Thursday, August 10, 2006

More puff than power -

We need renewable energy sources, but the answer's not blowin' in the wind, writes Geoff Strong.
SINCE Europeans began squeezing out Australia's riches, a magic-pudding mythology has wormed into our folklore. It's part of a fantasy that the land and its resources are endless and infinite. As Norman Lindsay's storybook character says, "the more ya eats, the more ya gets".
It probably explains how we are lulled by some of the claims of alternative energy. How often do we hear the mantra, particularly from politicians, "clean, green and totally renewable"?
Well maybe, but first read the fine print.
Wind farms are now the renewable energy source of choice, largely because they are a tested off-the-shelf technology that generates electricity. They are particularly attractive to big investors, such as union superannuation funds wanting to demonstrate that their investments are ethical.
Also they appeal to astute merchant banks that detect a public willing to pay more for an energy source they believe helps the environment, particularly with rules guaranteeing that any power generated will be bought.
For politicians, turbines are big and visible — tangible proof to a worried public that something is being done about human-induced global warming, a problem few people fully understand. Thus Victoria recently announced a wind industry free kick with a new policy to increase the number in the state.
Equally few people seem to understand electricity generation and the grid that distributes it. Some think power is stored in a giant battery down in the Latrobe Valley. Others (including some cabinet ministers), seem to think the system is like a lake into which energy produced can just be poured. In reality, it is more like the vascular system of an animal: inputs and pulse must be carefully regulated or things will go wrong.
Electric energy is one of the foundations of the civilisation we probably take for granted. In Australia, the economy underpinning that civilisation relies on electricity being fairly cheap. We have little else, such as low wages, to keep industries like manufacturing here. What sort of an economy would we have with Chinese rates of pay?
But do technologies such as wind really work and answer our clean energy needs? A decade ago, I was one of the wind-farm faithful, but after closer examination I have become an apostate. Global warming is real and the biggest threat to our planet and species. My main concern about wind farms is that they lull many into thinking something effective is being done, when I suspect it is not.

For starters, wind farms generate for only about 20 to 30 per cent of the time and it is only by chance that any power is generated when it is needed. Take the recent experience of the merchant bank spin-off Babcock and Brown Wind Partners. With 19 wind farms on three continents, the company has faced a $10 million profit downgrade because the recent heatwave in Spain and Germany led to "still wind". In other words, it did not blow when consumers wanted air-conditioning.
Australia's electricity supply on our east coast is managed by the National Electricity Market Management Company. It is charged with meeting demand with supply at the most economical price. In any power system, electricity comes from two forms, baseload and peak. The first are the big power stations that produce bulk electricity — in our state from brown coal, while nuclear power is touted as a greenhouse-friendly alternative.
Peak power usually comes from hydro or gas — more expensive, more environmentally friendly but able to be stopped and started according to demand.
Where does wind come in? In a sense it doesn't, because NEMMCO does not count it as power generation, because it can't be called up like other forms. Rather, it is classified as a drop in demand. As well, wind does not normally displace coal power, it displaces the more environmentally sound but expensive generators such as hydro-electricity and gas.
In addition, because of its unreliability wind has to be backed up to 90 per cent of its claimed capacity by other forms of generators. Also, the output is relatively low per dollar spent. The State Government has a report it won't release that sources have said confirms this.
Victoria's biggest power station, Loy Yang A, produces 2000 megawatts. The average wind turbine produces about one megawatt in ideal wind conditions. Imagine the area of the state that would need to be covered in turbines to replace the 6395 megawatts we get from coal. Don't forget to back it up about 90 per cent for reliability.
There are, however, alternative energies with baseload prospects such as using steam from underground hot rocks to power generators. Another intriguing project is the 500-megawatt solar tower, proposed for near Mildura, where a huge greenhouse would generate hot air to be sucked up a 500-metre- high tube, turning embedded wind turbines. The company behind it, EnviroMission, claims this also offers the renewable holy grail of being able to store energy, in this case in the heated ground.
While hard reality means clean energy might not be blowing in the wind, it might well be in the updraft.
Geoff Strong is a senior staff writer.

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