WSP Engineering group have carried out some interesting research into the potential of the Electric City. The basic principle is that we should move away from combustion within cities for heating homes, buildings, generating power, cooling or transport, and rely on electrons instead.
The potential benefits are staggering. The future city powered by electricity has a much better environment for its inhabitants with lower emissions and fewer particulates in the air, the air is cleaner because much of our air quality problems stem from combustion in boilers and engines. The city is quieter because electric motors are quieter than combustion engines. The city produces less CO2 emissions because heat pumps are more efficient than boilers and electric cars are more efficient than combustion engines.
WSP calculate that if we aimed to create an all-electric London by 2030 we could have
– reduced NOx levels by 37%
– vehicle noise levels will be reduced by 25-50%
– electricity usage in the capital would double from 40k GWh to 80k GWh per year
– CO2 emissions would drop from 88 MtCO2 to around 8 MTCO2 per year, a drop of around 90%.
SAP, the tool used to assess the compliance of UK housing for Building Regulations, uses a CO2 factor for UK Grid electricity based on a three year average prediction of the Grid emissions. What WSP’s work makes clear is that this is the wrong period to use for predictions. The long term predicted emissions for the UK Grid is for it to be lower than gas, and to reach this point before 2020. Using a ‘dirty’ Grid emissions factor now, means that we are installing gas CHP and gas boilers in the anticipation that they will drive down CO2 emissions. But during the lifetime of these systems the Electricity Grid emission will drop below gas and continue to drop until it is much lower. So installing systems now that have a twenty or thirty year life of predicted emissions is actually likely to raise emissions rather than reduce them.
A major issue for housing in all of this is that currently it is much cheaper to heat a home using gas than electricity, because electricity is three times more expensive. The problem we need to solve is how to reduce heating demand to a point where new homes can be heated by electricity for the same amount of money as other homes on the market can be heated by gas. There are well documented problems where newish homes were heated by heat pumps resulting in higher than average bills because the homes simply weren’t efficient enough. Perhaps we need to look again at dual tariff electricity supplies to new homes using off peak electricity to drive heat pumps?
With cars the picture is different because petrol is so much more expensive than gas, electric driving is a much cheaper option, so it is entirely likely that electric transport will lead the electric revolution faster than the construction industry. Cars have a shorter life than building services, so the replacement rate for cars will mean that technological changes will be introduced more quickly in any case.
Whatever the outcome this is an excellent piece of work, and highlights the benefits of taking a long term view of energy policy and market intervention.