according to load.

There are a number of other methods, but this refrigerant cycle is used it pretty well all domestic systems. The main situation you'll find one of the others is if you have a gas powered fridge using the absorption cycle - fairly common in touring caravans where it's poor efficiency is of secondary importance to it's portability and not needing a high power electricity supply.
but even wiki didnt explain this......i googled a few times, but found nothing, then thought it must be too new for google.
From the first Wikipedia page : "1748: William Cullen demonstrates artificial refrigeration"
Not so new !
 
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