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Peter J Moss
Tuesday 8th May 2012: Green transport - comparing petrol and diesel vehicles with their electric and hybrid rivals
Many of the earliest motors cars were electric and quick for their time, around 30 miles per hour! There were petrol-electric cars too: however as Internal Combustion Engines became more effective they displaced the already established electric propulsion systems. For several decades petrol engines held sway. Diesel engines were introduced first to trucks and more recently to cars. So why did these ICEs take over and dominate road vehicle propulsion?
The power required to propel vehicles is influenced by tyre and aerodynamic resistance as well as climbing hills - roads are practically never level. Generally the power required is a function of vehicle size and speed, but varies considerably with different vehicle use and driver 'enthusiasm'.
A vehicle range of at least 500 miles is expected of modern cars while the desired performance (top speed and acceleration) requires quite a high maximum power - readily available from petrol and diesel ICEs. Matching this with electric alternatives presents numerous problems - especially if we want all of them together.
Concern about 'CO2' and global warming has triggered a renewed interest in electric propulsion - perhaps for the wrong reason, that it is pollution free! However, along with recent advances in 'power electronics' that enables much more effective electric management of batteries and motors, as well as new battery and motor design - new hope is in the air.
Long distance road vehicles are unlikely to ever be all-electric: in-town all-electric cars are already available and quite effective. What will be the future these and the hybrids which promise so much?
Come along and join us at 7:30pm at Science Oxford Live, 1-5 London Place, St Clement's, Oxford.
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