What the best use for the space around and under solar panels? Also, how do we power Puerto Rico?

As utility scale solar farms take up more and more land, finding ways to make use of the space around the panels is a growing opportunity. Also, Puerto Rico’s residents pay some of the highest utilities rates in America while getting some of the least dependable service. Is solar the answer?

Farming on the farm

Converting the grid to renewable energy in the U.S. is going to take time, money and hard work.

And land. Acquiring the land to host utility scale solar farms is a big part of the cost of growing the U.S. solar capacity, and increasingly, the use of land for solar energy generation is becoming a political topic(1). Finding creative places to put solar panels and imaginative uses for the land under utility scale solar is becoming more important in the energy transition.

Agrivoltaics is a blossoming field for leveraging the acreage under solar farms. Some crops, such as broccoli, have been proven to grow well under the partial cover of solar panels. (2) And in Kenya, the shade has even been shown to increase yield while reducing evaporation. (3)

Worldwide, collocating commercial beekeeping facilities among solar panels has become an increasingly popular choice. Even raising livestock is a viable option.(4) Sheep, in particular, have become a popular choice to help keep the undergrowth around panels in check. (5) On Thursday, the U.S. Department of Energy announced $8 million in funding for agrivoltaics at six research institutes across the country. (6)

sheep on a solar farm

Getting a twofer

Although it’s not technically land use, Solar Duck’s solar project will float 5 Mw of solar panels under the turbines of a North Sea wind farm (7), leveraging a space already devoted to energy generation and providing a model for land-based wind farms.

cars parked under solar panels

Park it where the sun does shine

One of the most promising dual uses for solar generation is using the vast stretches of parking lots in America as sites for solar generation. France’s Senate recently passed a law requiring many parking lots to cover half their area with solar panels.(8) Disneyland Paris’ parking lot installation is producing 10 GWh annually and will eventually bump that number all the way to 36 GWh. (9) These types of solar installations have the added benefit of producing energy adjacent to where it’s consumed, reducing the need for energy transmission infrastructure. In addition to helping power the theme park, the facility is also a boon to customers, providing their vehicles with shade on hot sunny days and offering shelter during rain and snow.

The U.S. is primed for this kind of dual use. With roughly eight parking spots for every registered car in the U.S. (10), there’s lots of space available. Time Magazine most conservative estimate is that there’s at least enough viable parking space in U.S. to generate roughly one third of the country’s energy needs, even if we only cover half of that space. On the upper end, it’s possible that there’s enough space for four times our power needs. (8)

Of course, if covering car parks isn’t practical, homeowners can always put solar panels on their roofs. The NREL estimates that rooftop solar can generate 36 percent of the country’s energy needs. (11)

The transition to renewable energy is going to require creative problem solving. Finding places where solar energy can be harvested while the land can continue to be used for other purposes will make the process less costly and speed progress.

puerto rico village

Is solar part of the solution for Puerto Rico?

“The whole grid falls apart,” is how activist Lopez Varona described the effects of Hurricane Fiona to CNN in September (12). Although the storm clocked in as only a category 1, it still caused an island-wide blackout that lasted for weeks for many residents.

Puerto Rico’s power grid was outdated and poorly maintained even before Hurricane Maria devastated the island in 2017 and knocked power out for as much as a month and a half. The New England Journal of Medicine estimated over 4,600 deaths were caused by the storm, with over a third linked to interrupted healthcare due to extended power outages. (13)

Puerto Rico’s grid emerged from Hurricane Maria much more fragile than before, and outages have become endemic even in good weather. At the same time, residents pay a higher rate for electricity than anywhere on the continental U.S. With the average household income in the territory hovering around $21,000/year, cheap and reliable energy is key for turning the island’s economy around.

Following years of failed efforts to upgrade the grid, the Biden administration is now seeking $3 billion to invest in rooftop solar for the island. (14) The move comes after 50,000 rooftop solar installations proved to be some of the only reliable energy sources on the island in the weeks after Fiona.

A study by the National Lab of Renewable Energy showed that with the island’s abundant sunshine, rooftop solar has the potential to supply over four times the island’s power demands.

The decentralized nature of rooftop solar would make the island’s energy supply much more resilient in the face of increased extreme weather and offer a lifeline, both figuratively and metaphorically, to an American territory that continues to struggle with climate change recovery.

The Weekly Sunsong

Jose Feliciano was born in Lares, Puerto Rico in 1945 and moved to New York City when he was five. Although he came up playing coffee houses in Greenwich village in the 60s, his career blossomed in Europe, Latin America, and South America before his acoustic version of Light My Fire became a hit in the U.S. His Latin jazz performance of The Star-Spangled Banner during the 1968 World Series became a political flashpoint, upsetting much of the viewership and getting him banned on several radio stations. But the performance opened the door for the non-traditional renditions like Jimi Hendrix and Whitney Houston.

When he went into the studio to record an album of Christmas songs in 1970, the producer suggested he write an original song. Feliciano objected, saying writing a new song was impractical. Eventually brought “Feliz Navidad” into the studio, and the recording is still one of the most beloved holiday songs in the country, over fifty years later.

  11. Rooftop Solar Photovoltaic Technical Potential in the United States: A Detailed Assessment, NREL, Jan. 2016