One of the green initiatives of the last decade or so has been “biofuels”.
This involves the burning of wood, in the form of pellets to generate electricity. The process was originally described as “renewable” because although woods and forest were being burnt it was argued that the regeneration of the woodland and forest absorbed CO2.
This sounds a dubious claim as the wood being burnt is of course a store of CO2 that has been built up over many years. We don’t think of forests burning as part of a sustainable solution !
There is an argument that supports “sustainability” if the wood pellets are made from sawdust and waste wood products.
However a BBC Panorama programme a few weeks ago observed that millions of tons of these wood pellets are produced from mature woods and forests in British Columbia and transported 11,000 miles to the Drax power station in Yorkshire. An area of mature wood and forest about 30 square kilometres (about two Savernake Forests!) is being devastated every year to feed our so-called “green” power station of Drax.
Drax gets almost a billion pounds a year in subsidies from electricity consumers in the UK.
Drax only produces ⅔ of the electricity with wood pellets that it produced when it was a coal fired station.
Another “green” initiative from several decades ago was the drive to get people to switch to diesel cars instead of petrol.
The rationale for this is that diesel has much better fuel consumption than petrol (a diesel engine operates at a higher temperature and therefore is a more efficient heat engine) and so produces less CO2 than a comparable petrol engine.
However as any diesel car owner could have told there are a lot more fumes and particulates from diesel. The fumes from diesel include dangerous and poisonous nitrous oxides.
The authorities encouraged the drive to diesel by less tax on the cars and less on the fuel.
There was a massive backtracking on the diesel car and they have now been demonised.
The lesson to be learnt from these two fiascos is to study the technology carefully and not be led into decisions by simplistic sloganising.