Sustainable Energy – Without the Hot Air - David JC MacKay

    
          Ebook Size : 13.9 MB

          Download :  Sustainable Energy – Without the Hot Air

Everyone says getting off fossil fuels is important, and we’re all encouraged to “make a difference,” but many of the things that allegedly make a difference  don’t add up. Twaddle emissions are high at the moment because people get  emotional (for example about wind farms or nuclear power) and no-one talks about numbers. Or if they do mention numbers, they select them to sound big, to make an impression, and to score points in arguments, rather than to aid thoughtful discussion.

This is a straight-talking book about the numbers. The aim is to guide the reader around the claptrap to actions that really make a difference and to policies that add up.

if everyone does a little, we’ll achieve only a little.

So, if humanity succeeds in doubling or tripling CO 2 concentrations (which is  where we are certainly heading, under business as usual), what happens? Here, there is a lot of uncertainty. Climate science is difficult. The climate is a complex, twitchy beast, and exactly how much warming CO 2 - doubling would produce is uncertain. The consensus of the best climate models seems to be that doubling the CO 2 concentration would have roughly the same effect as increasing the intensity of the sun by 2%, and would bump up the global mean temperature by something like 3◦C. This would be what historians call a Bad Thing.

I won’t recite the whole litany of probable drastic effects, as I am sure you’ve heard it before. The litany begins “the Greenland icecap would gradually melt, and, over a period of a few 100 years, sea-level would rise by about 7 metres.” The brunt of the litany falls on future generations. Such temperatures have not been seen on earth for at least 100 000 years, and it’s conceivable that the ecosystem would be so significantly altered that the earth would stop supplying some of the goods and services that we currently take for granted.