Electric Heat

UK natural gas production is in steep decline. We use natural gas in Scotland for heating. 85% of homes in Edinburgh are heated using natural gas. The fact that our own domestic prduction is in rapid decline and that our natural gas imports are rising should give us cause for concern.

Our gas is increasingly being imported by ship from Qatar in the middle east. The gas is transported in liquefied form - Liquefied Natural Gas (LNG). It is likely that we will have a glut of gas in the UK in the next two or three years, but after that the outlook is not so clear.

Perhaps we should use electricity for heating? After all, we have loads of renewable electricity generating capacity coming on stream.

Well, that's not a bad idea, but if we all switch to conventional electric heating, the electricity grid will not be able to cope.

So, I propose that we ban the following

• electric immersion heaters,
• electric power showers,
• electric fires,
• electric tumble dryers,
• electric storage heaters.

What? We're running out of gas for heating and you propose to ban just about every electric heating device known to mankind?

Yes. Because all of these old fashioned ways of producing heat are very inefficient. We can do better. Way better.

How? Using heat pumps.

What's a heat pump when it's at home?

Well, you already have one at home, more than likely. In the fridge. It takes warmth from the inside of the fridge and dumps it into the kitchen, making the inside of the fridge cold - about 5 degrees centigrade - and the kitchen very slightly warmer.

A heat pump uses the laws of thermodynamics to move heat from one location to another.

Heat pumps can be used to heat water or air. The hot water or hot air can be used to do the jobs of all the equipment I proposed to ban in the list above.

But much more efficiently. Much, much more efficiently.

A gas boiler is about 80% efficient. It converts about 80% of the energy in the gas into heat. Not bad. An electric fire is 100% efficicient. It's just a big resistor and converts all the electrical energy it receives into heat.

But, a heat pump may be 200%to 400% efficient.

It achieves these efficiencies by using electricity to move low grade heat from the environment (from the ground, air or water) into the home. Heat pumps can deliver hot water at 65 degrees centigrade without the use of electric immersion heaters. They can be used to heat the average house.

Heat pumps win hands down in the efficiency stakes.

But, we need to be careful as not all heat pumps are the same.

A new breed of air source heat pump has just arrived in the UK whose performance is far superior to those currently on offer. We're going to have a talk about these units at the Energy Fair on the 5th Septermber 2009.

And although not available yet in the UK, air source heat pumps are beginning to be used in clothes dryers greatly improving their efficiency.