An addiction to fossil fuels

April 6, 2010 By Alvin Powell, Harvard University
Photo: Kristyn Ulanday

Clean, renewable wind and solar power may be the most-preferred fossil fuel alternatives, but their land-hungry collecting requirements make them difficult options for replacing more conventional power sources, according to a British energy expert.

David MacKay, chief scientific adviser to the United Kingdom’s Department of and Climate Change and a professor of natural philosophy in the Department of Physics at Cambridge University, crunched the numbers on how much energy some sources can generate per unit area to illustrate that renewable types probably will be part of a future energy mix, rather than the solutions.

MacKay, author of the recent book, “Sustainable Energy — Without the Hot Air,” said that to generate enough power to replace , some renewable sources would have to cover enormous swaths of territory. , for example, would have to cover half of Britain to meet that nation’s energy needs, he said, adding that he has been accused of being anti-wind for pointing this out. He’s actually pro-wind, he said, but quipped that he’s even more “pro-arithmetic.”

“The message about renewables is that, to make a difference, renewable facilities have to be country-sized,” MacKay said, noting that some people are already fighting construction of wind farms in areas they deem inappropriate.

MacKay spoke Friday (April 2) at the Northwest Laboratories as part of the “Future of Energy” lecture series sponsored by the Harvard University Center for the Environment (HUCE). MacKay was introduced by HUCE director Daniel Schrag, Sturgis Hooper Professor of Geology and professor of environmental science and engineering.

Though MacKay said moving to an all-renewable power system would be difficult, he also said the status quo cannot continue. Fossil fuels are not only warming the globe, they are a finite resource. In addition, he said, the need to import fossil fuels creates security and supply concerns. As much as 90 percent of should come from non-fossil fuel sources, he said.

“We have an addiction to fossil fuels, and it’s not sustainable,” MacKay said.

MacKay broke down current energy demands into simple units and then took a cut-and-paste approach with alternatives, saying he’s not particularly fussy about the exact combination that replaces fossil fuels, as long as it gets done.

The generating capacity per unit area of nuclear power plants is 400 times that of wind farms, making them a potentially useful part of a future mix. Besides wind and solar power, also in the mix could be clean coal plants and hydropower from unconventional sources, such as tides and ocean currents. MacKay also advocated decreasing demand by insulating buildings better, by switching to more efficient building systems such as heat pumps, by turning down thermostats, and by turning off appliances when not in use. Transportation, he said, should be predominantly electric-powered, and generation would be more efficient if plants were built in regions that get lots of sun, such as the Sahara Desert and the American Southwest.

“Getting off fossil fuels will not be easy, but it is possible,” MacKay said.

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not rated yet Apr 06, 2010
"Besides wind and solar power, also in the mix could be clean coal plants and hydropower from unconventional sources, such as tides and ocean currents."
-Clean coal is a joke, trust me it's not viable and would cost far more than nuclear in terms of construction and operational costs, and this would only remove 10% of CO2 emissions in the wildy high estimates. Clean coal is not an option because is infeasible, not economic, only theoretic and posses series concerns for human safety and the environment.
-tidle, wave and similar are viable options especially tidle power which is seriously under utilized and can provide a significant amount of power

-Though this article does mention the costs of global warming,, it makes no mention of heath consequences such as cancer, ocean acidification, dirty soot in citys and the plethoria of other negative consequences of fossil fuels.
not rated yet Apr 06, 2010
The problem here is that they think they need to cordon off huge areas and hage the solar panels off limits to regular people. This is so not the case. They could use existing real estate. Solar panels do not need to be bunched together to be effective. In fact they would work a lot better if they were close to the place they will be used.

In stead of governments buying huge tracts of real estate for a power plant, how about use that money to subsidize warehouses to install panels on their roofs? The govt in many areas doesn't get anything back for their investment of building a plant in most cases, so if they subsidize solar even half of what it subsidizes power plants, it will become a very affordable option for many warehouses who would love to cut their power bills and have reliable power during the day.

Just consider how many panels you could put on top of one of those new Walmarts....
not rated yet Apr 06, 2010
What bull! There is plenty of space available, it just doesn't make profits for utilities, banks, speculators, etc, it's called roofs, yards and parking lots.
Because the customers own them they don't have to pay for transmission lines, land costs or utility costs, profits making them 2.5-3x's as cost effective than utility ones. And since they last 25-50 yrs energy costs don't go up.
not rated yet Apr 21, 2010
Why not use the space in the Ocean? Floating Solar arrays should not be that infeasible - algae farms are another idea. Lots of space there!

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