May 2006

Being Greener A to B

Worried about the impact of your car fuel? What's the alternative?

Liquid Gas

Liquified Petroleum Gas (LPG) is the most widely available alternative to petrol. LPG is a bi-product of petrol which was treated as a waste for many years by oil companies and flared off. Whilst this is a fossil fuel, it has been endorsed by UK Government due to it’s low carbon emissions.

1,400 UK petrol stations now sell LPG and a number of car-makers, including Toyota, have launched LPG vehicles in this country. "Bi-fuel" models able to run on LPG or petrol are also now available, or you can pay around £500 to have your petrol engine converted to run on LPG.

Whilst LPG produces lower carbon emissions than petrol, its emissions still exceed those of "greener" fuels, and recent Government plans to set future fuel duty to reflect fuels' impact on the environment have prompted car-makers to switch their attentions elsewhere. Most people choose LPG it because of its cost and it is popular in countries like Poland and Turkey.

Grains & Vegetable Oils

Bioethanol and biodiesel are green fuels made from grain, rapeseed and vegetable oils. They produce significantly fewer greenhouse-gas emissions than petrol and are regarded as almost carbon neutral as carbon emissions during production and consumption are almost equal to the amount removed when the crops from which they're made are grown.

E85 - a mix of 85 per cent bioethanol and 15 per cent petrol - is already available in parts of the UK, including Somerset. A pilot scheme was recently launched in Shropshire, where seven independent petrol stations now sell B5 biodiesel produced from rapeseed or vegetable oil. Ordinary cars are capable of running on a mix of 95 per cent petrol and 5 per cent bioethanol or biodiesel, without any modifications. To move beyond 5 per cent, however, an engine must be modified, which essentially means replacing rubber seals and aluminium parts with materials not eroded by bioethanol.

Bioethanol is currently more expensive than petrol because of the cost of producing and distributing it. There is also the theory that as most petrol stations are owned and operated by the oil industry, they have little interest in selling it. Another concern is whether there is enough grain, rapeseed and vegetable oil to produce the volumes of bioethanol and bio-diesel needed to make these green fuels a viable alternative to petrol. Despite this, a number of supermarket petrol stations now sell petrol containing 5 per cent bioethanol as standard - a practice expected to spread as the Government works to meet its 2010 renewable-fuel target.

Organic Waste

Decomposition of organic matter releases methane and when burned, it releases up to 25 per cent less carbon dioxide than the combustion of the same mass of coal, with no emissions of nitrogen and sulfur oxides. Scientists are currently exploring ways of converting methane into fuel for use in transport.

Nowhere in the UK, yet. However, car designer Christopher Maltin, the British pioneer of unleaded petrol, has developed a system to convert organic waste into fuel, and recently showcased a car powered by manure which pumps out only water and carbon dioxide. In Sweden, a number of passenger trains now run on methane extracted from the entrails of dead cows slaughtered for food.

To be used efficiently, biogas needs to be used in close proximity to where it has been generated, as moving it long distances is costly both in economic and environmental terms.

Electric

These are cars fully powered by mains electricity.

A small number of electric cars are now on the market, including the G-Wiz - a two-door hatchback created by the Reva Electric Car Company. Motorists are being offered free parking in Westminster and the City of London, and a congestion charge waiver, as an incentive to buy electric vehicles. Also, ‘green’ developments sprouting up all over the country are integrating electric charging points into their design.

The drawback is thatfully electric cars cost almost twice as much to buy as standard vehicles. And although they produce no emissions they're only as really as environmentally friendly as the electricity used to power them. Furthermore, they are designed to run shorted distances (shorter than 50 miles). "Arguably, their biggest limitation is their range [typically, they run out of juice after 50 miles. A new generation of electric cars is in the pipeline with Nissan and Mitsubishi due to launch models in the near future.

Hybrid

Hybrids are powered by a combination of electricity and petrol. Car-makers claim they are greener than standard vehicles because an integrated electric motor helps the engine by boosting it during acceleration, improving fuel economy. The electric motor also runs the car when stationary to minimise emissions, and the battery that powers this motor charges itself up with energy recovered during deceleration.

The Toyota Prius and the Honda Civic are two of the best-known hybrids currently on the road. BMW, Peugeot and Citroën also have comprehensive development programmes for hybrid electric and petrol, and electric and diesel, cars.

The initial purchase cost of hybrid vehicles is comparatively high and many experts question just how efficient hybrids really are- with a recent consumer study revealing that the UKs bestselling hybrid the Prius, only averaged 45-50mpg compared with the official figure of 66mpg.

Diesel hybrids are even cleaner and more efficient than gas hybrids. But they are also that much more expensive. This type of vehicle, however, is still in development.

Hydrogen

Hydrogen-powered vehicles typically run on a fuel cell in which hydrogen mixes with oxygen to produce water - a process that creates electricity, which in turn powers an electric motor. Although water vapour is the only emission, how the hydrogen is made in the first place is a more realistic indicator of whether hydrogen can be called a truly green fuel. Hydrogen can be made in a number of different ways including electrolysis - the splitting of water into hydrogen and oxygen. It is then cooled to turn it into liquid hydrogen, which is distributed in pressurised cylinders.

Honda is one of a number of car-makers developing hydrogen-fuelled vehicles. Its FCX model is currently being piloted in Japan and the US, where the Spallino family of Redondo Beach, California recently took delivery of the first hydrogen-powered fuel cell car in private use. Closer to home, a two-year project in London involving single-decker buses powered by hydrogen fuel cells recently ended.

People to wait a while before they can actually purchase one of these vehicles and purchase cost will be high. Furthermore, investment by car-makers will be limited due to a lack of established infrastructure to distribute hydrogen fuel,

Steam

Typically, a much of the energy released when petrol is burnt is lost through a car's exhaust system as heat. The BMW Turbosteamer proposes to cut the amount of energy lost by 80 per cent, by ensuring energy from exhaust gases is used to power a steam engine which in turn powers the car.

The technology is still at the test stage. However, the plan is that eventually the Turbosteamer could be fitted to all BMW models- this is still a petrol fuelled car however.

Solar

Car makers have been experimenting with solar power for a number of years. In 1993 the Honda Dream won the World Solar Challenge, crossing from Darwin to Adelaide using only the power of the sun. Today, manufacturers are continuing to look at ways of incorporating solar panels into car design.

Again, this is not available yet but Ford’s plans for the new Reflex include solar-powered headlights.

It is likely that solar power will be used in conjunction with other alternatives rather than as a stand-alone.

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