Food to Energy Plants: A Load of Pig Swill?

Image credit: Prospect Magazine

We all know that waste food is a problem, but luckily there are plenty of solutions. Grocery stores are turning food waste into electricity, and Stockholm is even embracing garbage disposals to collect biogas. But is there a better way? Could it be that there's a greener alternative for using up unwanted food? The obvious answer is, of course, to eat it. Author and activist Tristram Stuart has already revealed the insane amount of food waste in the industrial system, and we know that there are freegans and dumpster divers eating well across the Globe. But how do we step up such efforts to reclaim food waste? Isn't food-to-energy a sensible way to use up food that not even the dumpster divers will touch?

Maybe, and maybe not. At least, so says the very same Tristram Stuart mentioned above. In an article on food to energy in Prospect Magazine, Tristram visits a pioneering anaerobic digestion plant in the West of England. He notes that the plant can convert a tonne of food waste into 255kWh of electricity, offsetting 110kg of carbon-dioxide emissions compared to conventional sources. Better yet, the byproduct is a nutrient-rich liquid effluent and a peat-like compost which farmers use on nearby fields. And as if that weren't enough, the whole process is diverting organic waste from landfill that would otherwise produce methane - an extremely potent greenhouse gas. So what's not to like?

Tristram points out that the only reason the process is currently viable is heavy taxes on waste going to landfill and generous government subsidies. That, in itself, is no bad thing - paying for dumping trash, and offering support to services that benefit society seems to me like what Government was put here to do. (Oh, that and providing free health care...)

But if we're going to provide support to such industries, then we should at least provide a level playing field for alternatives. And that's where pig swill comes in. Given that waste to energy plants recover only 0.75 per cent of the energy it takes to grow the food, it might make sense to look at using food as, errm, food. Sadly, feeding sterilized waste food to pigs is banned under European law. (What was I saying about the role of Government?) This despite the fact that heat treated bread, vegetable and dairy waste has been shown to be perfectly safe as animal feed, and the Japanese and South Korean Governments even subsidise the process.

And don't even get me started on reducing the amount of waste in the first place. According to Tristram, not one UK supermarket has yet to set targets for reducing food waste in their supply chain. So by all means, turn waste food into energy - but let's look at what food really is "waste" before we do.

Tags: Agriculture | Alternative Energy | Dumpster Diving | United Kingdom | Zero Waste

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