Zero carbon homes – what a gas!

Natural gas is used to heat around 80% of the United Kingdom’s homes. Most of the homes that are use gas to provide heat also use it to provide hot water, although I would guess (I have not be able to find any statistics) that a small proportion of gas users switch off their boilers in summer and get their hot water from an immersion heater in a cylinder. That means that 20% of the homes are off the natural gas network.

These homes  – around four and a half million of them -have to use electricity, heating oil or liquid petroleum gas, all of which produce around three times the amount of carbon dioxide and many more times the amount of particulate emissions than natural gas. If you have a top of the range gas condensing the boiler the quantity of emissions produced for heat per kilowatt hour is even lower. 

According to the latest energy statistics, the average home paid in the 12 months ended September 2007 £552 for gas and £383 for electricity. I think that these figures include value added tax. recent price increase will add around 16% to thie bill.

Clearly the four and a half million homes not connected to the gas network are the biggest polluters, as far as dwellings are concerned. They will also pay the biggest fuel bills, because electricity and oil and LPG is, per kWh, much more expensive than natural gas. In addition oil and coal and LPG have had larger price increases than gas and electricity.

What is the Government’s reaction to this? You would expect that it would develop a program to provide incentives to people off the natural gas network to use renewables, like solar panels and PV and turbines for heat and electricity, and possible also to extend the natural gas network. 

Well unfortunately we cannot expect things to be logical, can we? Mr Alistair Darling, (I expect he finds some time to look at these things when he is not being distracted by the Northern Rock crisis) has set out criteria to provide an incentive in the form of Stamp Duty relief for zero carbon homes. I have written about this before and make no apology for doing so again. 

The terms of getting the relief recognise that a “zero carbon home” cannot be zero carbon all the time so it must be zero carbon over a period of time, taking account of the export of locally generated electricity back to the grid.

Measuring electricity going in and out of a home is very different from the home being zero carbon; you have to take account of the overall position including transmission losses and the fact that sometimes the renewable electricity generated will be generated at times when it cannot be usefully used because the grid’s base load is adequate. 

Of course all these measurements and statistics and details are set theoretically at the start, when the home is built. Once you have got your stamp duty relief what is prevent the home occupier using more electricity than he or she generates? Er…nothing. They can have dozens of powerful appliances, leaving them on all day. There will be no device to limt the electricity that they can consume. 

If you have a zero carbon home it must not be connected to the gas grid. Under the rules a “zero carbon home” qualifying for stamp duty relief cannot be connected to the gas grid. This will make some interesting scenarios if anyone does actually try to build these in numbers because we all know that there are times when renewables cannot generate energy (including heat energy) and you have to have a back up. What will be the back up heat for a zero carbon home? Why – electricity and biomass, both of which produce much more carbon than …natural gas.

 It makes you question why people like Gordon Brown in his 2007 budget and Alistair Darling muddle incompetently in things that they do not understand and waste their time and our money devising nonsensical schemes. It would have produced much greater carbon savings to devise a special renewables scheme of those of the gas grid network, but the spinning opportunities would be much fewer than those under a grandiosely misnamed scheme called “zero carbon homes”. 

I can think of no more powerful demonstration of why we need an Energy Minister of Cabinet rank, advised by civil servants with the knowledge and intellectual capacity to get these things right.