22082011

Wind Power at least 6 times more expensive.

Is wind power expensive?

In oder to answer this question we need to find some figures giving the power to cost ratio. A recent article on the viability of wind power in Malta provide the necessary figures:

• Total cost of project 300 million Euro
• Total power generated 200 gigawatt-hours (Gwh) per year == 22.8 Megawatt per hour (divide by days and hours in a year)

Now for the more traditional power generation, in this case hydro (which some consider the greenest way to generate power), we can look at this article about a dam being built at Red Rock Reservoir in South central Iowa. The figures are:

• $220 million total cost
• Output will be 36 megawatts with a peak of 55 megawatts when the power is high.

Now, lets convert Euros to Canadian dollars which about 1.4 times - so the 300 million Euro becomes $420 million.



Now the ratios:

•  Hydro cost per megawatt = $4m to $6.1m
•  Wind farm cost per megawatt = $18.4m

Now given that wind farms have a different MTTF (mean time to failure) which is a lot shorter than a hydro facility, a known issue with wind farms in the industry, say less than half the period, you could incur costs with wind farms in maintenance at a higher level and sooner than with hydro.

Conclusion

I reckon on a cost comparison basis wind farms are anywhere from 6 to 9 times more expensive than an hydro for the same power output. Now I know this is 'rough' and based on a limited data set - but to have such a clear cost difference on such major projects indicates that this is no 'fluke'.

Food for thought..

Now the funny thing here is that the Hydro plant is being installed in Iowa - a State that just got to 20% of its power from wind farms - if wind farms were so darn good, why are they building a hydro plant? Maybe they need a reliable base load power source for when the wind does not blow; so in effect they are spending at least 6 times over for that wind power when they could have gone completely hydro (assuming availability). This is why I'm all for more hydro, it just makes good sense.

Update - capacity factor looks like it is taken into account

Unless I'm missing something from the wind farm report they expect to generate 200,000 MW a year from up to 24 wind turbines with up to 126 meters diameter - I make that 0.95Mw/h 24x7. I reckon at 126 meters in diameter that's a 5MW turbine - so they are running about 20% capacity factor - which is typical.