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Man – the swimming pool was cold today.  Just three days with no sunshine is enough to send it back into penguin territory.

Anyway, that’s not today’s entry. I’ve just been at a very interesting seminar by Bill Redman-White, a visitor to the university from The University of Southampton and NXP Semiconductors UK. He was talking about how semiconductor technology (microprocessors and the like) can play a significant part in  tackling climate change.

The general thrust of the talk was not so much  the development of new technology, though that will happen, but taking existing technology and using it more carefully (using microprocessors etc) so that it consumes less energy. There is a lot of industry drive to do this. To some extent, this has been stimulated by legislation in places like California – which dictates amongst other things how much energy your mobile phone charger is allowed to waste when you’ve finished charging the phone but still have the charger plugged into the wall.

Take silicon solar cells as an example. To get the best out of your solar array installation on your roof (by which I mean get the most power out), you need to continually adjust the output load characteristics. The optimum voltage and current, for maximising power output, depends on solar irradiance and temperature, which constantly change. Already, an installation had a dynamic controller on the installation as a whole, but what it doesn’t do is look at each little panel individually. Each panel can experience different characteristics – is a tree’s shadow falling on it?- is your cat asleep on it?- is it covered in leaves? – and a really smart controller can adjust the load characteristics so that each cell is putting out its maximum possible power no matter what its circumstances are. That’s taking the same solar cells, but using them more smartly.

 Another example are the fluorescent light bulbs that are now ubiquitous in homes. They make a big energy (and cost) saving over the old incandescent bulbs, but, only if they have a long life. The key to making a fluorescent bulb last a long time is to get the tube hot before it is ignited. And the smarter light bulbs now have electronics inside them that ensure this happens. (There is a bit of a problem here though – the electronics resides ABOVE the tube (when the bulb is installed) which means that the electronics gets hot, due to the hot air around the tube rising.  Some components really don’t like this – and there needs to be some thought in the design here.)

Bill also talked about hybrid cars, LCD televisions, computer power supplies, etc.  He ended with a good reason for someone to become a physicist or an electronics engineer: the first step to saving energy is to understand what the problems are – that means science and engineering.