Wednesday, June 22, 2005

Energy: coal is unnecessary and unwanted

Lee Neal has an op-ed in today's Herald arguing that "coal could be the answer to our problems". But what problems? The fact we've got too much of it?

Those pushing coal argue that we need it in order to meet the ongoing growth in electricty demand. But looking at the numbers shows that this is simply false. Our gross demand grows by about 150 MW a year - meaning that we need to be installing that much generation every year (on the average) if we are to avoid blackouts at some stage in the future. But the point missed by coal-advocates is that we are meeting this target. In fact, we're more than meeting it - and we're not doing it with coal.

Over the past few years a silent revolution has taken place in New Zealand's electricity sector: wind power has come of age. Last year we commissioned 132 MW of turbines and consented another 106 MW. This year, we've seen resource consent applications lodged for almost 400 MW of turbines so far, and Meridian last month announced plans for another 210 MW at Makara near Wellington. This puts us well ahead of the game, and from wind power alone. So what's the need for coal?

Coal generation is unnecessary. And, as the overwhelming public opposition to Mighty River's proposed Marsden B plant shows, it is also unwanted. We're better off leaving it in the ground rather than polluting our air and the globe by burning it.


Dang it, Idiot, you're doing me out of a job - the oil and coal industry is about the only way I can get employment in NZ, barring waiting for one of my old lecturers to die and then fighting tooth and nail with my old classmates for the position.

But seriously, there's bugger all problem with coal these days, emission wise - all they need to do is put a scrubber and a pump on the furnace chimneys, and pump the gas into a handy cavity (usually the old mine workings) full of water and carbon dioxide fixing bacteria (in effect, an artificial black smoker, like those beloved of deep sea bugs around submarine volcanoes. The only reason most coal generators haven't so far is that they're still allowed to just let it go straight up, and they don't like cutting their profit margins by the little bit required to run the scrubbers. Its still a shiteload better energy density than wind, and less damaging to the landscape than hydro.

Besides, even if we don't mine the coal for electricity, we still need to mine it for metal smelting, and even hybrid cars still use steel and aluminium frames.

Posted by Weekend_Viking : 6/22/2005 12:39:00 PM

Particulate emissions can be reduced and efficiency improved by using gasification as well - but the problem with Marsden B is that they are not planning to do any of the above. And the reason, as you point out, is that the policies aren't in place to force energy companies to do so. Until they are, then we simply shouldn't be burning coal.

This doesn't stop us from using it for other things, of course.

Posted by Idiot/Savant : 6/22/2005 01:27:00 PM

Why not just leave the coal in the ground for future generations? If we don't need to use it then keep it as a kind of long term savings deposit.

The way other industrialised countries are consuming non-renewable resources we may look forward to a time when coal will be worth far more as a source of minerals and chemicals than as a fuel.

With a little less selfishness now we could give our great grandchildren the opportunity of living in a very wealthy country.

Posted by Anonymous : 6/22/2005 08:49:00 PM

As Gary points out, the coal in the ground is just going to become more valuable. And coal can be used as a transport fuel or chemical feedstock - hydro or wind power can't (without a lot of mucking about with electrolysis).

Personally, I don't see what the fuss is about new hydro - the landscape of the Waikato valley doesn't seem to be much affected - I find the lakes quite attractive.

BTW, modern iron smelters (and all aluminium smelters) use electricity, not coal AFAIK. (and scrap, not ore - basically most of the iron the world needs has already been reduced from ore and just needs recycling occasionally).

Posted by Rich : 6/23/2005 11:16:00 AM

Rich: Funny, last time I looked we were still exporting all our best coking coals to China and Japan for their iron industry, and I've worked in the huge iron ore mines in West Australia (still going strong when I was there two weeks ago) which supply those smelters. While electrical smelters are used in the big developed nations, much of the third world and china still use big coke-fueled smelters for pig iron production, which is then alloyed to the various steels in electrical smelters. Aluminium smelters are electrical, but the cryolite baths use carbon anodes and cathodes which need regular replacement (every few months, apparently), and are, strangely enough, made from coal.

Hell, I've just come from a site in WA where they're surveying in a new iron ore mine at Mt Hale, which should last barely 10 years if they are lucky.

Posted by Weekend_Viking : 6/23/2005 04:46:00 PM