Tuesday, March 30, 2004

So, where's the next kilowatt gonna come from?

Project Aqua - a large scale hydro generation proposal - has had - lovely irony this - it's plug pulled. Now, against a backdrop of increasing power demand and static generation capacity, folks are now asking the obvious: what's going to keep my business and my home a-hummin'?

A quick survey of the options:
Large-scale hydro: bzzzt - Aqua was to have used the last major resource that could be easily tapped. It had a high head and good flow, hence high energy potential. What's left tends to have one or other, not both, characteristics. And Aqua was in easy country geologically speaking.

Small-scale hydro: Maybe. But the same Byzantine processes of resource consent are needed, irrespective of project scale. Higher fixed cost equals higher running cost. And there will be a lot more generation points needed.

Geothermal: Maybe. That's if underground heat generated by vulcanism doesn't turn out to be a taonga, or be a major part of some taniwha's sustenance. And there's resource consent too...

Coal: probably. Although the Gummint doesn't like this turn of events: Govt Resists Coal Generation Option. Still, the vast lignite fields in Southland have to be a starter. The spectre of Kyoto is rather diminished these days, now that Russia has refused to ratify it. Oh wait, we stupidly signed up already? Sigh.

Nuclear: useful as a straw man to draw the impassioned bile of greens, and worth suggesting for the sheer sake of the ensuing spectacle. But chain-yanking aside, not, I think, a serious starter.

Wind: definitely possible, established in the Manawatu, but has already drawn NIMBY's in Christchurch (the sole generator, at Gebbie's Pass has had a rocky history, and the owners are still trying to quieten the gearbox, ferchrissake), and in Wellington, where a proposed Cook Strait facing wind farm got the evil eye from locals. The problem with wind is of course storage: power has to be used there and then (it does, after all, move rather quickly down them wires). So unless it's used to (say) pump water up into a hydro lake while the wind is blowing, it is rather useless for baseload generation, and by the same token, cannot be relied upon for peaks. And at around 0.5mW per tower, you need an awful lot of whirligigs to make even a modest amount of power. And then only sometimes.

Gas: maybe. Although we did seem to tear through the last major gas field we found rather quickly, no? The form of generation is here the major determinant: doing the gas jet under boiler, to steam - to turbine - to generator - to transmission, in a large centralised station, is not the most efficient usage of the potential. Dispersed generation - say via Stirling cycle technology like WhisperTech, is a better bet. That's big in the UK right now, especially for remote, isolated or small-cluster users. Watch this space.
Similarly, fuel-cells are another technology to watch.

But hey, there's another possibility! In the article, one of the NIMBY's down on the Waitaki river had this to say:

"there is a real head of steam developed for protecting the Waitaki River from such developments."

Quick: back up a turbine and generator, and hook 'em up to the grid!

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