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Fusion. The ultimate, clean energy generation potential.

Also, don't discount wind that fast. The typical "it will have to whole country with these 1-2 MW turbines" line of argument is old. Modern offshore turbine designs are 6MW, getting to 10MW by 2012 and 20MW designs are in the works now. Advances in the field have been massive just in under a decade, with higher output efficiency (gearless designs) and less overall maintenance effort.

The trouble with wind is the variability. And even if you assume that there is always good wind somewhere, the energy grid just can't handle shifting power back and forth so quickly.

It takes time for the other generators to change output levels, so during high speed wind turbines tend to get disconnect from the grid because of the harmful effects they have on it.

The net result is that they don't produce out as much energy as expected.

> It takes time for the other generators to change output levels, so during high speed wind turbines tend to get disconnect from the grid because of the harmful effects they have on it.

Traditionally, a wind turbine generator works only in narrow range of speeds (say, 2000 rpm). In older designs the variable speed of wind was addressed by using a (massive) gearbox, not unlike what you have in your car. The newer designs (e.g. what Siemens Windpower is churning out now) are gearless, don't suffer from that problem, and have in ballpark of 40% better energy efficiency.

The cap/penetration effects of wind power on the grid are being studied, but on levels below 1/5th of total consumption it is believed to not cause any substantial problems. Most of the existing grids can accommodate that. I think no country approached the 20% wind power penetration yet.

I forget the name of the company, but some guy is working on electric cars with swappable batteries: the idea is that instead of plugging your car in overnight to “refuel” it, you would take it to a service station and change the discharged batteries for charged ones.

Now imagine that the outlets for charging those batteries were connected to a wind-powered grid, where the power company charged a lower rate in exchange for less reliable availability. That kind of service would suck for running, say, an Internet data center, but it would be adequate to make sure that all the batteries that came in by 6:00 pm were fully charged by 6:00 am.

Voilà! Two problems solving each other.

Most of the big car companies are experimenting with some sort of battery swapping concept. The problem is that they all have to get together and agree on some sort of standard interface, power ratings and dimensions. If a service station has to stock dozens of different models of batteries then the idea has basically failed before it even gets started.

So, energy is hard, let's go shopping?

Yes, we need a smarter grid, we need a breakthrough in battery technology, etc., etc. The way forward is going to be hard and take serious investment in technology, but what else is new?

I would love to see some offshore wind turbines, but as soon as that's brought up the rich people from both the left and right decide they don't want to ruin the views from their beach houses.

It seems like so many people want everyone else to be clean while being dirty themselves.

The “Cape Wind” project saw massive opposition from residents of Nantucket... but they failed to block its approval.

Thorium molten salt reactors are potentially a good option - nuclear that doesn't produce much in the way of dangerous byproducts, and can't melt down. China's investing quite heavily in them iirc.

Those aren't quite ready for primetime yet though. It'll be decades before we are getting energy that way, even if there was concerted research.

Except your gut is wrong. Recycling is not really clean. For some things maybe but not for everything (it uses far too much water).

Well, recycling might use too much energy to be clean (depending on how we get the energy), but using too much water doesn't seem a useful complaint, since cleaning and reusing water is just a matter of more energy.

Energy which, the parent argues, comes from un-clean sources - that's the complaint. How is this complaint not "useful", as long as you don't rebut it by listing those possible energy sources which you consider "clean"? Then I might be convinced and say: "He's right, dirty water doesn't matter, since we can just clean it, using this guy's clean energy sources."

The parent was arguing that recycling processes use too much water, which implies taking in fresh water and tossing it after "use". I didn't infer that the later energy discussion was part of that, since it seemed clear that filtering or distilling the water to clean it wasn't part of the assumed cleanliness of recycling. It would, of course, make it more expensive, but reducing externalities by such means makes the price reflect the true cost better, so that's all to the good, whether or not it turns out that recycling is really a good idea for a given material.

> There is a fact that no one wants to acknowledge: In timeframes of under 20 or so years there are NO energy technologies that are clean. None. For timeframes longer than 20 there is exactly one: Nuclear. There is nothing else.

I'm skeptical of this figure, but it's not particularly relevant. The issue is whether directing energy towards renewable energy production has a better environmental impact vs directing that same amount of energy towards fossil fuel energy production.

Total evaluations of the costs (in dollars, to the environment, etc.) are extremely important in comparing energy production methods, but your 20 year figure is fairly meaningless on its own.