Air Source Heat Pump
By Ray Bate
I want to tell you about an alternative energy or renewable energy device that we will all hear more and more about as time goes on. This amazing device is the Air Source Heat Pump; maybe you have never heard about it but it is nothing more basically than a ‘back-to-front fridge’ (refrigerator) and could be your route to a warm house at next to no cost! Interested?
Think about your fridge:
- There is a Compressor Pump driven by an electric motor which pressurizes the cooling vapour and causes it to condense back into liquid. This condensation causes the emission of heat (Latent Heat) in the External Pipe Coils at the back of the fridge – they get noticeably warm and give heat to the atmosphere, as the pressure drives the cooling vapour through these and then, as liquid through ….
- The Expansion Valve – the liquid coolant passes the Expansion Valve and evaporates to form vapour. This expansion causes severe cooling in the Internal Pipe Coils which surround the interior space for foods, solid and liquid. Consequently (Latent) heat is taken from this space, and all the food and drink in it, are cooled down.
- Then the cooled vapour reaches the Compressor Pump and the process continues as before – the heat is taken out of the ‘food box’ and rejected into the surrounding air, simple isn’t it!
Now, in a stroke of genius in my opinion, because of the simplicity, someone decided to stretch the pipes just a little and call our fridge an Air Source Heat Pump…
- Now the Internal Pipe Coils are put outside in the garden, and the External Pipe Coils are put in your house.
- As before, the Compressor Pump pushes vapour through the ‘house pipes’ and heat is given out as the vapour condenses into liquid. This heat can be used to heat the house!
- As before, the liquid passes through the Expansion Valve and evaporates into vapour, cools severely as it passes through the Internal Pipe Coils (in the garden) and takes in heat from the surrounding air, which is relatively hot, even if below freezing temperature in winter – because the evaporation drop is much greater (-32°C). There is always more heat in the air outside, which is continually replaced. (Except in very severe winter conditions, where temperatures go consistently way below freezing).
- So, heat is drawn out of the air around the ‘garden’ coil and given out from the ‘house’ coil; this may then be used directly as hot air heating or eg. to heat water in a typical water filled ‘radiator’ system.
There is no boiler, no dirty emissions into the atmosphere, the running cost is for the electricity to drive the Compressor pump and the circulating pump in the house. (Perhaps you can use a solar panel or Aeolian wind turbine to generate the electricity)! Depending on the weather conditions of your location, these heat pumps can produce 5 times or more heating than the electrical consumption of the pumps! SIMPLY AMAZING!
About the Author:
Ray Bate is a physics graduate with years of experience of navy high tech systems engineering, then consulting for European Space agency satellites including solar panels, electronics and software systems. He is now very interested in the evolving and increasingly important Alternative Energy or Replaceable Energy, eg. Solar, Eolian and Geothermal Heat Pumps. Visit http://alert-alternativeenergy.com.
