Any approach to determining economic policy for climate change should take into account the possibility that the current understanding of the atmosphere may not be translatable into reliable forecasts with a precision that allows the design of an economic response. Further, any economic forecasts that are used to construct models of future carbon use and carbon dioxide emissions will be unable to deal with technical innovations. Their success cannot be predicted. This impacts on policy in two ways, first the obvious uncertainty in estimating economic development but more immediately the desire of governments to stimulate technical solutions. The need to be seen to be taking action frequently descends to picking winners and creating classes of rent seekers. ...As an example the present subsidies for wind farms are a response to demands for action from Green groups and green politicians. The result is a new rent seeking group. There is little cost benefit analysis to guide policy development. Rather policy is set to subsidise non-competitive technologies that may produce unquantified benefits. A simple comparison with the more conventional alternative of natural gas shows the use of gas to be more cost effective and useful as gas turbine generators produce electricity on demand. General encouragement of innovation should be the limit of government policy. It is hard enough in business to develop innovations and well beyond the reach of general government.

The wind rush is on. Plans to erect sweeping wind farms are being unfurled at a rate of knots. But is this really clean green energy, or just another case of greedy corporates trashing our landscapes for profit? Anton Oliver argues it's about time New Zealanders woke up to the dark side of wind power.

The starting point is the broad brush statement in the paper that no power supplies are perfectly reliable. This is correct provided you don't ask about the details. If you did, the devil would point out that there is a difference between a naturally intermittent supply and a supply which trips or goes off line unexpectedly. There is a difference in scale and time. Contemporary distributed electricity systems have devised ways of insuring continuity of supply for the latter events but are struggling to deal with the former. This is not comparing like with like. ...Intermittent supply adds an extra stretch for the control of a network. Wind farms illustrate the problem. A standard measure of the performance of a generator is the capacity factor. This is the annual averaged power achieved as a percentage of the installed (or maximum) capacity. ...But this factor gives no indication of the detailed performance. A measure that helps give an indication of this is a reliability figure. This is the minimum percentage of power that may be relied upon for 90 per cent of the time. For wind farms it is about 5 to 10 per cent

There, in a nutshell, is the twin problem with wind. On average, across a year, you might get 30 per cent of its theoretical capacity, but often you get zero or so close to zero as not to matter. It happens frequently and at any time; and when the wind chooses, not you. "Somebody", therefore, has to keep unused surplus capacity in some other form of generation equivalent to all the wind generation capacity. And keep it either operating, or able to at the flick of a switch.

Germany has 18,300MW (megawatts) of installed wind capacity -- close to half Australia's total installed electricity generation capacity, about double Victoria's. E.ON Netz draws on 7600MW of that. In the precise German way, it tells us that maximum feed-in was 6234MW at 9am on 15/12/05. Sound great? Except when you read the minimum feed in, at 12.15pm on 27/05/05. Just 8MW. And no, I'm not missing a nought or two. Some 7600MW of installed capacity delivered just 8MW. When the wind don't blow, the electricity don't flow. On average across the year, the 7600 MW of installed wind capacity produced 1327MW. That's an operational level of 18 per cent of capacity. In rational terms, it's insanity.

The talk in the local community is that five of the 12 turbines at Toora are now shut down because of equipment failure, the warrantee period has expired and they can't get parts. This wind farm is not particularly old and it's now limping along with a 42% reduction in power output. It's probably a good time to get this junk off the Toora hills....... This mucking around with turbines all adds to the cost of something that is nothing more than a hoax, which would all be pretty funny if it wasn't subsidised by the public purse.

Editor's Note This opinion piece was submitted to IWA in pdf form and is available in IWA's reference library via the link provided below.

Like most really thoughtful environmentally concerned scientists, I'd rather a tiny amount (in metric tonnes or cubic metres, after decades of use) of stored radioactive waste than the unmitigated disaster of millions of tonnes of carbon dioxide released into the atmosphere. And renewables are not realistically and politically going to fill the gap any time soon.

But if the nation is going to go nuclear, should we not play a role in developing a better, safer form of this energy?

Local power generation could be achieved by installing tidal turbines in Auckland's regional harbours. Two harbours are superbly suited for this purpose, and tidal-current power generation is cost-effective and environmentally friendly.