As if the case for renewable energy needs any more making, along comes a new study showing that wind and solar power are good for the water table and they could help farmers survive periods of drought, too. That’s especially big news for California. The state has suffered through a series of droughts, leading to unsustainable use of its underground water resources by farmers and other users. But wait, there’s a weird hydropower angle in there, too.
Not All Renewable Energy Is Good For Farmers
Renewable energy has been a boon for farmers seeking to add another income stream to their revenue and cut their energy costs with wind and solar projects, including the emerging field of agrivoltaics.
Things get a lot stickier when you include hydropower in the mix. Hydropower is a form of renewable energy, but it’s not necessarily a benefit for farmers. Their need for irrigation peaks during periods of drought, which is right around the time when hydropower dams are especially cautious about releasing water for other uses.
All things being equal, the theory goes that agricultural water users would benefit from policies that accelerate wind and solar development at the expense of hydropower as well as fossil fuels.
The Wind & Solar Solution
The question is, will farmers really benefit? Until now there has been little research to back up the theory. The new renewable energy study comes from Princeton University aims to provide some answers.
The researchers were intrigued by the idea that the growth of wind and solar might help California reduce its reliance on hydropower. With less water for power generation, more water would be available for crop irrigation during periods of drought.
That’s just part of the equation. By using more surface water from rivers during droughts, farmers could reduce their use of pumped groundwater. That would provide the water table with more opportunities to replenish itself, leading to benefits across the board.
Groundwater depletion is not only a worry for farmers. It’s also a problem for entire regions dealing with the economic impacts of stress on water resources.
California’s groundwater takings policy was a virtual free-for-all until 2015, when state lawmakers established new rules and regulations. The Princeton research suggests that an aggressive timetable for wind and solar development would strengthen the new groundwater policy in addition to cutting the state’s carbon footprint.
Renewable Energy (Wind & Solar, That Is) To The Rescue
In essence, the researchers argue that policy makers should consider the value of water in agricultural use along with the value of reducing carbon when calculating the economics of new wind and solar projects.
The end result of such calculations, ideally (for wind and solar fans, that is), would be to create a financial platform that justifies accelerating the pace of wind and solar development at the expense of hydropower.
The researchers explain that “water allocation trade-offs between hydropower generation and irrigation use, and their future evolution, can be potentially solved by consideration of integrated management tools and the fast increase of low-carbon energy generation, such as solar and wind energy.”
They also point out that new technology is reducing the reliance on hydropower dams for energy storage:
“…energy systems are becoming less reliant on hydropower, as well as fossil fuels, especially for developed regions. Consequently, water used to drive turbines for hydropower generation can be saved for irrigation purposes to ensure food production, whilst reducing groundwater usage thereby increasing groundwater sustainability especially under drought.”
What About Fossil Fuels?
In arriving at their conclusion, the researchers noted that California is already on its way to reducing the role of hydropower in its energy profile.
Hydro’s long-term average share of electricity in California is 18%, but during a peak drought year of 2015 it fell to just 7%, thanks in part to the growth of wind and solar.
The bad news is that the increased use of natural gas has also helped California to offset its hydropower profile.
That brings up a whole ‘nother can of worms, namely, the amount of water used in fossil fuel operations.
Back in 2015 the US Geological Survey took stock of the amount of water used in mining operations, including oil and gas extraction as well as coal and other minerals. Even without any coal industry to speak of, California was still among the top four mining-related water users, clocking in at more than 200 million gallons daily. The other three were Nevada, Utah, and Texas.
Just another reason to keep those wind and solar projects humming through the pipeline.
CleanTechnica is reaching out to our friends over at the Union of Concerned Scientists for their insights about the Princeton study, so stay tuned for more on that.
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Image: “Using drought-prone California as a case study, a research team shows that increased solar and wind energy can reduce the reliance on hydropower, especially during drought,” by Egan Jimenez, Princeton University via Eurekalert.org.