Thursday, July 27, 2006

Seeing the difference: Energy consumption Versus carbon emission

For the last couple of weeks, most part of California is seeing record three digit heat wave. And we hear a lot about global warming and energy consumption. There are continuous preaching to save energy, to switch-off lights, adjust thermostat settings and the like. I see that the media doesn't differentiate enough that energy consumption is not all about carbon emission. There is a big difference between burning fossil fuels on a gas guzzler and setting your A/C to 68. The latter, when done right, will contribute zero to global warming.

Let's refresh some basics:
  1. Earth does not generate energy to heat itself. Sun is the source.
  2. Certain gases are more capable of capturing and storing Sun's energy. E.g. Methane, carbon-di-oxide (CO2), CFCs.
  3. An increase in the amount of CO2, leads to global warming.
  4. Buring fossil-fuels increases CO2 levels.

Some other points related to Energy consumption:
  1. Energy generated using non-fossil fuels or those avoiding buring hydrocarbons (ethanol doesn't fit here), do not increase CO2 level.
  2. Hydro power plants, nuclear plants, Wind/Solar plants do not increase CO2 level.
  3. Coal/natural gas based power plants do increase CO2 levels.

Thus if my A/C receives power from a hydro-electric plant, which let's say captures the power from a dam, there is absolutely no contribution to global warming. Look at the enormous power of a huge waterfall, say Niagara. If I put a turbine down and capture the energy, I in no doubt, increase or decrease the total earth's energy. But when I burn up natural gas to do the same, I increase the CO2 levels. Those increased CO2 retain a lot more energy from the only energy source, the Sun. Thus it contributes to elevated future temperatures.

Thus I feel, we better understand the difference between energy consumption and carbon-emissions. There is nothing wrong and nothing to be ashamed of in consuming more energy. If I don't trap that falling waterfall's energy, it just goes wasted, anyway.

What one needs to do is decrease the producers of CO2 and increase the consumers of CO2. We must use energy source that don't burn up hydro-carbons (sorry ethanol -- at least it is a little better because growing ethanol plant soaks up the CO2 in atmosphere.. so at least there is no net increase in CO2). A way to increase the consumers to conserve forests -- who knows in a distant future we may expend energy (nuclear, say) to soak up the CO2.

I saw Tom Brokaw's recent global warming report in Discovery. I could see only the last few sections.. and it was good to see the term "carbon footprint" being used. But again, they equated the amount of electricity used in home to tons of CO2. There lies the fallacy. Why should the energy I captured from a falling waterfall do anything with CO2? And why that leads any way to increase/decrease of overall earth's temperature?