Say that a restaurant offers “healthy, natural” chicken soup. How do you know what it means by “healthy” or “natural?” Farmers can cage chickens, feed them genetically-modified soy, wash butchered birds in antibiotics—and still call their chickens natural. Cooks can use lead-coated pots and chemically-fertilized vegetables–and still, legally, call the soup healthy.
“Healthy” and “natural” are marketing terms. Likewise, when corporations offer “clean,” “renewable” solar photovoltaic (PV) power, how do you know their definition of “clean” or “renewable?”
Now, with The Inflation Reduction Act granting $369 billion to subsidize homeowners and developers’ purchase of “renewables” like rooftop and utility-scale solar, must consumers considering these systems assess the technology themselves?
Questions and concepts
Assessing solar PVs starts with questions. Is our goal to reduce overall energy consumption and greenhouse gas emissions internationally—or just within a certain country or state? Do we aim to reduce extractions? Do we want to strengthen power grids’ resilience and/or to reduce some electric bills?
Like any products, solar PV systems need life cycle analysis (LCA) that includes their impacts from design to discard. A solar PV system’s phases include design, manufacturing (extraction and refining of ores, manufacturing chemicals, transport of raw materials, assembly, transport of the final product), operation, and discard or recycling. Assessments that neglect any of these phases are incomplete since energy used in manufacturing any device accounts for much more than the energy used to operate and discard it. For example, a laptop will consume 81% of its lifetime energy use before its end-user turns it on for the first time.
A solar calculator can estimate how much money you’ll save with a solar PV system; but it likely won’t include the system’s ecological impacts to your neighborhood, communities where the system was manufactured or its final (landfill?) station. Carbon calculators likely do not recognize that energy efficiency increases energy use, extractions, manufacturing and end-of-life waste: when a product’s efficiency increases, its price decreases and more people buy it. This leads to more energy use, mining and hazardous waste. 1
Another little-known truth: No agency monitors use of terms like “green,” “clean,” “carbon-neutral,” “net-zero-emitting” or “sustainable.” These are marketers’ terms—just like “healthy” soup.
Manufacturing
You know those white squares underneath a solar panel’s glass? They’re made from silicon, which is not available in nature in pure form. The process starts with transporting pure quartz gravel, pure carbon (i.e., Tar Sands’ petroleum coke) and moist wood to a smelter that is kept at 3000 degrees Fahrenheit for six or seven years at a time. Because smelters require steady delivery of electricity—or they could explode—they’re typically powered by natural gas, coal (fossil fuels) and/or nuclear power. Neither solar nor wind can power a smelter since they provide only intermittent power.2 The smelter “reduces” the silicon from the quartz to create metallurgical-grade silicon, which is not nearly pure enough for solar panels.
To produce 20,000 tons of polysilicon, a modern plant consumes up to 400 megawatts of continuous power per year (~175 MW/hours per ton of polysilicon)—drawing enough power as a city of 300,000 homes.3
The next two steps—making a cylindrical silicon ingot, then slicing it into solar-grade wafers—are also energy-intensive, toxic waste-emitting processes.4
Once formed, the wafers require “doping.” Dan Stih, a former process engineer in a semiconductor wafer fabrication facility, explains: “In a furnace, silicon wafers are doped with compounds such as (extremely toxic) boron tri-chloride and phosphine, a poisonous gas. High heat diffuses the phosphine and boron into the silicon.”
After many more steps, the wafers can then receive electric signals, the sun’s energy can activate the circuit, and the panel can generate electricity. Water used in this process is now hazardous. At its end-of-life, the panel itself is also hazardous.
To increase durability, transparency, UV-resistance, heat-resistance, mechanical strength, dirt-repellency and energy production, a solar panel’s frame, front sheet, back sheet and encapsulant5-9 (and batteries, if there are any10,11) each, typically, hold perfluorinated chemicals (PFAs).
PFAs do not break down in water, soil or our bodies.12-14 Studies show that exposure to “forever chemicals” may weaken immune systems, increase cholesterol levels, change liver enzymes, increase pregnant women’s risk of high blood pressure or pre-eclampsia, and increase risk of kidney or testicular cancer. While the fluorochemical industry claims that newer PFAS are safer, research shows that these chemicals are equally harmful.15
Do solar panels damaged by hail or tornadoes leak PFAs? Should people not eat vegetables grown near solar PV installations?
Recent reports claim that a handful of Chinese factories produce nearly half the world’s polysilicon—and that they use forced Uyghur labor. 16,17 Could consumers insist on fair labor practices for PV manufacturers?
Transporting solar PVs’ raw materials to factories (and the final products to consumers) requires cargo ships that use highly polluting bunker fuel. Does life cycle analysis of solar PV systems include these shipments’ ocean impacts?
While PV proponents might say that electricity powered by fracked natural gas, coal or nuclear power impacts ecosystems more than “renewables,” they don’t address the fact that manufacturers depend on fossil fuels to manufacture PVs. They don’t address the United Nations’ Environmental Program’s 2016 report: it noted that countries that invest heavily in “green” technologies—Sweden, Germany, Finland and the U.S.—rank environmentally sustainable on the UN’s index.18 China, the Democratic Republic of Congo and India—where ores are mined and smelted; where manufacturers make chemicals and dope silicon; where e-waste is discarded… these countries generate lots of CO2, toxic waste and worker hazards—and rank environmentally unsustainable.
If we need to reduce carbon emissions worldwide, why increase some countries’ emissions so that others can call themselves “carbon-neutral?”
Operation
On sunny days, solar PVs collect sunlight and generate energy best between 11am and 3pm. On cloudy days, they produce 10-25% of sunny-day energy. Meanwhile, households demand electricity mostly around dinnertime—well after solar panels generate it. Users who want electricity 24/7 therefore need backup power.
Ten percent of solar systems are backed up with battery storage. Making batteries requires extractions (i.e., lithium, cobalt, copper), chemicals and water. Batteries are expensive—and hazardous to manufacture and at disposal.19
About ninety percent of solar PV systems stay grid-connected. Backup for these households comes from whatever fossil fuel the utility uses.
Solar PVs can weaken grid stability: traditionally, to balance industrial and residential consumption, utilities asked residential customers to do energy-intensive activities at night or on weekends—when industrial demand decreases. Now, solar systems send so much electricity (during the day) to their utilities that utilities sometimes must pay others to take their excess.20
In 2021, to help balance day-time and night-time energy use, California told its e-vehicle owners to charge during the day.21
At the end of a sunny day, do solar PV systems increase or decrease grid resilience?
End-of-life waste
The vast majority of electronics’ toxic waste occurs during manufacturing. Still, end-of-life solar PV waste is significant—and growing. According to the International Renewable Energy Agency (IRENA), by the end of 2016, the world had generated about 250,000 metric tons of solar panel waste. That same year, IRENA projected that by 2050, the world could acquire 78 million metric tons of solar panel waste.22
Typically, solar panels contain lead, cadmium and toxins like PFAs. According to the Electric Power Research Institute, solar panels should not be disposed of in “regular” landfills since modules can break—and toxins can leach into the soil.23 Recycling solar panels—separating their materials for re-use—consumes substantial energy.
Other key issues
This paper has not covered:
- Since large solar arrays produce low-energy-density, they require massive amounts of acreage to supply industries (i.e., data centers) with sufficient power. At the Spotsylvania Energy Facility, 4500 acres of trees were removed and 1.6 million solar panels were installed to power nearby data centers. Who benefits from removing 4500 acres of CO2-absorbing trees?
- Large solar arrays that have no storage depend on the grid’s natural gas, coal, hydro or nuclear power for backup. Some large arrays rely on highly toxic battery electric storage systems (BESS).24 What are the consequences? What are the benefits?
- Solar PVs guzzle water during manufacturing and to remove dust for efficiency. When solar arrays cover fields that had absorbed water, the land’s ability to nourish microbial and plant life, sequester carbon, absorb and store more water is disturbed. Drought and flooding may result.
- All electrical equipment poses fire hazards. On a roof (with possibly flammable materials), solar panels increase electrical connections; if there is a fire and the panels are generating electricity, firefighters cannot turn off the panels. On a field, rodents chewing soy-based PVC can expose wires and lead to arcing. What if there’s dry vegetation nearby?
- When they convert the sun’s direct current to alternating current, solar PV systems “chop” the 50 or 60Hz cycle, exposing residents to potentially harmful electrical pollution.25
- China controls 70% of the rare-earth market—our dependence on it creates geo-political conflicts.26
- Extraction endangers fragile ecosystems like the Amazon.
- Demand for copper—used in solar panel wiring, cables and inverters—could exceed supply by 2025.
Solutions
Before investing, municipalities and individuals need life cycle analysis of a “renewable” system’s costs (including embedded carbon, energy, water and worker hazards) and benefits.
Restore the engineering principle that no technology is safe or ecologically sound until licensed experts who hold liability for their reports have certified the project’s safety and soundness.
Get a government agency to define and monitor terms like “sustainable,” “carbon-neutral,” “zero-emitting,” “renewable” and “green.”
Before buying a solar PV system, consumers should trace the supply chain of one of its substances.
Schools, businesses and households could commit to reducing energy use by three percent per month—and share with them learn.
Notes
1 The Jevons Paradox, first described in William Jevons’ 1862 book, The Coal Question.
2 Troszak, Thomas, “The hidden costs of solar photovoltaic power,” NATO Energy Security Centre of Excellence, No. 16., Nov. 2021.
3 Bruns, Adam, “Wacker Completes Dynamic Trio of Billion-Dollar Projects in Tennessee: ‘Project Bond’ cements the state’s clean energy leadership,” 2009.
4 Troszak, Thomas, Why Do We Burn Coal and Trees for Solar Panels?
5 Rojello Fernandez, Seth, C. Kwiatkowski, T. Bruton, Building a Better World: Eliminating Unnecessary PFAS in Building Materials, Green Science Policy Institute, 2021.
6 AiT Technology. (2015). Transparent Encapsulating PVDF Front Sheet - AI Technology, Inc. AiT Technology.
7 Terreau, C., De, J., & Jenkins, S. (2014). Encapsulation of solar cells (USPTO Patent). Google Patents.
8 Daikin. (2020a). Chemical Products UNIDYNE Repellents and Surface Modifiers Daikin America. Daikin America.
9 Daikin. (2020b). Renewable Green Energy Zero-Energy Fluoropolymers. Daikin America.
10 Arcella, V., Merlo, L., Pieri, R., Toniolo, P., Triulzi, F., & Apostolo, M. (2014). Fluoropolymers for Sustainable Energy. In D. Smith, S. Iacono, & S. Iyer (Eds.), Handbook of Fluoropolymer Science and Technology (pp. 393–412). Wiley Online Library.
11 Daikin. (2012). Business Review: Daikin Fluorochemical Products. In Chemwinfo.
12 Agency for Toxic Substances & Disease Registry. (2018). ATSDR - Toxicological Profile: Perfluoroalkyls. Agency for Toxic Substances & Disease Registry.
13 C8 Science Panel. (2012). C8 Probable Link Reports. C8 Science Panel.
14 National Toxicology Program. (2016). NTP Monograph Immunotoxicity Associated with Exposure to Perfluorooctanoic Acid or Perfluorooctane
Sulfonate. In the National Toxicology Program.
15 Gomis, M. I., Vestergren, R., Borg, D., & Cousins, I. T. (2018). Comparing the toxic potency in vivo of long chain perfluoroalkyl acids and fluorinated alternatives. Environment International, 113, 1–9.
16 Murtaugh, Dan, Colum Murphy and James Mayger, Secrecy and Abuse Claims Haunt China’s Solar Factories in Xinjiang, April 13, 2021.
17 Bloomberg News, Solar energy boom could worsen forced labor in China, group says, March 28, 2022.
18 Jason Hickel, The World’s Sustainable Development Goals Aren’t Sustainable, Sept. 30, 2020. Global Material Flows and Resource Productivity: Assessment Report for the UNEP International Resource Panel, 2016.
19 Klinger, PhD, Julie Michelle, Environmental Footprints of Rare Earth Mining Past and Present, Center for the Sustainable Separation of Metals, Feb. 22, 2021.
20 Penn, Ivan, California invested heavily in solar power. Now there’s so much that other states are sometimes paid to take it, LA Times, June 22, 2017.
21 Fujita, Akiko, California’s electrical grid has an EV problem, finance.yahoo.com, May 19, 2022.
22 Atasu, Atalay, et al., The Dark Side of Solar Power, Harvard Business Review, June 18, 2021.
23 Kisela, Rachel, California went big on rooftop solar. Now that’s a problem for landfills, LA Times, July 14, 2022.
24 Martin, Dr. Calvin Luther, BESS Bombs, Parts 1 & 2.
25 Johnson, Jeromy, The Dark Side of Solar, April 2017.
26 Cullinane, Danica, Rare earth stocks on the ASX: The Ultimate Guide, September 11, 2019.
Further Resources
Citizens for responsible solar.
Documentaries: Jeff Gibbs and Michael Moore’s Planet of the Humans, Julia Barnes’ Bright Green Lies, and Jean-Louis Perez and Guillaume Pitron’s The Price of Green Energy.
Jensen, Derrick, Lierre Keith and Max Wilbert, Bright Green Lies: How the Environmental Movement Lost Its Way and What We Can Do About It, Monkfish, 2021.
Owen, David, The Conundrum: How Scientific Innovation, Increased Efficiency, and Good Intentions Can Make Our Energy and Climate Problems Worse, Riverhead, 2011.
Rehbein, Jose A., et al., Renewable energy development threatens many globally important biodiversity areas, Global Change Biology, 4 March, 2020.
Smith, Olivia, The dark side of the sun: avoiding conflict over solar energy’s land and water demands, New Security Beat, 10.2.18.