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Argument Over the Value of Solar Focuses on Spain

Analysts disagree on whether the energy returned from solar is worth the energy invested

4 min read
photo of photovoltaics in Cuervo, Spain, under scrutiny
Photo: Flip Franssen/Hollandse Hoogte/Redux

Oil producers are working harder than ever to replace their reserves and, increasingly, turning to nonconventional petroleum sources such as Canada’s tarry bitumen and ultra-deepwater offshore wells. As they do so, they are investing more energy to deliver each new barrel of oil. Similar trends are playing out for natural gas and coal, and a growing number of energy analysts are worried. They see these accelerating trends—what they call fossil fuels’ declining energy return on investment, or EROI—as an ill portent for the global economy.

The critical question for the future is whether renewable energy sources can fill the gap, sustaining the energy surplus that has supported explosive growth in human life span and population since the industrial revolution. A book due out later this year promises a hard-nosed look at solar energy—the fastest growing form of renewable energy—and is likely to raise plenty of eyebrows.

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This photograph shows a car with the words “We Drive Solar” on the door, connected to a charging station. A windmill can be seen in the background.

The Dutch city of Utrecht is embracing vehicle-to-grid technology, an example of which is shown here—an EV connected to a bidirectional charger. The historic Rijn en Zon windmill provides a fitting background for this scene.

We Drive Solar

Hundreds of charging stations for electric vehicles dot Utrecht’s urban landscape in the Netherlands like little electric mushrooms. Unlike those you may have grown accustomed to seeing, many of these stations don’t just charge electric cars—they can also send power from vehicle batteries to the local utility grid for use by homes and businesses.

Debates over the feasibility and value of such vehicle-to-grid technology go back decades. Those arguments are not yet settled. But big automakers like Volkswagen, Nissan, and Hyundai have moved to produce the kinds of cars that can use such bidirectional chargers—alongside similar vehicle-to-home technology, whereby your car can power your house, say, during a blackout, as promoted by Ford with its new F-150 Lightning. Given the rapid uptake of electric vehicles, many people are thinking hard about how to make the best use of all that rolling battery power.

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