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CLEAN GREEN DRIVING MACHINES
This week we have a special Science in Action as part of the Climate Connection season, which has been made in association with the Open University who are launching a ten year diary on environmental change.

Since the industrial revolution, global growth and development have been linked with the combustion of fossil fuels and the release of greater and greater amounts of carbon dioxide into the atmosphere. As world powers meet in Copenhagen to discuss measures to help combat climate change some scientists and activists are saying we need a new, technological approach.

The average car travels about twenty thousand kilometres a year according to the US Environmental Protection Agency. It burns fossil fuels in the form of petrol or diesel, and releases over 5000 kilograms of carbon dioxide.

Transportation is the fastest-growing source of U.S. green house gases. Jon Stewart investigates the American love for the motor car and can this car mad nation really be weaned off the motor vehicle?

Detroit may be the birthplace of the car, but Los Angeles is where it’s really taken residence; a city on rubber, as it's known. Jon Stewart visits the city's iconic annual auto show and finds that manufacturers are jumping on the clean green band wagon and are actually delivering top spec environmentally kinder cars.

EFFICIENT ENGINES
Electric cars are all well and good but they are still some way off becoming popular with the public. Jon Stewart looks at short term alternatives. At the Mechanical Engineering Department at Stanford University near San Francisco they are developing much cleaner traditional engines.

CLEAN ENERGY
Another statistic from the America's Environmental Protection Agency – the process of generating electricity is the single largest source of carbon dioxide emissions in the United States - accounting for 41% of total CO2 emissions.

The introduction of electric cars, requiring overnight charging, will mean that figure will increase dramatically unless we could meet all our energy needs from solar power.

That's the promise of schemes such as DESERTEC – a proposal to install a vast solar farm in the Sahara desert in Northern Africa and then sell that clean energy to Europe. An ambitious, and arguably contentious scheme – but when you consider that less than 1% of the Earth's deserts could supply the whole world’s electricity needs – it's one that has great potential. Neil Crumpton an energy campaigner for the environmental group Friends of the Earth and a member of the DESERTEC Foundation explains the concept.

But what about harvesting the sun's energy all the time? Science in Action talks to John Mankins, the president of the Space Power Association. He thinks a better alternative is to put solar panels in space, above any cloud cover, in intense sunlight and then beam that power back down to earth.

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