Thursday, April 05, 2007

Electric Dreams

Johan Hari has an article in today's Independent called "Big Oil's vendetta against the electric car."

You have to admit that Johan Hari writes a good conspiracy. A lot of what he says is true, but it’s only part of the story. Electric cars are clean and silent, but only because the pollution and noise are generated at the power stations. Over 50% of the energy input to a conventional power station is lost in the process and more energy is lost as it travels across the grid, making electric cars very inefficient. Of course he may claim that we should be using green energy, but we would need to double our total electricity output to meet our transport needs. With only 4% of electricity coming from renewables at present – mostly from landfill gas and waste incineration – there is a long way to go.

The capacity of the grid would have to be doubled as well; will Mr Hari accept twice as many pylons? The other problem is that many of us have to park on the street and could not plug in our cars “like a mobile phone.” However, assuming you could charge your car and drive from London to Scotland as he claims, a 300 mile range would still leave you 100 miles short of Edinburgh.

The quoted fuel economy is impressive. Mr Hari tells us that he can buy the electrical equivalent of a gallon of petrol for only 30p. Given that a gallon of petrol contains 36kWh of energy, that is equal to less than 1p per unit. Can he tell us the name of his power supplier?

Wednesday, April 04, 2007

Coal on a Roll

The UK’s carbon emissions are rising. Ten years ago they began to decline because of the ‘Dash for Gas’. Coal-fired power stations were closed and new, clean gas stations took their place. Ten years on gas is more expensive and more and more of it has to be imported. Some say that we will be importing 80% of our needs as early as 2015.

The problem is that UK demand for gas continues to grow and so does world demand. With the power industry accounting for a third of the UK’s carbon emissions the choice of fuel for generators has a direct effect on whether the UK meets its targets. Coal is cheaper at present and government subsidies for desulphurization plant mitigate the cost to some extent. Clean coal requires investment to deal with carbon emissions as well as the sulphur and other pollutants. Powerfuel plc has recently entered into a joint venture with KRU, one of Russia’s largest coal producers To re-open Hatfield Colliery in South Yorkshire and build a clean coal generating station. The unit will produce gas from coal slurry, treat it for impurities and burn it to generate electricity which will be sold to occupants of a new business park planned for the site, and to the grid. By-products will be sold to the pharmaceutical industry.

Carbon sequestration – the storage of CO2 from conventional generation - in mines, spent oil wells or at the bottom of the sea; is theoretically possible but not yet in commercial operation. To make it a reality will take time and public money. With a five to ten year lead-time on major power stations we probably won’t have these systems in place in time to meet the targets. There may be a problem raising the money as well. It will all come from taxation, of course, but there’s still a great deal of resistance from the man in the street to spending money on going green!