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Comment Re:Only 30 Grand? (Score 3, Insightful) 426

Even if the answer is a giant coal power plant, that coal power plant is much more thermally efficient than your Golf TDi. The cold TDi's engine is around 34% efficient (and that's ignoring the fact that a petrol car has a much more significant gear box and transmission than an electric, and hence loses more there, it's likely to only about 15% efficient at the wheels). Meanwhile thermal efficiency for power plants is around 60% and electric cars have thermal efficiencies around 80%, so in total about 48% thermally efficient at the wheels. That is, for the same power, an electric car will burn 3 times less fossil fuels, even if you assume that it is 100% powered by fossil fuel power plants.

Comment Re:Stop trying to win this politically (Score 5, Insightful) 786

If Global Warming is a science issue then stop trying to make political arguments.

Global warming is a science issue and is argued by scientists in papers. The problem is that convincing everyone to do something about global warming is a political issue, and politicians aren't above discrediting anyone who opposes them to get their way.

Comment Re:Deja Vu (Score 1) 151

It doesn't need to carry it when it launches though - this is the big benefit. A huge amount of the fuel that rockets carry is for the sole purpose of lifting the fuel and oxydiser for everything after 20km up by 20km. That's when the rocket is heaviest, and when it's having to push through the thickets atmosphere, and when it's travelling slowest (yes, counter intuitively, rockets are more efficient the faster they travel).

By not having to carry the oxygen for 20km onwards at launch time, you reduce the launch weight hugely, and in doing so enormously reduce the amount of fuel needed to lift that launch weight. Add to that that you don't need to carry the oxidiser for that fuel either, and you come in with an absolutely massive weight saving.

You also get a space saving, because the oxygen that you pack in as you fly upwards can be packed into the space that the hydrogen you're burning used to take up. That space saving saves weight in the structure of the vehicle, and it saves aerodynamic drag. That's two more large savings there.

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