Rugby 2012

After an excellent lunch (but no chocolate in the pudding) I attended a workshop entitled “Spicing up your particle physics teaching” given by Graham Bone, Exeter school. I won’t bore you with what I did but it gave me a lot of good ideas to help me teach my year 13s next year.

The final lecture of the day was entitled “Please Do Not Buy An Electric Car” by Averil MacDonald, University of Reading.

If you buy a Toyota Prius and you benefit from zero road tax and no congestion charge in London. Electric cars are held up as the ideal replacement for petrol and diesel fuelled combustion engine, promising reduced running costs and zero carbon footprint. Cities around the country are seriously considering installing charging points to encourage their citizens to adopt clean technology. But the truth is far more worrying and if we did all buy electric cars it would have a devastating effect on our lives and the economy as a whole. It is not clean technology as it simple moves the pollution elsewhere.

Power stations have to run all day. On a cold day about 60Gwatts of electricity is required in the UK for 6E10 people. This works out as 1kw per person. 1GW would power 400000 kettles (rated at 2.5kW) and produce 1000000 cups of tea. Peak household demand is about 10kW of electricity per hour so over 10 hours this would be 100KW. At the moment we can generate up 75GW of electricity.

Electric car batteries require 85kWh over 10 hours to charge and you get 25 miles for one hour. If we were to replace each of the 32 million cars with electric cars we would need 10 million charging points (and enough space to allow the car to remain in place for 8 hours). The National Grid could not cope with this, complicated by the fact that some power stations will be closed in the next 10 years. One way to get over this is to simply switch electricity off to our houses (would not be popular). We could build more power stations, preferably renewable. We would need 60000 wind turbines; a typical wind farm needs an area of 70 x 70 miles for 125m diameter blades. We could put solar panels on at least half of the roofs in the UK and build 5 new nuclear power stations.

One piece of advice given by Professor MacDonald was not to get a smart meter. They can be used track household behaviour and could be used to switch off electricity to households who are deemed to be using too much electricity (or even terrorists as a way of attacking the country).

Another alternative to our energy needs is to obtain our electricity from other countries. HVDC (High-voltage direct current) appears to be the way forward. For long-distance transmission, HVDC systems may be less expensive and suffer lower electrical losses. For underwater power cables, HVDC avoids the heavy currents required by the cable capacitance (for example NorNed).

This would produce a Super Grid.

Of course we also have to think about reducing our carbon emissions. The cost of doing that globally has been estimated to be £10E13 by 2030.

Professor MacDonald ended her lecture by explaining that in her opinion hydrogen fuel cells was a much better option for powering cars.

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