Arguments
Solar and crop production research shows ‘multi-solving’ climate benefits
Posted on 6 December 2021 by Guest Author
This is a re-post from Yale Climate Connections by by Martín Bonzi and Sarah Spengeman
Stabilizing the climate demands a rapid transition to 100 percent carbon-free power, which will require large increases in solar power generation. In the U.S., the Biden administration has outlined a plan to power 40 percent of the U.S. power grid with solar energy by 2035.
Compared with agriculture and ranching, the land requirements of solar are quite small. Research from the National Renewable Energy Laboratory finds that just 0.6% of the country’s land mass would be needed to power the entire country with solar power. Still, utility-scale solar projects can require hundreds of acres, and new solar projects sometimes face resistance given competing needs for food-producing farmland or recreational space.
But new studies point to the multiple benefits of combining solar electricity generation with agricultural production. From water conservation to food production, habitat restoration, and local economic development, the research demonstrates that the “multi-solving” power of agrivoltaics (combining solar in concert with other agricultural land uses) can increase public support for solar development, offering an opportunity to avoid or resolve conflicts.
Saving water and energy while improving animal welfare
Finding sufficient water for food production in the western United States has always been challenging given the arid climate, but climate change-fueled droughts are making the situation worse. To get at this growing concern, University of Arizona researchers tested their own agrivoltaic system: They planted chiltepin pepper, jalapeño, and cherry tomatoes under a solar array and compared the results to a traditional, open-sky planting area for three months.
The researchers found the panels helped moderate ground temperatures, reducing water use and improving carbon uptake among the plants. Remarkably, food production doubled under the agrivoltaic system. And because water evaporation from the plants cooled the panels, the solar system itself generated 3% more electricity during the summer, showing how both food and solar production can perform better when done in collaboration.
Agrivoltaics can support plant production, but with what effects on animals? Pasture for animal grazing uses about one-fifth of all land in the U.S., much of it in the West, where natural solar resources are also the greatest, presenting a major opportunity for agrivoltaics. Researchers at the University of Oregon investigated the effects of installing solar arrays on active grazing land, comparing a traditional open pasture farm with the Rabbit Hills Solar Farm in Oregon, which combines sheep grazing and solar energy generation.
Sheep in the agrivoltaic system consumed the same or less water, as they spent a lot of time in the shade of the solar panels during the hottest months. While the pastures in the agrivoltaic system produced less grass, the nutrient quality and seed content was higher: As a result, lamb production was similar in both systems, but land productivity was much greater in the agrivoltaic farm.
In another study, in Texas, researchers found major environmental benefits when they evaluated the emissions and energy-use impacts of combining solar generation with pasture-fed rabbit farming. Compared with non-integrated conventional rabbit farming, the agrivoltaic rabbit farm used its own locally produced solar for energy, demanding 98.8% less fossil energy from the grid. In addition, the pasture-raised rabbits in the agrivoltaic system required no external feed, and the pasture did not need mowing, resulting in 98.5% fewer greenhouse gas emissions compared with conventional rabbit farming alone.
Overall, these two studies suggest that combining pastureland with solar generation would have no negative impact on animal productivity but would provide an opportunity to improve water conservation and animal welfare and offer steep cuts in emissions from farming operations and significant increases in land productivity.
Restoring pollinator habitat
Another study explores the roles of pollinating insects as a cornerstone of natural and agricultural ecosystems. These insects contribute to the reproduction of 75 percent of flowering plant species and 35 percent of crop species globally. But the number of pollinators has declined dramatically in recent years as a result of habitat loss and pesticide use, further aggravated by accelerating climate change – presenting a major threat to food security. Given that land underneath solar installations is often unused, filling the area below with habitat for pollinating insects could help protect these critical species, and researchers are examining this potential.
Researchers in a study of the Eagle Point Solar Plant in southwestern Oregon found that land used for solar arrays does indeed make excellent pollinator habitat and that pollinators were just as likely to visit flowers under shaded areas as they were in unshaded areas. In addition, the researchers found that the cooler, moister microclimate in the partially shaded areas under solar panels both increased floral growth and delayed flower blooming time. The delayed blooming is key for sustaining pollinator populations, as it can help support pollinators in the late summer when food is scarce but still needed for migration or winter storage.
Increasing public support
Although Americans overwhelmingly back renewable power, that support doesn’t always play out when a project is planned for one’s backyard, and local opposition can delay or even block proposed solar or wind installations. Still, the research shows people value the multi-benefits that agrivoltaics bring to their local communities. A survey of approximately 2,000 respondents in Michigan and Texas, for instance, found 81% were more likely to support solar development in their community if it combined energy and agriculture production.
Survey respondents said they preferred projects that provide economic opportunities for farmers and the local community, do not threaten local interests, and ensure fair distribution of economic benefits. These results suggest that solar projects that integrate other land uses in ways that directly address the local community’s needs are more likely to head off possible local opposition.
Tackling multiple problems with a single solution
Without a rapid buildout of new solar power generation, greenhouse gases won’t be cut in time to avoid the most dangerous consequences of climate change. But climate change is a threat-multiplier, worsening drought, food scarcity, and extinctions. An emerging body of research is demonstrating that agrivoltaics can help support the expansion of solar power while tackling other serious challenges and delivering additional benefits to surrounding communities. Agrivoltaics can also help shore-up public support, especially in rural areas, helping to accelerate the clean energy transition. With so much under threat from a fast-accelerating warming, these kinds of multi-solving projects will be key for both cutting emissions and for bolstering resilience.
Martín Bonzi is Program Associate with the Aspen Global Change Institute, and Sarah Spengeman, Ph.D. is Deputy Director of Communications with Energy Innovation LLC.
I wasn't sure where to start with the above essay, so much of it is grasping for straws. 0.6% of the land necessary to erect solar power grids, then employed for the reasons listed, is itself a discussion about nothing at all. We would be better off just planting trees on an equivalent area on the other side of town, or converting cattle grazing land to riparian. As far as raising rabbit goes, current nutritional science has proven that eating rabbit is equivalent to eating rats, insofar as nutrient values are concerned. There are no nutrient values in rabbit meat...not for humans. Regarding bee habits, we beekeepers know that bees enjoy sunshine and love the floodplain of rivers as forage areas, although they will harvest the nectar of flowering trees, especially tulipfera species which cannot grow under a solar panel. My apologies, I could go on about several other points made in this post, but my essay is long enough as it is. ...someone else's turn.
Swampfox could you please provide proof of your assertion that rabbit meat contains low nutritional value for humans, because 1) it defies basic commonsense and 2) a quick google search shows a vast quantity of credible publications stating rabbit meat has a particularly high nutritional value for humans. The first three hits are below:
www.agriculturejournals.cz/publicFiles/22711.pdf
www.livestrong.com/article/342037-nutrition-in-rabbit-meat/
foodstruct.com/compare/rabbit-meat-vs-chicken-meat
Go to literature not published by commercial agricultural interests. Rabbit meat is all protein. Routine periodic consumption of this animal causes protein poisoning which can and eventually will kill you. In regions of the world where food options are scarce, rabbit is a consumption item because it is plentiful since rabbits breed like rabbits (humor intended). Nutritionists in First World countries do not recommend eating rabbit because they provide no fat, which is required in the human diet. Rats are rodents, of course, as are rabbits. We should not eat rats either, for much the same reason: protein poisoning.
Perhaps it is my use of the term: nutritional value. While protein can be called a nutrient because it is used by the body to build muscle structures, human bodies need fats for energy production. Lipids are 1 of 6 essential components in animal life forms and are essential in an every-day diet. Protein is needed, of course, but in infrequent amounts. Animal organisms can do without protein for extended periods (like starving prisoners of war) but fat intake is a daily dietary need for humans.
Swampfox
"Rabbit meat is all protein."
Wrong. You cite no specific source for this with an internet link. I gave you sources with links stating rabbit meant contains fat and one was a nutrionist. Other souces say much the same. Rabbit contains approximately 5.6 grams fat per 100 g about the same as a lean cut of chicken or pork.
Yes the human body needs fats and more than a rabbit can provide alone, but nobody is suggesting people in a place like America live on a diet exclusively of rabbit. You would eat other more fat rich meats as well, or get fats from other sources. Although to be honest I tried rabbit once and didn't much like it.
nigelj
The 5.6 grams of fat per 100g of "rabbit" is a value arrived at by the rabbit-raising industry. The location of the majority of this "fat" is the rabbit's brain, which is not likely to be served to humans as "food". Yes, I think it unlikely that First World countries would "do a lot of rabbit", but these critters are still "rodentia", and unlikely to gain any more market value than they ever have in First World countries. Still, the risk of protein poisoning from rabbit meat is a caution most nutritionists voice. This might mean rabbits are best left as the nuisance in nature, they and their relatives, the rats, have been since the dawn of civilization.
Since I don't have time, at present, to go out and look for the peer reviewed source you and SkepSci require for conducting dialog on this site, I withdraw my allegations as "un-evidenced".
Regards,
Swampy
nigel
One more quick thing. As you probably are aware, an animal, generally, just won't eat anything. Certainly, coprophagic organisms like domestic dogs are fairly happy eating other dog's excrement, but even here, not all dogs are "big" on foreign excrement and very few eat their own waste. Nature seems to have a sort of guard against an animal eating a certain substance...and some say such discrimination is a survival instinct.
Your particular experience with rabbit meat is one shared by many people...yuck! To speculate, to develop a hypothesis, to investigate the evidence and to formulate a testable theory about a "natural" safeguard against a "food" that a particular organism should consume or avoid could be a key to longevity. Why do some "turtles" live so long. Why do humans live much shorter lives than their telomeres might otherwise predict? Food (ingestion) choices? Is "rabbit" really unfit for human consumption?
Swampfox @6 & 7. Thanks. You are making more sense now and it does raise questions about whether rabbit farming is of any real use. Just dont make sweeping claims that rabbit meat is all protein when there is some fat, although a quick check shows its very little about 2 grams per 100 grams. You are right most appears to be in the brain, and I can assure you under no circumstances apart from extreme starvation would I be eating rabbit brains.
Rabbit meat having only 2 g of fat per 100 g of meat sounds like an excellent meat as long as the consumer is aware that they are getting very little fat with the meat. The low fat content means that even if all of it is harmful fat there is less harmful fat than many other meat options.
The following reasonably reliable resource (Canada's Government of Northwest Territories) would appear to contradict the claim that rabbit meat is a poor source of nutrition.
And this Washington Post article "From fish to bacon, a ranking of animal proteins in order of healthfulness" presents the case for the benefits of low fat content in meat (get healthier fat from other sources or eat the meat with lower content of harmful fat and higher content of helpful fats.
An important point is that it is wasteful to eat more than 4 oz (100 g) of meat in a meal. Many sources indicate that even a high performance athlete's digestion will only extract the protein benefit from 4 oz of meat. Many sources indicate the body will only process 30 g of protein from a meal. And 3 to 4 oz servings of meat contain 30 g of protein (100 g of rabbit meat contains 30 g of protein).
Also, nutrition Guides call a meat serving 3 oz. And, aligned with what swampfoxh points out, the Washington Post article refers to research indicating that "... consuming just two to four servings per month of fish and two to four servings per month of poultry can provide benefits ...".