Wednesday, July 18, 2012

Renewable energy can't meet demand for electricity

via PrairiePundit by Merv on 7/16/12

Robert Bryce:
It's summer. It's hot. And once again, we are hearing from the usual suspects that we must change our entire way of living. Repent, they say. Carbon dioxide emissions are killing Mother Earth. Give up hydrocarbons and embrace renewable energy. 

Doing so, we're assured, will result in a gentler climate and myriad other benefits, including scads of "green" jobs. Sounds easy, no? 

Alas, no matter how much they may wish it to be so, the proponents of alternatives -- and better yet, "clean" energy -- cannot overcome the problem of scale. A simple bit of math shows that even with the rapid expansion that solar and wind-energy capacity have had in the past few years, those two sources cannot even meet incremental global demand for electricity, much less make a dent in the world's insatiable thirst for coal, oil, and natural gas. Indeed, had any of the myriad advocates for renewable energy bothered to use a simple calculator, they would see that their favored sources simply cannot provide the vast scale of energy needed by the world's 7 billion inhabitants, at a price that can be afforded. 

Consider this: between 1985 and 2011, global electricity generation increased by about450 terawatt-hours per year. That's the equivalent of adding about one Brazil (which used 485 terawatt-hours of electricity in 2010) to the electricity sector every year. And the International Energy Agency expects global electricity use to continue growing by about one Brazil per year through 2035. 

How much solar would be needed to produce 450 terawatt-hours per year? Well, Germany has more installed solar-energy capacity that any other country, with some25,000 megawatts of installed photovoltaic panels. In 2011, those panels produced 18 terawatt-hours of electricity. Thus, just to keep pace with the growth in global electricity demand, the world would have to install about 25 times as much photovoltaic capacity as Germany's total installed base, and it would have to do so every year. 

Let me repeat that: just to meet the world's increasing demand for electricity -- while not displacing any existing electricity-production facilities -- the world would have to install about 25 times as much photovoltaic capacity as what now exists in Germany. And it would have to achieve that daunting task every year. 

The scale problem is equally obvious when it comes to wind. In fact, wind-energy's scale problems are even more thorny because wind energy requires so much land.
There is much more.

It is not going to happen even if Obama spent the whole budget on this fantasy.  The current solar and wind generation capacity is just to inefficient and inconsistent to merit that kind of investment, if we had the money.  Natural gas is going to be the dominant fuel of the future right now.

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