(no subject)

[commodorified]

Snaffled from ars technica

Stanford researcher Mark Jacobson likes to take current thinking about renewable energy and supersize it. Rather than aiming for 50 percent renewables, like California is, he has analyzed what it would take for each of the 50 states to go fully renewable. It would apparently involve so many offshore wind turbines that hurricanes headed toward the States would be suppressed.

I feel like that's an unalloyed good, am I missing something here?

Comments

[graydon]

You can't build wind turbines that strong that are also useful when light zephyrous breezes are blowing. You really can't build offshore wind turbines in quantity without knowing how much and how fast the sea level is going to come up over their operating lifetime, and no-one knows that. You totally do not want to concentrate zones of extraction for that much energy because that's going to do something else screwy to the already increasingly screwy weather.

You absolutely cannot do everything with renewables because renewables are intermittent and need is not; particularly things like glass and aluminium and steel refining/remanufacturing.

So there has to be some kind of storage mechanism and even if it's very efficient (~70% in and ~70% out, really quite good for batteries) it about doubles your energy needs. (So you don't want to do this for primary refining even if you do, desperately, want to do this for transport.)

So in general offshore wind turbines are a stupid waste of resources; building a lot of fragile fixed infrastructure and laying submarine high tension cable and otherwise spending a lot of money you shouldn't.

Ocean wind is a great energy resource, and you can perfectly well capture it by using sailing ships; drag the prop ("shaft alternator") to generate electricity, use the electricity to make ammonia, come to port, pump out the ammonia, crew gets a couple pub nights, repeat. All those pylons and other fixed infrastructure not required. Sailing ships well-understood. Diffuses the energy extraction, provides ongoing jobs, and would be a dandy, dandy industry for Newfoundland and the Maritimes generally. (Alberta is tougher. But someone smarter than me can probably figure it out, too.)

(Ammonia is a good pumpable fuel; it's pretty much the best pumpable fuel for fuel cells. Combination first demonstrated in a car at highway speeds in 1968. Well-understood ammonia handling technology already developed. Three different catalytic processes for ammonia synthesis from air and water (good old NH3, right? No carbon at all...) around 70% efficiency have been demonstrated, despite funding on a shoestring scale. There are people claiming .2 CAD/litre costs of production...)

[sara]

Enh, my understanding is they've had some successful pilot projects in the Mediterranean. It might be a go. And the whole appeal of the floating ones is you can re-moor them when sea level rises, which is hard to do with fixed offshore wind like they're building in the UK.

That said, when I was asked to review a proposed set of floating windmills recently, I didn't feel that the project proponent could explain very well what would happen if the turbines came detached from their moorings, about 1/4 to 1 mile offshore, and washed up on the beach. Or washed up on the liquid natural gas shipping terminal. I thought the answer might be "extremely bad things," and they insisted that nothing would ever go wrong, and I declined to consider that an adequate answer.

Aluminum manufacturers are actually pulling a lot of their juice from wind farms in the Columbia Gorge right now, that seems to be working fairly well for them. If they've got the wind in the day and the hydro at night they chuck along ok. It's better during drought years to limit the water releases through the dams and the availability of wind helps them moderate that.

[graydon]

I salute and thank you for declining "nothing would ever go wrong" as an adequate answer. That is laudable good sense too rarely lauded.

As I understand the floaty ones, you've got an inescapable choice between "can sink?" (buoy stability) or "can flip?" (plank/raft stability) and neither lets you not have to adjust the anchor placement if the depth changes significantly. (Which can be just from scouring, never mind actual sea level rise.) And neither gets you around the nasty corrosion problems inherent in salt water. I've got a preference for leaving those as close to the really well understood problem domains as we can possibly get them.

Pulling some juice from wind farms is good. Can't plan the plant around it, though. Which is why Iceland will likely keep exporting electricity in the form of aluminium for a long time. And why we've got an interesting problem replacing all the stuff that currently solves "process heat?" with "gas, natural, shedloads of, fire, for the lighting on".

[sara]

Yeah, I think they can actually tack a second, longer cable on there if they have to.

There are enough submerged cable projects that I think the engineering is not insoluble; I just don't know that I think the failsafes for this particular application were sufficient. I also didn't think they'd done enough to address visual impacts -- there are coatings you can use in a marine environment that will make things more-or-less disappear visually on an overcast day, but the pilot project wind farm people REALLY want you to be able to see their EXCITING GREEN ENERGY PROJECT from a distance (ohboy).

This is the second phase of the Portugese pilot. It is at a much shallower depth than the proposed project I reviewed, but it's still interesting to watch it built out.

There is no one solution with renewables but it's good to see people playing around with different options.