Tag Archives: Land Use

How Much Land Would it Take to Generate All US Electricity With Solar Alone?

An in-principle calculation demonstrating how little land is really needed

Renewable energy resources are more diffuse than concentrated fossil energy, requiring wind farms spread o’er many leagues, and array upon array of solar panels. But is this a fundamental barrier to employing renewables at scale, as some would have you believe? The answer is nay, and it can be quickly seen from some back-of-the-envelope calculations (and with the assistance of some pretty maps), that no more than 7,000 square miles of photovoltaic panel surface area would be needed to generate 100% of US electricity. This is less than 0.2% of the contiguous US land area, and a small fraction of urban area in the US.

This demand could be satisfied with existing rooftops and other impermeable surfaces, such as parking lots. And of course, no all-renewable portfolio would actually be 100% solar, but this exercise shows that land area is not a limiting factor in scaling solar.

To inform our calculations, let us first introduce some fundamentals concerning solar resources…

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Paper of the Day: Poore & Nemecek (2018): Reducing food’s environmental impacts…

Synopsis

A new analysis drawing on 570 studies with data covering 38,700 commercial farms shows dramatic variation both worldwide and within-region in the environmental impact across all major foods, but confirms that beef in particular and animal products in general are responsible for the greater part of food’s impact on earth, which adds up to 31% of global warming emissions (including non-food agriculture), and 43% of ice- and desert-free land.  Supplementary material available for free (and is very comprehensive), while the main article is for subscribers only (here).

Poore, J., & Nemecek, T. (2018). Reducing food’s environmental impacts through producers and consumers. Science, 360(6392), 987-992.

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