Reducing CO2 emissions from UK transport will require a combination of measures, including increased fuel switching, energy efficiency, and new technology introduction. The main alternative technologies for motorised transport can be divided into vehicles and fuels.
At present, battery electric vehicles (BEVs) are zero emission, producing no tailpipe emissions in the course of their operation. BEVs that are recharged using energy sourced from renewable energy technologies are as close to being zero emission as possible (there are emissions associated with their manufacture). Even when BEVs are charged using standard grid electricity, they are still cleaner than all other cars on the road (1).
Battery electric vehicles consist simply of a large rechargeable battery which stores electrical energy and this coupled to an electric motor which drives the wheels. This combination is far more efficient than internal combustion engine powered cars and is the reason for their lower emissions. However, battery electric vehicles still face significant barriers which are likely to prevent mass production and major market diffusion in the medium term. In the longer term, these barriers could potentially keep BEVs within niche applications such as urban commuting, rather than allow them to enter the mass market. Currently the major limitation with BEVs lies in their short range. Many of the smaller commuter BEVs have ranges of around 30 to 60 miles (50 to 100 km), while some higher performance examples have ranges of 150 miles (240 km). Improvements in the energy to weight ratio of the battery would enable BEVs to have a range comparable to internal combustion engines and increase their marketability. In addition battery charging time is still high for most customer expectations, unless fast charging is used which would require more complex and considerably more costly charging stations.
In London, the growth in short range commuter EVs has been very strong. Westminster Council has installed in 2006 50 free electric charging points in the borough, including two on street points (2).
While the cost of electric cars are high when compared with conventional ones, large savings can be made through the operating costs (about 1p per mile), free or reduced rate parking offers, vehicle excise duty exemption and for driving in London, a Congestion Charge discount. However the battery is not cheap and after a while, its capacity to hold its charge reduces until it becomes unusable and needs replacing. The time this takes depends on the battery technology, how often it is used and how deeply it is charged and discharged. This also raises questions over how these batteries need to be disposed and whether elements can be recycled.
Another question over switching to cars powered by electricity as opposed to liquid fuel is whether our existing grid could cope with this added demand. Forecasts for the timing of peak oil range from now until 2030 (3). This emphasises the immediacy of needing to reduce our reliance on fossil fuels. Therefore, when considering alternative fuels for transport, it must be recognised that while the emissions associated with supplying vehicles with electricity is lower compared to petrol or diesel; our priority should be eliminating our reliance on fossil fuels. Whilst, as highlighted, supplying electricity produced by renewables would eliminate the need for oil, it is going to be many years before renewables can meet transport and other demands of our society. This emphasises the need to reduce the necessity to travel in the first instance.
Speaking of electric vehicles I think this electric car for disabled people is very cool! Environmental and social sustainability in one!
This Kenguru Electric Vehicle is small, mono-seat and environmentally friendly. The maximum speed is 45 km/h and has a 70-110 km of autonomy. And it is incredibly easy to use with a wheelchair: the posterior door opens with a controller and it is possible to get inside with the wheelchair. The car can be driven while sitting on the wheelchair. And it’s a cheaper than converting an electric ‘normal’ car into a disabled-friendly one.