Climate Break

What is Solar Grazing?

The deployment of utility scale solar has often required clearing vegetation and then using fossil-fuel-powered mowers or toxic herbicides to prevent overgrowth. To reduce these harms, solar grazing is a dual land use approach where livestock is taken to solar farms to manage the vegetation that can grow and interfere with the panels. Solar grazing reduces maintenance emissions, provides a revenue stream for local ranchers, and promotes soil health.

Why it Works: Sheep

Solar grazing is a type of targeted grazing, which is, “the controlled application of specific livestock at a designated season, duration, and intensity to achieve specific landscape and vegetation management goals”. Those goals often include weed control, fire risk reduction, and wildlife habitat enhancement. Solar grazing specifically refers to livestock grazing on solar farms, or, under and around solar arrays. According to the American Solar Grazing Association (ASGA), other terms associated with solar grazing include agrivoltaics (the co-location of agriculture and solar), agrisolar, agri-pv, or rangevoltaics. One grazier compares solar grazing to silvopasture - or, grazing under trees - “Just with metal trees”.

Sheep have been found to be an excellent match for the needs of solar grazing. Sheep are nimble and can work around solar installments, eliminating work that, without re-designing or raising solar panels, can be difficult for humans. The benefits of solar grazing extend beyond vegetation management: sheep have been measured to have lower body temperatures, both in their wool and skin, when they’re shaded by solar panels. Additionally, forage quality and moisture content are higher in the shade where water in the soil evaporates more slowly. Sheep have been shown to drink less water during solar grazing, which reduces water needs for graziers. Solar grazing also eliminates competition for land use between solar developers and graziers.

What’s Left to Learn

Solar grazing has been expanding across the country for the last decade; however, long-term studies on the effects of grazing on biotic and abiotic factors - as well as changes in cost over time - have not been widely conducted. One of the highest costs in solar grazing is transportation and logistics, so in places like the US’s Northeast where most solar farms are around 11 acres, moving sheep makes grazing less affordable. In regions with large or interconnected farms, that cost is reduced; Stacie reports that many sheep are born and live out their lives on one farm. Solar grazing is often viewed as just “mowing with sheep” - not as an active agricultural practice. The American Farmland Trust emphasizes that, on the contrary, “It’s a way to grow food, build soil, create habitat, and generate renewable energy at once.”

Stacie’s Points

Stacie emphasizes that grazing - even in areas where animals have to be rotated between sites - contributes less fossil fuel emissions than mowers that run on diesel. Mowers and weed-whackers have other side effects: blades have a tendency to “throw” rocks, or pick up and eject rocks, which can damage panels and add costs to operation. Also, using any machine powered by combustion increases fire risk.

There’s a demographic shift supported by solar grazing. Often, the greatest financial hurdle to a grazing operation is buying or leasing pasture; for young people who won’t inherit pastureland, solar grazing lowers the barrier to entering the industry. Stacie says that polling done by ASGA shows a lower average age of participants compared to the national average, which sits around 65. Also, a greater proportion of women are involved. Another upside: solar graziers are contracted by solar farms - meaning, instead of paying to lease or buy land, they’re being paid for their service - which adds economic opportunity. On the climate side, Stacie underscores improvement in overall soil health, but especially carbon sequestration. The use of agrivoltaics tends to improve public acceptance of large-scale solar, a key strategy for reducing the country’s dependence on fossil fuels.

About our Guest

Stacie Peterson is the Executive Director of the American Solar Grazing Association. She was a developer of the AgriSolar Clearinghouse for the Department of Energy and the Director of Energy Programs at the National Center for Appropriate Technology. Her environmental research includes the development of a protocol for domestic dogs to serve as bioindicators of metal contamination and cleanup efficacy.

Resources

Society for Rangeland Management, Targeted Grazing

Fonseca et al, Solar Shade on Sheep

American Farmland Trust, Grazing Between the Panels

Andrew et al, Sheep grazing as sustainable vegetation management for solar energy

For a transcript of this episode, visit https://climatebreak.org/grazing-livestock-on-solar-farms-with-stacie-peterson/

Why Sodium?

The global transition to renewable energy has accelerated the global development of lithium-ion batteries, but the mining and processing of its materials can be harmful to workers, local communities, and the environment. Sodium has a recently emerged as a potentially cheaper and more environmentally friendly alternative that could revolutionize battery storage systems. Dr. Shirley Meng is one of the scientists leading the way in this field, spearheading the creation of the world's first anode-free sodium solid-state battery.

Diving Deeper

Dr. Meng’s batteries have three key qualities: they are anode-free, sodium based, and solid-state. Though other researchers have developed batteries with similar characteristics, this is the first time all three have been combined.

Most batteries consist of three main parts: a cathode, anode, and electrolyte. The cathode is the positive pole, the anode is the negative pole, and the electrolyte is the material between the poles. As explained by the MIT School of Engineering, when a battery is connected to an external circuit, electrons move through the circuit, while simultaneously ions move through the electrolyte. The anode in a standard battery stores ions, while an anode-free battery starts out with no active anode material—the ions come entirely from the cathode.

According to laser tech company Laserax, there is one key difference between Lithium-ion Batteries (LIBs) and Solid State Batteries (SSBs): the electrolyte material. In an LIB, this is a liquid, typically liquid salt dissolved in an organic solvent, which is highly flammable. In an SSB, this liquid is replaced by a solid electrolyte. Dr. Meng calls the electrolyte in her team’s batteries the “magic salt” because it’s primarily made out of sodium chloride - the same chemical as table salt. By supplementing the magic salt with other chemicals like oxygen, yttrium, and zirconia, an ion-conducting electrolyte can be formed.

The Pros and Cons

Dr. Meng’s batteries use sodium in place of the lithium in LIBs. Lithium and other LIB components can only be mined in particular regions, and production - besides being deleterious to the environment - is tightly controlled by a handful of powerful countries. Sodium, on the other hand, is predicted to be about 1200 times more plentiful than lithium in the earth’s crust, and can be accessed from other sources like sea water.

Anode-free batteries are often lighter, cheaper, and more energy-dense than similarly capable standard batteries. However, they can be harder to manufacture and can have shorter lifetimes. As advances are made by other researchers working on alternate battery structures, these challenges will likely be overcome, as have similar difficulties with LIBs. Dr. Meng’s batteries operate best in the lab at low external temperatures, which fills a gap in the battery market in extremely cold climates; however, scalability and widespread use demands that batteries function in a wide temperature range.

Solid-state batteries also come with a range of benefits and challenges. Besides being less flammable, they can have faster charging, higher energy capacity, and longer lifetimes compared to LIBs. However, they are susceptible to the formation of dendrites - or, tree-like metallic structures on the anode - which form during charging and can cause short circuits. Solid electrolytes are prone to cracking under mechanical stress, both in manufacturing and use. Like anode-free batteries and other cutting edge battery tech, SSBs have a long way to go in terms of scalability, but show promise in the future of battery development.

Dr. Meng’s Take

Dr. Meng emphasizes that Sodium-ion battery technology is not new - research began back in the 1960s, but was outpaced by lithium-ion research, which at the time showed better results. Additionally, sodium batteries aren’t necessarily a replacement for lithium batteries, but rather a complementary technology that many companies will be able to produce without much capital investment. With the combination of these battery technologies, there is potential to moderate the cost of electricity at peak use times. Dr. Meng predicts that sodium-ion batteries may be able to compete with lithium-ion and lead-acid batteries in the next five years, and suggests that until then, costly but compact lithium batteries might be used in mobile applications, like computers, while sodium batteries - which for now are heavier - can be used for stationary purposes, like grid storage. Overall, she feels that it's “critical that all of us… stop temperature rise” - and sodium-ion batteries are a key step in the plan.

About our guest

Dr. Shirley Meng is the Liew Family Professor in Molecular Engineering at the Pritzker School of Molecular Engineering at the University of Chicago. She is also the Distinguished University Professor and Vice President (Industry) at Nanyang Technological University (NTU), Singapore. She directs the Energy Storage Research Alliance and is the principal investigator of the Laboratory for Energy Storage and Conversion (LESC) at UCSD. Her research focuses primarily on energy storage materials and systems – including rechargeable batteries and grid-scale storage for renewable energy.

Resources

UChicago, Team Develops Battery

Nature Energy, Design principles for enabling an anode-free sodium all-solid-state battery

LESC, Recent news

Physics Today, Solid State Batteries - Hype, Hopes, and Hurdles

Chemical Review, Anode-Free Batteries

For a transcript of this episode, visit https://climatebreak.org/the-future-of-battery-storage-with-dr-shirley-meng/

Introduction

Mozzarella accounts for over 30% of all cheese produced in the U.S., more than any other variety. So when New Culture, a San Francisco-based food technology company, set out to remake vegan cheese, they started with the pizza topping millions of Americans know and love. New Culture, co-founded by guest Matt Gibson, relies on fermentation to make animal-free cheese that melts, stretches, and tastes like the real thing. Crucially, this process cuts down on the emissions, land, and water dairy farming requires.

Background

Dairy production is a large driver of climate change. According to the BBC, cheese has the third-largest agricultural carbon footprint, after lamb and beef. Methane released by cows, sheep, and goats is a major contributor, along with the land and water needed to raise the animals. The process of cheesemaking multiplies this carbon footprint: it takes roughly ten pounds of milk to produce a single pound of cheese, meaning the carbon emissions of cheese are concentrated tenfold.

New Culture sidesteps both livestock and the plant-based substitutes that have tried to replace them by manufacturing casein– the protein responsible for cheese’s stretch and gooeyness. As Gibson explains, the company trains microbes to produce casein inside fermentation tanks, similar to the process used to brew beer. The microbes feed on sugars to produce casein, and that protein is then combined with plant-based fats to create the finished cheese. This method, known as precision fermentation, dates back to the 1970s, when researchers first used E. coli to produce human insulin.

Advantages

According to Gibson, switching from dairy to New Culture’s cheese cuts greenhouse gas emissions by roughly 86%, with a 97% reduction in land use and a 98% reduction in water use.

Perhaps equally as important, New Culture doesn’t ask consumers to compromise on taste or texture. The manufactured casein is molecularly identical to what’s found in dairy milk, meaning that the cheese melts the way people expect. This is something most conventional plant-based cheeses, which lack casein entirely, have not been able to replicate. The switch from dairy cheese to an alternative, then, is now potentially more palatable.

Drawbacks and Critiques

Producing precision-fermented proteins is significantly more expensive than regular dairy products. Gibson acknowledges this, explaining that dairy is a heavily subsidized industry, and New Culture’s casein protein is the most expensive part of its cheese. The company has had to engineer ways to use less protein per product without sacrificing quality to stay competitive. He also points to the challenge of limited fermentation tanks and infrastructure.

And it’s worth noting that the same trait that makes New Culture’s cheese taste like the real thing also carries a drawback. Because its casein is identical to the casein found in ruminant milk, someone with a milk allergy would still react to the cheese, even though no animal was involved in making it. This distinction could complicate how the product gets marketed and understood, since “animal-free” doesn’t necessarily equate to “dairy-free.”

The Guest’s Take

Gibson believes that “taste is king in the food world,” and because New Culture’s cheese is “indistinguishable to dairy cheese,” consumers aren’t giving anything up on the experience. He’s hopeful that as New Culture grows, costs will lower and its products will be adopted by mass-market restaurant chains where climate impact could be the greatest. For now, you can get a taste of New Culture mozzarella at partner restaurants like Pizzeria Mozza in LA.

About the Guest

Matt Gibson is the Co-Founder and Chief Executive Officer of New Culture. He holds a Bachelor of Science in genetics and microbiology from the University of Auckland in his native New Zealand. Before co-founding New Culture, Gibson went vegan out of concern for the environmental and animal welfare impacts of dairy production.

Other Resources & Further Reading

New Culture Website: New Culture

The Good Food Institute Europe: The History of Precision Fermentation

Vegpreneur: Matt Gibson’s Biography

For a transcript of this episode, visit https://climatebreak.org/making-cheese-with-microbes-with-matt-gibson/

Introduction

As California works to reduce greenhouse gas emissions from buildings, the transition to energy-efficient homes is an important opportunity for climate careers. The Rising Sun Center for Opportunity, a California-based nonprofit managed by Julia Hatton, helps address challenges faced by those in underserved communities when it comes to job training. Through hands-on programs, participants can gain valuable skills as they work to improve green buildings.

Background

Buildings account for over 40% of the global energy consumption and carbon emissions, making improvements to the energy and water efficiency of local homes an important part of climate strategy. As a result, the transition to clean energy creates a high demand for workers trained in energy efficiency and green construction—and there is a global shortage of workers with the applicable skills.

The Rising Sun Center for Opportunity assists not only with the immediate need, but also in building career pathways focused on long-term climate resilience. By employing young people from low-income backgrounds in the Bay and Central California, this nonprofit works as a launchpad for future climate action.

Advantages

Climate job training addresses both economic and environmental challenges simultaneously. Participants gain practical skills to help them enter the green industry, while households can receive services that save energy and water.

The hands-on approach that the Rising Sun Center for Opportunity utilizes furthers this endeavor, especially with the focus it has on leveling the playing field. With programs specializing in preparing youth, women, and individuals in reentry, a diverse range of participants can work directly in homes and communities. This provides immediate climate benefits to recipients of service, while workers gain experience in real-world projects that equip them with skills necessary for a long-term career.

Drawbacks and Critiques

Some contend that climate job training doesn’t always translate into long-term climate employment. Although the Rising Sun Center for Opportunity may provide an efficient starting point, participants are not guaranteed a green career, especially if employers require other additional experiences or skills.

There is also a need to ensure that the climate transition doesn’t just create jobs; it should also help establish economic power for those who have been marginalized from careers, as Hatton emphasizes. Although the Rising Sun Center for Opportunity aims to coordinate efforts from a wide group of historically disadvantaged communities, it’s crucial that efforts translate into real impact.

The Guest’s Take

Ms. Julia Hatton believes that investment in workers in green jobs is crucial to advance response to climate change. Rather than identifying job creation and reducing emissions as separate goals, Hatton sees potential in merging and combating both actions at once: by allowing them to reinforce each other.

About the Guest

Ms. Julia Hatton is the President & Chief Executive Officer at Rising Sun Center for Opportunity, committed to climate job training for underserved communities to lead climate action. She takes charge in leading innovation in the workforce and climate sector alike.

Other Resources & Further Reading

Rising Sun Center for Opportunity Website: Rising Sun

ScienceDirect: Energy-related carbon emissions in the building sector

Green Jobs Network: Climate Job Training

California Climate Investments: Workforce Development

For a transcript of this episode, please visit https://climatebreak.org/building-a-climate-workforce-with-julia-hatton/

The Global Transition

As the global transition to clean energy accelerates, scaling solar infrastructure has emerged as one of the most critical pathways to achieving a net-zero future. However, this rapid buildout could bring an increasingly large amount of waste as solar panels reach their end of life. To avoid this, recycling offers a dual climate solution: it significantly reduces the greenhouse gas emissions associated with primary mining and provides a supply of pre-refined, low-carbon materials that can be used to make new panels. 

The Role of Solar Panels

Transitioning away from fossil fuels and achieving net-zero carbon emissions at a global scale requires rapid deployment of renewable technologies. For solar energy specifically, the amount of solar infrastructure needed on Earth to meet climate goals is about 16 times what has already been built. This buildout demands large quantities of raw materials, including glass, silica sand, silver, copper, and aluminum. While these resources are traditionally mined from the Earth, they can also be recovered directly from solar panels once they reach their end-of-life.

Extracting and processing raw materials for solar panels through primary mining is resource-intensive, and recycling those materials significantly reduces the panels’ manufacturing emissions. Similarly, integrating recycled solar glass cullet into manufacturing lowers furnace operating temperatures, cutting energy consumption by 2.5% to 3% for every 10% of cullet added and reducing the overall energy and emissions needed to produce new glass.

If solar panels are taken to traditional e-waste recycling facilities, these sites typically rely on bulk shredding, a process that destroys material purity and scatters valuable metals. In contrast, the solar recycling process from SOLARCYCLE uses a step-by-step “reverse manufacturing” sequence in which the company strips away the junction box, removes the aluminum frame, and isolates the specialized glass to recover up to 97% of a panel’s material value. Furthermore, because solar manufacturing has evolved to generate more energy using fewer materials, the elements recovered from decommissioned panels can be the basis to build newer, higher-efficiency arrays that generate even more clean power.

The Impact on Energy and Raw Materials

Solar panel recycling requires dramatically less energy input, potentially avoiding up to 95% of the CO2 emissions and 95% of the energy needed to mine and process raw aluminum for new solar panels. What’s more, this technology can recover up to 99% or more of key materials like glass and metals.

Likewise, because this solution recovers critical resources like silver and copper from existing infrastructure, the technology can be used to mine materials from what has already been produced and collected rather than extracting new minerals from the Earth. This means the technology has the potential to eliminate up to 25% of manufacturing emissions for specialized solar glass, while diverting toxic chemicals like lead and cadmium away from landfills to protect environmental and human health.

Challenges: Recyclability and Economics 

Currently,  panels have not been designed for recyclability, making the process of separating their tightly sealed layers a technical challenge. Because solar manufacturers operate on very thin or negative profit margins, they have rarely prioritized design-for-recyclability features, leaving decades of panels that will need specialized, intensive processing when they decommission. Scaling this technology also presents operational challenges because, while recycling thousands of panels is manageable, processing the millions of units at scale will require tooling that a supporting industry cannot yet provide.

Solar panel recycling currently struggles to compete economically with traditional waste disposal depending on local geography. In countries like the United States, landfill remains the cheaper option, creating a financial gap that can deter asset owners from recycling the panels. Moreover, the process cannot yet achieve a fully circular loop for all components. Certain materials, like thermoset plastics, are unrecyclable and must be diverted to waste-to-energy processes. Finally, the industry faces regulatory risks from “sham recycling”, where bad actors take upfront payments but fail to manage the materials properly, creating an environmental hazard by exposing toxic lead or cadmium to the soil.

The Guest’s Take

Pablo Dias sees solar panel recycling as an essential part of the energy transition. For him, this process closes the loop on a true circular economy by allowing discarded panels to be mined for valuable resources like aluminum, silver, and copper instead of extracting raw materials from the Earth. This is part of a broader vision for a waste-free solar industry, turning end-of-life solar panels into a tool to drastically reduce the industry’s emissions and eliminate the environmental and social risks of heavy metal leaching.

About the Guest

Dr. Pablo Dias is the Co-Founder and Chief Technology Officer (CTO) of SOLARCYCLE, a recycling platform designed to build a circular economy for the solar industry. 

Further Reading

SOLARCYCLE

Resources on Solar Panel Recycling (SOLARCYCLE)

ScienceDirect: High yield, low cost, environmentally friendly process to recycle silicon solar panels: Technical, economic and environmental feasibility assessment

Wiley Online Library: Recycling Crystalline Silicon Photovoltaic Modules

Grist: What happens when solar panels wear out?

Personal Website – Pablo Dias

For a transcript of this episode, visit https://climatebreak.org/recycling-solar-panels-with-pablo-dias/