Energy

[contains rather more scientific discussion than humour]

It strikes me that apart from an algebraic solution to the second velociraptors question the most pressing problem for the scientists of our generation is bulk energy storage. We are going to end up harvesting energy from the sun, wind, tides, and controlled nuclear reactions, but we don't know where to keep it. For the national grid it's quite easy, you just pump water up hill on sunny/windy/tidy/fissiony days and let it come back down (through a turbine) when you want to make some electricity.

It's much harder for automotive transport, and quite frankly batteries are so poor in terms of energy density, mass, cost, and longevity compared with fossil fuels that it's laughable. I once asked a friend of mine who has much more chemistry than me, and a background in automotive engineering "If we had huge amounts of hydroelectricity, could we crack water and atmospheric C02 and synthesize liquid hydrocarbons?" I've never really understood his answer which was "Let's have lunch first shall we?"

My new idea is that cars should burn aluminium. You might think that aluminium doesn't burn, and it certainly doesn't if you just hold a fag lighter up to a bit of kitchen foil, but as a fine powder at a high enough temperature it's incredibly energetic. There's a thing called the thermite reaction, and the most exciting example is a solid rocket propellant called ALICE, it's simply aluminium powder and water ice. It burns hot enough to crack the water and the aluminium steals the oxygen from the hydrogen.

I see a future where we buy sacks of aluminium powder at the garage, and empty our exhaust hoppers into a pit of aluminium oxide which gets sent back to the refinery for the energy intensive process of turning it back into metallic aluminium.

Richard "I don't know enough chemistry to know why this wont work" B