Green dogs and green buses

Of course the Guardian has not been able to resist making it into a joke, but it makes perfect sense: San Francisco is planning to use dog faeces to generate energy. The city already recycles 60 per cent of its waste, but plans to further reduce the total by 75 per cent by 2010. Four per cent of the residential waste now is dog faeces, so this is obviously a problem to address.

Sunset Scavenger will place biodegradable bags and what are tastefully called dog-waste carts in a popular San Francisco dog park. The dog poo will then be put into a methane digester, where bacteria will eat away at it for two weeks before it turns into methane gas. The gas can then be used to power appliances such as cookers and heaters that currently run on natural gas. It can also be used to generate electricity.

Of course it is a gift to cartoonists, but it also sounds perfectly sensible to me, particularly having just been down to Regent's Park, where I noticed what someone was complaining about in the local paper - dog-owners who "scoop the poop", then dump the plastic bag on the spot. Of course you couldn't collect all dog faeces, but I'd bet the daily quantity across Regent's Park would be quite significant. And a lot of it already goes into specially designated bins.
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There seems to be some confusion about when it started - according to Green Party sources it is today - but anyway, finally London is getting some (reasonably) green buses, which arehybrids that run a lot of the time on battery power. When running on diesel, they are charging the battery and braking also helps to charge it.