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Renewable energy is not dependable

Published 10:32am Friday, April 26, 2013

Unlike other commodities, electricity cannot be stored economically so production must match consumption on a real-time basis.

Turbines only work when the wind blows and solar panels only work when the sun shines.

Within the energy grid there must be a balance between the load and generation, but because of the varying levels of electricity produced by renewable sources this balance is hard to maintain, and poses one of the biggest challenges to the power sector.

An intermittent energy source is any source of energy that is not continuously available due to some factor outside direct control. The intermittent source may be quite predictable but cannot be dispatched to meet the demand of a power system.

Solar Energy

Intermittency inherently affects solar energy, as the production of electricity depends on the amount of light energy in a given location. Solar output varies throughout the day and through the seasons, and is affected by cloud cover. Solar does not produce power at night.

The inability to meet demand can result in a system failure where no one receives power.

Intermittency inherent in solar production may potentially result in large limitations to its value as a power source.

Wind Energy

Wind-generated power is also a variable resource, and the amount of electricity produced depends on wind speeds, air density and turbine characteristics. If wind speed is too low, they will not be able to make electricity, and if it is too high the turbine will have to be shut down to avoid damage.

The Australian Coal Association says because of the intermittency of wind, the percentage of the installed Australian wind generation capacity that is actually available on the average is just 25 percent to 40 percent.

The inescapable physical fact is that wind and solar power are not continuously available. “Since intermittent renewables by definition cannot provide a reliable supply of electricity, they must be backed up by conventional fuel sources such as coal, gas, hydro or nuclear.”

Renewable Energy

As we consider how to best transition to a greener energy economy, we must move forward cautiously and recognize that such a transition will take years, if not decades. How can we expect to reinvent in a few years what took a hundred years to build?

Joseph P. Smith


Pyro-Chem Corporation

South Point


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  • mickakers

    Joseph P. Smith; Your mental attitude is demonstrative of the past. I am thinking of those who were skeptical of the Horseless Carriage (automobile) and God forbid, the Flying Machine. However, I don’t think it is just mental attitude but profit that rules the roost when it comes to determining the best sources of energy in your very prejudiced and self-centered opinion.

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  • Geronimo

    In your and my lifetime , 79Tiger,but what about future generations , the demand for fossil fuels will be so great soon that only the very rich will have it , you know!! like China and the other countries that get slave labor from their citizens. How many more centuries can this Planet exist , before it runs dry ? Will we want to be prepared ?

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  • 79Tiger

    Get rid of all energy restrictions and all energy subsidies and the strongest will survive. The only thing keeping this country from being energy independent is the federal government.

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  • metta2uall

    This article ignores Solar Thermal plants, which store solar energy by using it to heat up materials like molten salts. The molten salts can then be used to boil water and spin a turbine, even at night. Several such plants are already in operation, including the the USA. After combining this with wind power, there will be a small amount of time when both aren’t enough (little wind after several days of rain) – this gap can be filled with gas, which can also be renewable in principle (biofuels).

    Researchers have already developed plans for Solar Thermal, combined with wind, combined with gas. Check out Beyond Zero Emissions and google for “Least cost 100% renewable electricity UNSW”.

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  • keta

    Oh, brother. Shame on you, Tribune, for giving these old pirates another opportunity to cheerlead for coal in your pages. We can’t continue to burn coal, end of story. Fairy tales about “clean coal” and advertisements masquerading as letters on opinion pages like this one are embarrassing and stupid. I’ll bet old Joseph has kids he cares about in his life, kids who need air to breathe, who need a planet cool enough to grow food, for heaven’s sake.

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  • mikehaney

    The Cardinal Mine in western Kentucky is among the most productive underground coal mines in the United states. It’s the thirty-fifth largest in American and produces about 6 tons of coal per miner work-hour.

    That’s about two times the national average of underground coal mines. On an average day, by itself, the Cardinal Mine, which has about 400 people on its payroll, produces about 75 percent as much raw energy as all of the solar panels and wind turbines in the United States, reports Robert Bryce. (1)

    Yet, according to Grist, solar power workers now outnumber coal miners nationwide. (2)

    Solar (and wind) have been big cash cows. In the time frame 2009 to 2011 the Obama administration distributed $9 billion in economic ‘stimulus’ funds to solar and wind projects that created, as the end result, 910 ‘direct jobs’—annual operation and maintenance positions—meaning that it cost about $9.8 million to establish each of those long-term jobs. (3)

    Coal provided 42% of US electricity needs in 2011 while solar provided 0.2% of US electricity needs. (4) As Steve Milloy notes: coal provides 210 times more electricity and suggests, “You do the math.” (5)-Jack Dini

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  • mikehaney

    Joseph P. Smith–Good article.
    Problem with solar and wind energy is that uncle sam, good ole taxpayer,is footing the bill. And losing big time.

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  • daddydan73

    The reality is that we already have a very sophisticated electric system in the US that can handle massive swings from generators of all kinds, including coal, gas, wind, etc. There is an extremely intricate scheduling system that is heavily regulated. Therefore, since electric demand will continue to rise in future years, it is imperative to add to the 60,000 megawatts of wind power that is already on the ground in the US.

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