illuminating science

I went to a great talk on Friday from Prof. Andrew Blakers from Australia National University (ANU), in Canberra. He was talking about their new method for manafacturing solar cells, which makes them very cheap and yet have good efficiency (around 20%, which is apparently about average). The key step was a clever way of slicing up blocks of silicon very thinly and precisely so that they can be layed out onto the solar panel. the cells are also double sided, so if you put a mirror behind them, then light that doesn’t get picked up the first time has a chanced to be used on the way out.

He had some of the solar cells with him - they’re actually flexible! You can bend them (at least to a point ), and they keep working just fine! What was particularly interesting was that in his opinion that the solar cells they’re producing will be economically viable alternatives to fossil fuel for energy production - it will cost less to install a solar panel on your roof than to buy regular electricity. Of course, he was a little hazy on the actual timescale, but something on the order of 10 years seemed reasonable, if I recall correctly. Another interesting point was the “energy payback” time - how long do the cells need to function to have produced more energy than was required to make them - is about 1.5 years, shorter than the average of around 3 to 5 years. This is actually an important measure - in the early days, solar cells took so much energy to make, they would have had to run for 30 years before repaying that energy!

One of Austrlia’s energy companies, Origin Energy, has licensed the technology and is in the process of commercialising it, so hopefully we’ll see Sliver Solar Cells coming to a roof near you!

Also today came an announcement from that company I love so very much, Google, that their headquarters (the Googleplex!) will be installing solar panels to provide about 30% of their office power consumption. Producing 1.6 megawatts, it’s enough electricity to power 1000 homes, and their announcement says they expect it to be a cost saving move. Incidentally, Google is also building a new, huge data centre in Oregon, where numerous dams provide cheap and renewable power. Yet again, kudos to Google for being at the forefront of technology.