Windmills

The recent explosions in Massey’s Upper Big Branch coal mine and on the Deepwater Horizon drilling rig highlight the tragedy of workplace fatalities.  Though improvement in statistical averages do little to lessen the loss of those whose loved ones have died, the American workplace has gotten safer which means fewer will be grieving.  The Census of Fatal Occupational Injuries reached a record low in 2008: 3.6 per 100,000 full-time workers. Yet with the recent noted losses in the oil and coal industries, some might think that workplace fatalities could be reduced even more by moving away from fossil fuels and toward renewable energy.  The facts suggest the opposite.

The largest source of new renewable energy is wind power, which accounts for 62 percent of renewable electricity generation.  The Bureau of Labor Statistics doesn’t publish accident data specifically for the wind-power industry, but the Caithness Windfarms Information Forum(CWIF) has created a list of fatalities for the wind industry worldwide.  The list is compiled from news reports and is unlikely to be comprehensive.

That there are any fatalities in this industry should not be surprising.  Towers for modern wind turbines can rise 300 feet or more and the blades for the rotors extend another 150 feet beyond that.  (For comparison, note that the Statue of Liberty on its 150-foot granite pedestal reaches 305 feet.)  A single wind farm can require erecting a thousand of these 450-foot structures.  How many fatalities have there been?

Taking the CWIF fatalities for the U.S. and removing deaths that are only tangentially related to wind power, shows that there were 10 deaths in the wind-power industry over the years 2003-2008.  This would seem to make wind power much safer than coal mining, which had 176 fatalities over the same period.  However, much less energy was generated by wind than by coal.

To project changes in workplace safety from switching to wind from coal, it is necessary to know the mortality rate per megawatt-hour.  The low number of total deaths in the wind-power industry is undermined by the very low amount of power generated by wind.  Adjusting for power production yields a surprising result.  On a million-megawatt-hour basis, the wind-energy industry has averaged 0.0220 deaths compared with 0.0147 for coal over the years 2003-2008.  Even adding coal’s share of fatalities in the power-generation industry, which brings the rate up to 0.0164, still leaves wind power with a 34 percent higher mortality rate.  For the record, the workplace fatality rate for wind also exceeds that for oil and gas on an equivalent-energy basis.

Meeting the 20 percent renewable energy standard from the Waxman-Markey cap and trade bill with wind power would require swapping about 800 million megawatt-hours of coal generated current with 800 million megawatt-hours of wind power.  Using the recent mortality rates as a guide, we would expect there to be 4-5 more workplace fatalities per year than if there were no wind power at all.  Even this comparison ignores the fatalities we could expect from the additional power lines needed for so much remote wind power.

Certainly the impetus for moving to wind power did not come from concern over workplace fatalities.  However, the story of wind and safety illustrates an important dimension of the energy debate—there is a lot we don’t know about the impact of forcing dramatic shifts in our energy portfolio.  At small levels of production, negative impacts might be overlooked or even misinterpreted.  For instance, the energy inputs needed, the environmental costs, and the impact on the food supply were significantly underestimated by many who promoted ethanol as a substitute for gasoline.  Now that ethanol consumes roughly 30 percent of our corn crop, these impacts offer a sobering reality check on the previous euphoria.

Further refinements on mortality rates for wind energy may show that it is relatively better or worse than this first cut at the estimates.  But what we see when we look deeper is that due, in part, to its unreliable nature, wind power is an imperfect and very expensive substitute for conventionally-generated electricity; that it takes huge amounts of land; and it’s not so good for some components of the environment like bats.   The argument for forcing consumers to buy increasing amounts of wind power gets weaker the more we investigate its full impacts.

Wind Coal
Year Million MWh Deaths Deaths/Million MWh Million MWh Deaths Deaths/Million MWh
2003 33.705 1 0.0297 1973.737 27 0.0137
2004 41.618 1 0.0240 1978.301 26 0.0131
2005 52.169 1 0.0192 2012.873 22 0.0109
2006 77.374 1 0.0129 1990.511 47 0.0236
2007 99.941 2 0.0200 2016.456 28 0.0139
2008 150.645 4 0.0266 1985.801 26 0.0131
TOTAL AND AVG. 455.413 10 .0220 11957.679 176 .0147

Authored by David W. Kreutzer Ph.D. and Cameron Parker