05 Feb 2010
Yes it's the latest bright idea from "Techno-Crassy ". Why eat food or feed it to pets or Pigs (for instance) when - with only a moderate investment in our huge machine - you can burn it. Super !
Also you can get little windmills to stick on the top of your market which you tell everyone is running the lights and freezers. We're all pretty stupid, why worry about it ?
08 Feb 2010
And will they be digesting food that is perfectly good but at it's sell by date when it could be used for human consumption? It would be much greener to arrange things so as not to generate so much food waste in the first place!
08 Feb 2010
Sorry to pour cold water on your scepticism. Anaerobic digestion offers a number of benefits including renewable energy and stabilised fertiliser. Digesters are relatively small and can be located close to the site of waste arisings helping reduce transportation costs. Small generation facilities help to strengthen electricity grids and reduce electricity transportation losses associated with moving power from massive centralised power plants. With full combined heat and power the energy efficiency of digestion plants can reach 90%.
The fact is that for many years waste food has been landfilled, where yes it anaerobically digests. If it’s not captured it is released into the atmosphere where the methane is far more polluting than carbon dioxide. Food is wasted in great quantities across the globe and especially here in the UK. Yes, the focus should be on reducing waste and not disposing of perfectly eatable material. However some waste food is unpreventable - think peelings, banana skins, fats and wastes from processing foods. Also, like it or not a good proportion of food goes off before use. Have you never thrown out food from your fridge or freezer you could have eaten?
The alternatives to anaerobic digestion are landfill, incineration and gasification. Incineration or gasification of food waste is not a logical approach with regards to energy. A large amount of the energy is input simply to evaporate the water content of the food waste.
If we look at where most of our electricity comes from - finite stores of fossilised plant and animal matter, large amounts of which are held by dubious governments we cannot rely on, that we simply dig up. Extraction costs of this material will rise as they run out. Whether or not global warming is happening we cannot carry on burning this material inefficiently and taking it for granted.
Wake up and look at the big picture. Global society cannot go on the way it has been for the last century.