Some of my confrères in the alternative energy business will tell you that the high oil price is a great thing for the industry. Of course, they're largely right. If the oil price had instead fallen from $10 per barrel to $2 today from 1999, I doubt this and many other websites would exist. No question, higher oil prices do mean people do tend to look more closely at what the alternatives are and whether they can save money using them. Although we should not overlook completely that the oil business is even more motivated to keep drilling because in the face of excess demand and limited supply, the margins have never been higher.

Yet there's another much darker consequence of unaffordable energy - increased criminal temptation and activity. Which brings me the most novel alternative energy story of the week. Apparently, in the UK, the price of used cooking oil has risen 10 times in the last 5 years to £550 per tonne. That's because make your own biodiesel kits - see here - are increasingly available and making it cheap to run your vehicle on used cooking oil. Time was when restaurants couldn't even give the grease away. No more. In fact, now restaurants and fast food joints are having their used cooking oil drums stolen from them !

There just isn't enough used cooking oil to go around and to recoup the investment on your £1000 home biodiesel kit, you would presumably need quite a lot of the stuff. Added to that the reforming zeal of various green-minded middle-class campaigners railing and largely getting their way against blue collar fast food chains and you get a classic and complicated unintended consequence from oil at over $140 per barrel - increased waste and CO2 emissions !