Archive for March 5th, 2023
Tennessee was the state that prosecuted a teacher for teaching the theory of evolution
Tennessee is famous for prosecuting John Scopes for teaching the theory of evolution, now accepted as the bedrock foundation of biology. But — perhaps as one might expect, given its nature — Tennessee has learned nothing.
How to expand solar power without using precious land
Stephen Battersby writes at PNAS.org:
Land is a finite resource, facing huge demands from a growing population that clamors for living space and food. Farming, meanwhile, is beset by soil degradation, water shortages, plummeting biodiversity, and climate change.
So it’s unfortunate that solar power, an essential solution to climate change, should also be hungry for land. To generate as much energy as a conventional 1-gigawatt power station, an array of solar photovoltaic (PV) panels needs to cover about 80 square kilometers of land. Unsurprisingly, solar development faces increasingly organized resistance from many rural communities and activist groups, who see it as an enemy of farming.
Yet there’s no need for this confrontation. Properly designed solar installations can increase food harvests, reduce the need for irrigation, revive dying lakes, rescue pollinators, restore soils, and cool overheated humans—all while producing more power than conventional solar arrays.
That’s the promise of a wave of projects that aims to expand solar power without taking useful land out of commission. Symbiotic solar installations on farmland, lakes, and parking lots could enable solar to supply a large fraction of the world’s energy needs sooner than would otherwise be possible. “This can grease the skids for solar, by reducing conflict between food and energy,” says Greg Barron-Gafford, a plant ecologist at the University of Arizona.
These approaches still face a range of obstacles, including cost, convenience, and the need for collaboration between farmers and developers. But the signs are promising—researchers are developing symbiotic solar systems that are cheaper and more efficient, while governments are beginning to plow serious cash into the field. These efforts raise the possibility that symbiotic approaches might become commonplace.
Solar Farming
Solar power and farming often compete for the same precious land. It costs about $1 million to install a mile of electricity transmission lines, so most new solar power arrays are close to cities, where residents and industries need the power. But that puts solar installations in prime agricultural territory.
In 1982, researchers at the Fraunhofer Institute for Solar Energy (ISE) in Germany proposed a stunningly simple solution: set solar panels a few meters above the ground, and grow food underneath. Their original sketch shows angled panels with fairly large gaps in between, so the crops still get plenty of sunlight (1). This concept began to bear fruit in the early 2010s, with field trials in Japan and Europe. Japan now has about 3,000 farms with small solar installations set up on stilts, which are financially supported by government funding and known as solar sharing. In the United States and Europe, this idea is usually called agrivoltaics (AV), and it comes in a mouth-watering array of varieties.
The simplest approach is to plant grass under the panels and unleash some sheep. The United States already has more than 15,000 acres of solar grazing, including a huge 4,700-acre site at Topaz Solar Farm in California. The sheep gain shelter from the panels, and it saves on the cost of cutting the grass. With an eye on improving biodiversity, other projects plant native vegetation beneath their panels to support pollinating insects. This can also restore soils that have been depleted and compacted by decades of intensive farming, locking up carbon from the atmosphere. Both of these are low-maintenance options, and they work with panels set less than 1 meter above the ground, which keeps installation costs down.
Greater benefits can come from combining solar with food crops. The solar panels must be mounted higher up to allow workers and machinery to access the crops, making the setup more expensive. But this approach can help to offset those costs by boosting harvests.
In 2016, for example, Barron-Gafford’s team started an AV project growing cherry tomatoes, chiltepin peppers, and jalapeños—“things to make salsa, because if all else fails, you can still eat the science,” he says. The researchers found that the panels kept plants cooler during the day and warmer at night, and they held more moisture in the air. These less-stressed plants produced just as many jalapeños, twice the crop of tomatoes, and three times the amount of chiltepin peppers as those on a control plot (2). They also needed substantially less watering, a key benefit in a time of worsening water shortages around the world. Water evaporation from the plants even helped to cool the panels and increase electricity output.
Making Light Work
Some of the best crops for AV systems include root vegetables and leafy greens, which grow larger leaves in shady conditions. A US-wide study called InSPIRE (Innovative Solar Practices Integrated with Rural Economies and Ecosystems) has spent the past 7 years studying dozens of AV installations to provide a robust evidence base to guide crop selection, including what grows well under various climates and designs. “We had bits of AV starting to blossom in different parts of the country, but we don’t have time for academics to putz around in their own worlds; we need to work together,” says environmental scientist Jordan Macknick at the National Renewable Energy Laboratory (NREL) in Golden, Colorado, who leads the InSPIRE team.
The project’s first report, which came out in August, shows that details matter—some varieties . . .
US is averaging one chemical accident every two days
Carey Gillam reports in the Guardian:
Mike DeWine, the Ohio governor, recently lamented the toll taken on the residents of East Palestine after the toxic train derailment there, saying “no other community should have to go through this”.
But such accidents are happening with striking regularity. A Guardian analysis of data collected by the Environmental Protection Agency (EPA) and by non-profit groups that track chemical accidents in the US shows that accidental releases – be they through train derailments, truck crashes, pipeline ruptures or industrial plant leaks and spills – are happening consistently across the country.
By one estimate these incidents are occurring, on average, every two days.
“These kinds of hidden disasters happen far too frequently,” Mathy Stanislaus, who served as assistant administrator of the EPA’s office of land and emergency management during the Obama administration, told the Guardian. Stanislaus led programs focused on the cleanup of contaminated hazardous waste sites, chemical plant safety, oil spill prevention and emergency response.
In the first seven weeks of 2023 alone, there were more than 30 incidents recorded by the Coalition to Prevent Chemical Disasters, roughly one every day and a half. Last year the coalition recorded 188, up from 177 in 2021. The group has tallied more than 470 incidents since it started counting in April 2020.
The incidents logged by the coalition range widely in severity but each involves the accidental release of chemicals deemed to pose potential threats to human and environmental health.
In September, for instance, nine people were hospitalized and 300 evacuated in California after a spill of caustic materials at a recycling facility. In October, officials ordered residents to shelter in place after an explosion and fire at a petrochemical plant in Louisiana.
Among multiple incidents in December, a large pipeline ruptured in rural . . .
Later On 