Sustainable Energy – Without hot air
Global warming problem is HUGE, our need for energy is HUGE, but how do we balance one huge with another huge? Essentially this is the point David MacKay try to tackle in his book "Sustainable energy- without the hot air" and I must say he paints a rather grim future regarding our ability to meet energy demand using renewable energy. Considering we hear news about icebergs breaking, or bizzare weathers happening around the world, it seem like a pretty important issue but everyone seem to either hold a skeptical view toward climate change, or are too busy to think about it seriously. And even though many politicians claim to be getting "serious" about combating climate change, because of Mackay's book, to me, it seem like goal of replacing fossil fuel with renewables is unlikely to be achieved in near or distant future... the implication is both unimaginable and unthinkable...
One of his main conclusion is whichever method(s) we use to replace fossil fuel (wind farm, hydro, plant, tidal, or solar but not nuclear because it's not renewable), it all require country sized space to be physically practical. For example, build wind farms twice the size of Wales, solar panels the size of Germany + in desert places, grow plants twice the size of Britain and so on. In another word, he is saying it is practically+ physically not workable (unless we can turn most of land space into energy production) that we will meet our energy demands from renewable source. More importantly, this conclusion is drawn based on physical considerations only. Other considerations like the economic consideration of cost or political consideration like "you can build it anywhere except for my backyard" will shift any renewable solution from improbable, to impossible.
Nice thing about Mackay's book is that unlike many climate change debates we hear. His argument is based on numbers which tells you without dispute (except for how the numbers are derived) whether we have reason to be concerned. The following passage illustrates the motivtion for his book
"This heated debate is fundamentally about numbers. How much energy
could each source deliver, at what economic and social cost, and with
what risks? But actual numbers are rarely mentioned. In public debates,
people just say "Nuclear is a money pit" or "We have a huge amount of
wave and wind." The trouble with this sort of language is that it's not
sufficient to know that something is huge: we need to know how the one
"huge" compares with another "huge"? namely our huge energy consumption.
To make this comparison, we need numbers, not adjectives." (Mackay 2008, p3)
David MacKay's book Sustainable energy - without the hot air is freely available from his website http://www.withouthotair.com, or it can be purchased from amazon.co.uk. You can also listen to his light hearted talk to understand his ideas (talk (mp3) here (25mb) + ppt(pdf) here (27mb)). Oh ! and it is really fun to listen because he is a really funny man :P