The Cambridge Energy Forum organised a day-conference on Sustainable Energy – 1 Dec.2006. Sadly I had a program meeting in the morning and children to pick up after school so I only got to go to bits of it: which was: Mr Karl Carter Director of Operations, British Sugar and Biofuels; and Professor Trevor J T Whittaker Professor of Coastal Engineering Queen’s, University of Belfast on Tide, Wave and Offshore Wind.
Biofuels from British Sugar: what I remember was: will only account for maybe 10% at very most, due to the land required and needs to be done properly to get any kind of CO2 payback. Which means just turning stuff into bioethanol using imported electricity and gas has virtually no gain (this is whats done in the States, apparently mostly as farm support). To get a decent payback (including transport and fertiliser) requires CHP and strawburning plants. Factoid I didn’t know: adding 5% ethanol to petrol improves the octane rating; which allows you to add slightly cheaper petrol; adding more than 5% is a problem because the energy density goes down. By happy coincidence the EU is due for 5% within a few years. He was unkeen on oil-based plants (oilseed rape, etc) since strach-based apparently gives you about 2* as much output; making this stuff reasonably competitive will need using more of the biomass. The economics of this all were rather unclear (he talked more in terms of CO2 payback than money) and I’m guessing its only viable with subsidies. Apart from anything else, ethanol cheap enough to replace petrol is cheap enough to replace vodka…
Tide, Wave and Offshore wind was sort of more fun; in that it had exciting engineering in it (by contrast biofuels didn’t show any details of the conversion; either its too dull or too secret). Amusing titbit: increasing oil prices should be great for its financial viability: but: all the jackable barges, which are needed to install these things, are off earning money exploring marginal oilfields because the oil price is high… Apart from that: the bottom line was that its non-mature stuff, not really competitive on cost at the moment. There is a nice wave-powered station in the Orkneys; but it requires nuclear-bunker levels of concrete (which costs; CO2 and money) in order to survive being pounded by the waves.
Then I had to rush off to pick up the kids…