Solar pv may be on the threshold of being able to compete with carbon fuels. A report in last Monday's respected UK Daily Telegraph, [ Money section, google UK Daily Telegraph; search; solar ] was that CIGS cells [ CuInGaSe ], printed on foil, are set to come down below US $1 / Watt by 2009, putting them level par with conventional generation capital costs. Anil Sethi, CEO of Swiss corp 'Flisom' says he "don't need subsidies" he "just wants governments to get outa the way!" I second that! There may well be not enough roof area to support cells for 100% solar, as Steve says, but any mass development will hurt Pocos, shaving margins in the middle of the day, just when they earn most money and pv effectiveness is highest, which I surmise will knock on the head them paying for reverse metering your excess!

The price of corn, or indeed any crop producing oil, has shot up because of alternate use of agricultural products for fuels. Whole Grain burners, [ corn, wheat etc.] are now freely available for heating. Converting vegetable oil to biodiesel is a thiving UK/US/OZ/EU backyard industry - basically all you need is a set of scales, a jug, methanol, 'Drano' [hydoxide] and some 5 gallon HDPE drums. Using free waste oil [WVO] from burger joints is very attractive too, if a bit extra work filtering the crud. [Google WVO.]
I'm just starting to build a waste-oil central heating burner, having returned from the UK with all the necessary kit - hopefully more shortly; but a taster is I'm going to filter using a centrifuge, with electric oil pre-heat, a [commercial not home-made] electrically operated nozzle heater and electrical fire safety equipment, having taken on Iwire's advise, thanks Bob- two heads are better than one - even if they are sheeps' heads, as my old Pa used to say! [Linked Image]

Alan

Wood work but can't!