A "trailblazing" Norfolk town has begun heating many of its buildings - including the schools - by burning oil made from melted-down cow and pig carcasses. The strategy is described as "equal or lower in carbon footprint than natural gas".

News of the 12-month biofuelled heating trial comes courtesy of the University of East Anglia (UEA), whose Low Carbon Innovation Centre was instrumental in setting up the plan. Though this plan is actually lower carbon rather than low as such.

“This is a major initiative in developing lower-carbon heating options for millions of properties, especially in rural areas, which depend on oil-fired heating,” said UEA's Dr Bruce Tofield.

According to the UEA, 2m British homes have no access to gas for heating or cooking, and so mostly use fuel oil. Heating oil tends to be mixed mostly from the heavier, yuckier fractions of crude oil and produces more carbon emissions than using relatively light and clean natural gas.

The replacement fuel now warming the children of Reepham in Norfolk is, as is normal with biofuels, partly mixed with ordinary fossil fuel. The biologically-sourced portion is made from used cooking oil and from tallow, which in turn is made by rendering down fatty remains from slaughtered livestock. Strictly speaking, tallow is from cattle and lard is from pigs, but industry cares more about things like melting point. The oil now being burned in Reepham's boilers may have started out originally as any sort of animal.

The proponents of tallow-based fuel admit that raising livestock in order to burn their corpses for energy would be a very carbon-intensive way of making biofuel. Rearing cattle or pigs involves the emission of lots of greenhouse gases. But that's not the idea: rather, the thinking goes, people will raise livestock anyway in order to eat it. Thus it makes sense to use the waste products for energy.

If you can ignore the carbon footprint of making the animals and their fat in the first place - which is 80 per cent of tallow biofuel's overall footprint* - the stuff becomes quite green, easily beating biofuel made from primary crops such as rapeseed oil or whatever. The gas, transport fuel and electricity used in rendering, moving and processing afterwards is comparatively insignificant.

It's never going to be a solution for everyone, supplies of animal carcasses being finite (normally, anyway: there was apparently a big boom in renewables certificates after the huge stockpiles of tallow from the BSE crisis mass slaughter campaign were cleared for use). The same goes for used cooking oil. But it's better than simply burning heavy fossil fuel oil, according to the theory.

The Reepham schoolchildren are apparently all in favour.

"The children are enthusiastic about cutting carbon emissions and we have energy monitors for each class," says Lisa Cook, head teacher at Reepham Primary School. "They are genuinely thrilled to be taking part in such a significant experiment."

But has anyone told them what it all means for the piggies, cows and baa-lambs? The whole idea does seem to lead to one unconsidered ethical debate: that of vegetarian/veganism. If you aren't willing to eat meat, are you willing to live in a house or send your nippers to a school heated by burning slaughtered animal corpses? Surely this would be unacceptable to a hardline vegan, if not to the leather-shoe-wearing brand of veggie.

Schools are required nowadays to offer vegetarian menu options, after all. Should they also be required to offer veggie heating? ®

Bootnote

*You can download amazingly complicated details from the Technical University of Graz - tech partner to Reepham's biofuel manufacturer, Argent Energy - here (pdf).