Solar/wind power: A matter of land area?

The Obama Administration has long pushed solar and wind power as the preferred renewable energy replacement for fossil fuel electricity. Is this a realistic possibility?

The Administration must think so. It has poured tens of billions into research and deployment of solar and wind energy in large-scale commercial electric power projects.

To show off Administration solar power investments for reducing carbon dioxide emissions, U.S. Environmental Protection Agency (EPA) Administrator Gina McCarthy toured the William R. Sinkin Centennial Solar Farms outside San Antonio, Texas on February 12, 2014.

Sinkin is a new state-of-the-art 20 megawatt (MW) solar photovoltaic facility occupying 200 acres of land. Gina McCarthy toured it along with San Antonio Mayor Julián Castro and other dignitaries.

Supporting state and local efforts to address the effects of climate change – such as more frequent and severe extreme weather – is an important part of President Obama’s Climate Action Plan
EPA Press Release,  William J. Sinkin solar farm, San Antonio, 2/12/2014

Solar and wind are vital cogs in the President’s visionary Climate Action Plan to reduce U.S. greenhouse gas emissions by 2020.

According to the U.S. Energy Information Administration (EIA), the United States will consume 4.086 billion megawatt-hours of electricity in 2014. That’s huge. It is 121,000 Sinkin-sized solar farms!

Can solar and wind power become the mainstay of electricity production in the United States? Even overcoming their other disadvantageous, it’s a matter of land area!

The Capacity Factor

Understanding capacity factors is key to understanding electricity production in the United States. It’s crucial when talking about both solar and wind power.

Typically, an electric power plant is described by its generating capacity, usually expressed in megawatts (MW). Sinkin, for example, is described as a 20 megawatt solar farm.

However, generating capacity isn’t always an accurate measurement of a plant’s true electricity production. No power plant delivers 100 percent of its generating capacity. It delivers less. How much less depends on the energy source.

Nuclear power plants are the most efficient. They run at close to their rated generating capacity 24 hours a day all year long. For example, the Palo Verde Nuclear Generating Station near Phoenix, Arizona operates at 90 percent of its rated capacity.

Palo Verde is the largest electric power plant in the United States. It has 3,875 MW capacity and delivers 30,584 gigawatt-hours (GWh)/year when operating at 2013’s measured 90.1 percent capacity factor.

Solar and wind, on the other hand, both have exceptionally low capacity factors. According to the EIA, solar photovoltaic operated at only 19.4 percent of capacity in 2013. Wind operated at 32.3 percent. Solar thermal operated at just 17.8 percent.

Of course, solar produces only when the sun shines and wind only with a blowing breeze.

Solar solution

The Sinkin solar photovoltaic (PV) farm requires 10 acres of land area for each megawatt of electric generating capacity. Its 200 acres occupies 0.31 square miles split between two plots.

A Sinkin-like solar PV farm, at 19.3 percent capacity factor, would have to have a whopping 18,043 MW of rated capacity to produce the same amount of usable electricity as the Palo Verde nuclear plant.

Palo Verde occupies 6.25 square miles. Sinkin would need 282 square miles of solar panels on a single plot of land to match Palo Verde’s output. That’s about the size of New York City.

To produce all the electricity in the United States with solar photovoltaic panels would require a land area of 37,790 square miles. Solar thermal would require more. That’s one third the size of the state of Arizona.

The Obama Administration has opened up public lands to solar and wind power. Solar PV would require 14 percent of all the BLM managed lands in the continental United States to meet current U.S. electricity needs.

Wind Solution

845 MW Shepherds Flat Wind Farm near Arlington, Oregon

Wind power needs even more land than solar for its tall windmills.

The 845 MW capacity Shepherds Flat Wind Farm on the banks of the Columbia River near Arlington, Oregon was the largest in the world when it opened in late 2012.

It has 338 windmills on two large plots of ranch land occupying 30 square miles in two counties.

Wind has a higher capacity factor than solar, but takes up more space. To match Palo Verde’s usable electric output, Shepherds Flat would need 460 square miles. That’s nearly the size of Los Angeles.

To produce all the electricity in the United States it would take up half the state of Arizona, over 22 percent of all existing public BLM lands in the continental United States.


Solar and wind have numerous important physical limitations:

  • Non-scalable. They can’t be turned on or off to adjust to peak electric needs.
  • Inefficient. They have exceptionally low capacity factors. They are probably operating near their theoretical limits now.
  • Siting. Must be built where conditions are suitable, not necessarily where electricity is needed.
  • Land. Require vast land areas to produce significant amounts of electricity.

Suitable land area is a serious obstacle to both solar and wind power. Most people just assume there is enough. It’s likely there isn’t enough suitable land in the continental United States to come close to current electric needs, let alone future ones. If electric cars catch on consumption will skyrocket.

Wind and solar provide less than five percent of electricity in the United States despite 10s of billions in government subsidies. Subsidies can’t be sustained forever.

The Administration talks the talk about an all-of-the-above energy strategy. Solar and wind economics will soon force the Administration to walk the walk.  Solar and wind disadvantageous prevent their adoption as the primary source of electricity in the United States.

EIA data suggest that lower-cost, low emission natural gas and nuclear are the more viable energy solutions for electricity over the next 25+ years.


About azleader

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Posted on Feb 24, 2014, in climate change, economics, Economy, EIA, Energy, energy policy, environment, Government, green energy, news, Politics, science, solar power, technology, wind power. Bookmark the permalink. 7 Comments.

  1. Most climate skeptics are in aware that the spirit of Stalin survived the end of WWII, and will not be easily defeated now. Punishing the likes of Michael Mann etc. is useless.

    In 1946 George Orwell started writing his warning to us.

    In 1946 Fred Hoyle said the internal composition of the Sun was changed from iron (Fe) to hydrogen (H) and was unanimously adopted without debate or discussion. See pp. 153-154.

    Precise experimental data on pages 19-27 of my autobiography identify most of the falsehoods that led us into slavery.

    • Most climate skeptics are unaware . . .

    • This article has nothing to do with Stalin, George Orwell or WWII… nothing! It speaks to one issue… the viability of wind and solar as primary sources of electricity in the United States.

      • Do you really think they are unrelated?

        Why has not one of the 97% consensus scientists stepped forward to dispute nine pages of precise experimental data that falsify standard models of stars and nuclei?

  2. Phoenix Solar Thin-Film Photovoltaic plant, located near Changi North Industrial Park, is Singapore’s biggest thin-film photovoltaic (PV) power plant. It was designed and built by the Singaporean subsidiary of Phoenix Solar

  3. Comparing land use and capacity factor are just two of the many many different parameters that electricity generators have, and all stable electricity generators typically are most economic with a mix of generation technologies. The article premise is like saying don’t Bananas don’t have vitamin C, therefore we shouldn’t eat them.

    On Land use: Solar can be sited to a HIGH degree on rooftops and otherwise unused land and is a harmless neighbour. Nuclear usually is sited next to a big water resource and with large buffer spaces, plus their centralized nature means sizeable transmission line requirements (also requiring space). Land where wind turbines are situated can still be used for agriculture, thus a double crop of existing land.

    On capacity factor: Nuclear can *only* operate at a high capacity factor, so is unsuited to providing peak demand. Peaker plants, a key part of most grids, operate at <25% capacity factor due to these operational needs. Solar matches peak demand quite well, so can be an important part of the generation mix. A mix of solar plus wind also provides an attractive hourly generation profile.

    On intermittency – there are logical engineering solutions to minimize effects of the intermittency : aggregation of many sites, combination of renewable energy + storage, forecasting, overbuilds, etc that are being incorporated into leading edge utilities at cost competitive prices now, and the costs will only get better with further improvements.

    • You are correct that rooftop solar helps with the land area problem. It’s smart to use existing area (rooftops) to add solar without taking space away from agriculture or other purposes.

      You are wrong saying, “Solar matches peak demand quite well, so can be an important part of the generation mix.”

      Solar and wind both are non-dispatchable. That means they cannot be turned on and off when needed. For example, you can’t crank up solar to provide heat during a blizzard.

      Fossil’s on the other hand are dispatchable. They can be cranked up to provide heat in blizzards and air-conditioning in heat waves. They can be turn off just as fast the moment they aren’t needed.

      Nukes are perfect for base-load power sources, which is exactly how they are used. Dispatchable energy sources fill in the gaps.

      Fossils are perfect for both base-load power AND dispatchable power. They provide the best of all worlds.

      Solar and wind, on the other hand, are irregular, unreliable energy sources. They have to be used at generation time regardless of need or conditions. In that regard, they represent the worst of all worlds when it comes to electric power generation.

      Your suggestions to solve the solar/wind intermittancy problem are vastly expensive and completely unnecessary. Natural gas advanced combined cycle is the most practical, most plentiful and lest expensive electric energy source there is.

      If used to replace coal-fired power plants, natural gas combined cycle will cut electric power sector CO2 emissions by half.

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