Wednesday 26 October 2011

Energy From Waste

In my last blog I called for more effort on energy from wastes. I showed some nice pictures of Anaerobic Digester Plant in the Czech Republic. Who listens? Not many, I was not bold enough in my delivery..

So lets show what wastes we are talking about:

This is where London sends at least 50% of their DOMESTIC wastes
 London is a great example. It generated hundreds and thousands of tons per year of domestic waste plus a further 16 million tons of commercial wastes (including construction materials). No, that is a lot of stuff.

But most of it is transported out of London! The total bill each year for collecting and redistributing (I cannot use the word recycling as this does little which could truly be considered recycling) is £580m. At the same time they run 10,000 buses on diesel choking up the hard pressed residents. It's utter madness. It smacks of blinkered, too specialised, compartmentalised thinking. We need some generalists who can co-ordinate - to pull together all these strands; and to bang a few heads together.
A Mountain to "Recycle"

Luckily Boris Johnson has a plan. And its not too bad; so long as the plan is carried out and not just started as a publicity stunt (as if....). He has begun to listen to what a great deal of people in the UK already know. However all this is put into practice on the Continent already and has been for decades.

In Germany they reckon that they could replace all their natural gas needs from bio-gas, or bio-methane. This would be generated from 'digesters' which would process farming wastes, food industry wastes and sewage works to make gas. In fact they already do a huge amount.

And the best thing is that they generate gas, which they can easily store - unlike electricity. This is a great point worth making. All the detractors regarding renewables always complain about the [assumed] storage problems with all technologies. Well with bio-methane we can store the energy for plenty of things.

If properly designed sewage can be big exporters of bio methane
Like using the stored bio-methane to run Buses (as they do in Sweden), Lorries and Cars and even trains. The bio-methane can also be used to generate electricity on demand -just so long as we can find a usage for the heat that this process generates (something that is rarely done in the UK's conventional power thinking).

Food Wastes can make useful bio-methane
Lastly bio-methane can be injected into the gas grid, like our partners have done in Didcot, Oxfordshire with Thames Waters Sewage Works there. When it goes in we get 'Green Gas Certificates', and users can buy it out at their end, so we can effectively utilise the existing gas grid to distribute all the bio-methane generated from anywhwere in the UK within a sensible distance from a gas main (for which we have the UK's plans). Just like the renewable electricity schemes. But unlike electrcity, as I have said it can be stored and used when needed. In fact it has to be stored, because there are times when the gas grid is not ready to receive the bio-methane.

Our' love affair' with waste is institutionally inefficient. Very little of what happens today makes much economic sense. Sending stuff to landfill is not necessarily good. But not capping off the gas generated by this same landfill is [energy wise] criminal. The gas needs to be 'harvested', and ideally injected into the grid. Transporting wastes out of London is pretty stupid too, all that energy expended to move waste around - it's well ...wasteful.

All those crisp clean tanks from my last blog could be dotted all around the less attractive parts of London, to generate gas on the spot, from food wastes from all those eating places. In turn that gas could make electricity, heat or transport fuel.

It just needs vision and a generalist thinker. Like me.