Wednesday, July 22, 2009

Going Green: Cars


"Biofuels are inefficient and ethically dubious"

From climate change point of view, biofuels are neutral in the long term: if the biomass providing the fuel is grown again, carbon dioxide is going in a circle (from field to car - from car to atmosphere - from atmosphere to field).

Biofuels have quite a lot hanging from their necks. They are mostly produced from farmed plants which can take space from food plants and cause food shortage and undernutrition in the producing country. Fertilizing and machine-assisted agriculture might cause surprising amount of emissions and pollution.

Growing demand of biofuels is creating a need for more fields, destroying tropical forests to make room. Tropical forests are many times more valuable to the ecosystem tham biofuels.

Fuel engine doesn't become any more efficient with biofuel, the engine is wasting 60-75 % of the energy to heat.

More information:

Pros and Cons of Different Biofuels

All Biofuels Are Not the Same

Hydrogen cars and electric cars are very similar: both cars get their motive power from an electric motor. The essential difference is the energy storage. In an electric car the energy is charged straight to the car's batteries, which then release the power to the motor.

For a hydrogen car, hydrogen is produced from water with electric current. Then the hydrogen is turned to electricity in a fuel cell. The electricity then powers the motor. In this process most of the original energy is wasted, only about 20% is available for use. The electric car has three times better efficiency than the hydrogen car.

Hydrogen car is also far from a complete product, experts are talking about 20 years. It's also very expensive compared to electric car, and still depends on distribution and price fluctuations of one fuel.

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