Thursday 12 April 2012

It's not easy being green

Just a quick catch-up on a couple of recent blog posts....

Back in early March I posted a little piece about our local council's plan to turn off the street lights at night in order to save money and (yawn) carbon emissions.  Update as of last night: on our street, the lights are still on!  The local paper reports this week that the scheme has been put on hold because of a fault with the light sensors specially installed as part of this project.  These had apparently begun to turn the lights off at random in other parts of the county, to the reported bafflement of the council's engineers.  It now appears that all 40,000 sensors (one per streetlight) may be faulty, and that replacing them -- which we are assured will not be at taxpayers' expense -- could take almost a year!

Lots of interesting questions here!  First, just how much has this scheme cost, anyway?  And if buying and installing 40,000 photo-sensitive cells cost anything like as much as I suspect they do, can we really believe assurances that the council is prepared to cancel the scheme after a couple of years if the citizens don't like it? Who was responsible for hiring the company that provided the sensors?  Apparently the "fault" is that the software couldn't handle the switch to British Summer Time a couple of weeks ago. Hello??  And lastly, given that the lights are supposed to switch off at midnight, when it's dark at all times of the year, just what purpose do the light sensors serve?  I'm no physicist, but I suspect we may not be getting the whole truth here.  

Now on to a more recent posting -- just this week, in fact, when I wrote about energy from waste (EFW) in the context of the UK's dwindling options for keeping the lights on.  The Times, which ran the original story about mounting local opposition to waste incineration, has been inundated with letters dissing the technology. (Original article and correspondence all paywall protected).  Interestingly, many of the letters say that fuddy duddy, old style incineration has now given way to a much superior alternative: pyrolysis.

Now, as I said a moment ago, I'm no physicist, but I am a one-time classicist, and I'm confident that the Greek root of the term pyrolysis means "fire".  (Same root as the word "pyromaniac"). A quick search on Google shows that pyrolysis is in fact....burning in a low-oxygen environment!  It's how charcoal has been  made for aeons. Companies that sell the equipment you need describe it as a "furnace", which gives you some sort of a clue as to what's involved.

So: old-style EFW and pyrolysis -- a distinction without a difference? Not necessarily. It does appear that pyrolysis plants are easier to build, and that there is a lot less residue to dispose of at the end of the process.  Even so, this is really just a more advanced version of rubbish burning, and as such it's unlikely to be well received by the NIMBYs,  who don't want trucks of rubbish trundling through their neighbourhoods (unless, that is, they're carting it to somebody else's neighbourhood).

It's also unlikely to appease the greens.  Here is a good overview of pyrolysis from the Friends of the Earth website. They're still mostly opposed to it, mainly on the largely unproven basis that pyrolysis, like incineration, reduces the pressure to recycle. I'm sure you know the old saying that "the best is the enemy of the good". Incineration and pyrolysis both look like good solutions to a mounting problem.  If the NIMBYs and the greens combine to stop us from implementing either one, it's inevitable we'll just keep sending the waste to landfill. At least the rats and the seagulls will be happy.


No comments: