- The rapid adoption of solar home systems in Malawi is producing a matching increase in the use of lead-acid batteries.
- These batteries have a relatively short lifespan, especially when used with photovoltaic systems, and informal recycling processes release toxic lead and acid into the environment.
- There are more durable, less toxic batteries available, but they cost more.
- Malawi and other countries need better regulation and recycling infrastructure to ensure the benefits of small solar systems are not accompanied by environmental harms.
BLANTYRE, Malawi — On Lagson Gumbo’s side of the stream, BCA is a slum. Running parallel to the trickle of murky water is a narrow, dusty street lined with small, unplastered houses and shops trading in groceries, cheap alcohol and artisan services for residents of this crowded sector of Malawi’s principal commercial city, Blantyre.
On the stream’s other bank is an affluent neighborhood with the same name. In the wealthy BCA, Blantyre’s City Council provides waste collection services, removing rubbish to a site on the city’s outskirts. It’s an open landfill where people from low-income settlements scavenge for whatever they find worth for reuse or sale.
On the side where Gumbo lives and works, there’s no formal waste management. Residents dump rubbish from homes and shops into the stream. Kitchen waste and used nappies, old tires and plastic bottles and carrier bags get thrown into gullies and any other unoccupied spaces nearby. There are also batteries.
At his makeshift workshop, Gumbo sorts through metal plates he has extracted from expired lead-acid batteries. Before him is a smoldering charcoal stove and a plastic bag filled with pellets of lead — also extracted from batteries.
He puts the lead in a small tin container, pours acid over it and sets it on the stove to heat.
“These pieces were positive cells in the batteries,” he says, gesturing to the plates he’s laid out on a small worktable. “When a battery stops functioning, it is not the negative electrodes that have expired. It is the positives. So we remove the positive cells, fix them and restore the battery to life.”
Gumbo disposes of the scrap metal and broken battery casings wherever he can.
“Whatever we cannot recycle or reuse or resell, we dispose of it in spots around the area,” he says. “We used to burn it, but we stopped because, as you can see, we are too crowded. The smell can be too strong sometimes and we fear a house can catch fire.”
Gumbo learned his trade from his uncle. He is among scores of self-made technicians established in rural trading centers and high-density settlements across Malawi who are re-manufacturing expired lead-acid batteries. Gumbo and two others in BCA used to process mostly dead car batteries, but over the past 10 years, they have received a poisoned windfall: growing numbers of batteries from off-grid solar systems batteries.
In 2022, Christopher Kinally, a researcher in toxic environmental pollution and global health, and colleagues at the University of Manchester, U.K., wrote that batteries are the component of PV systems most likely to fail. Lead-acid batteries, often preferred because they’re cheap, are particularly prone to failure when discharged below 50% of capacity as frequently happens with solar home systems.
This results in rapid accumulation of waste. In further research published in the journal Applied Energy in 2024, Kinally and team studied what happens to this waste in the absence of safe, formal recycling or disposal.
They found that informal re-manufacturers like Gumbo are releasing potentially lethal amounts of lead into the environment even from a single battery.
Previous studies have identified informal recycling of lead-acid batteries as an important source of contamination in Africa. But no research had attempted to quantify the environmental impacts of informal waste and e-waste disposal practices.
Kinally’s work evaluated the lifespan of batteries used in small home solar systems in Malawi’s capital city, Lilongwe, and assessed collection of materials through the informal scrap market, open dumping and burning of battery waste material and the informal recycling processes.
The scientists describe how recyclers melt lead scrap, crush positive battery plates and make improvised cells. They also noted how any unwanted detritus then finds its way into the local environment.
“A significant amount of lead was lost to the environment as dust or shrapnel from the moment the degraded lead cells were removed from the battery casing and throughout every stage in the recycling process,” they write.
“Achieving extended battery lifetimes of three years combined with formal recycling can mitigate the toxicity of the current waste management practices and avoid excessive greenhouse gas emissions from these practices,” the study says.
Growing market, growing problem
With electricity access across Sub-Saharan Africa at roughly 42%, the region is a rapidly expanding market for cheap, off-grid solar systems. In Malawi, three quarters of the population — over 15 million people — live in homes that aren’t connected to the main electricity grid, according to the Malawi Renewable Energy Strategy for the period 2017-30.
Governments, businesses and individuals are all investing in solar systems. In the case of Malawi, alongside private sector and NGO projects, distribution of solar systems is among the initiatives under the Malawi Rural Electrification Programme (MAREP) implemented by the Malawi government.
According to figures from the Ministry of Finance, the government and off-grid solar companies installed standalone solar home systems for 13,000 households in 2023, benefiting an estimated 57,000 people.
As rollout of off-grid solar systems rises, Gumbo’s business is booming. When he started refurbishing lead-acid batteries 14 years ago, he says, the batteries all came from cars and motorcycles. But in the last 10 years, he has seen a surge in solar system batteries at his shop.
He says he receives four or five each week, and that he makes a profit equivalent to a bit less than $3 from each one, “depending on the complexity of the work.”
The key tools of his open-air factory are basic: knives, pliers and screwdrivers to split batteries open, a blade of metal for scraping and scooping lead out of the batteries and a charcoal stove for smelting parts and heating the lead.
According to the study, around 48% of the lead content of a battery is released into the environment by these informal lead-acid battery re-manufacturing processes creating “severe localized health risks and potential adverse effects on environment.” The authors say off-grid systems present a pollution challenge in Africa particularly because the market is not regulated to enforce high standards of products being distributed.
Secondly, marketing of the products is aimed at low-income communities who can only afford cheap — in many cases, counterfeit — equipment with a short lifespan. In addition, many users have inadequate knowledge of design, installation and operation of these systems.
While electrical and electronic waste is accumulating, few countries in the region have physical or legislative infrastructure to manage it. South Africa and Kenya are among the exceptions with lead-acid battery recycling facilities that limit pollution.
Kinally says lead-acid batteries are the most toxic component of photovoltaic systems, compared to the panels themselves or other parts that have long lifetimes. He says that, while there is currently a lack of adequate research to determine the full scale of the impact that lead contamination has on living organisms in surrounding ecosystems in Lilongwe and elsewhere, the bioaccumulation of lead in the food chain is a significant concern.
But, he adds, with safe recycling facilities for lead-acid or other batteries in place, photovoltaic systems could be a promising way to increase access to electricity in Africa. “The market for photovoltaic systems is already very established and embedded into societies across the region. Therefore, the focus should be to support the solar market with the regulation and waste management infrastructure necessary to prevent environmental and health burdens,” he says.
Shanil Samarakoon, a researcher working on energy and environmental markets at the University of New South Wales in Australia and who’s not part of Kinally’s study, says the study findings highlight “the broader energy injustice of placing deep reliance on households to provision their own sources of electricity”.
“Within this context, the environmental harms that flow on from the necessary mass adoption of these products — to alleviate energy poverty — represent a form of injustice. One that has negative impacts across species and generations,” says Samarakoon, who has also conducted studies in Africa, including Malawi, on off-grid solar systems.
Ideally, subsidizing larger and more durable systems for household use would translate into greater social impact in productive uses of solar power beyond lighting and phone charging, he says. This would also help reduce waste that is accumulated through the replacement rate of successive small-scale solar products.
“However, this form of transition planning appears to grate against the impulses of market-driven solutions, which trade on increasing margins and sales volumes,” says Samarakoon.
He suggests increased investment in public education on the use and maintenance of solar systems, “as well as nurturing a repair economy to provide livelihoods for technicians as well as extend the productive life of products which would reduce waste accumulation.”
Banner image: Mounting a solar panel in Malawi. Image by Jon Strand via Wikimedia Commons (CC BY-SA 4.0).
In Malawi, a rural community shines bright with 100% solar power milestone
Citations:
Kinally, C., Antonanzas-Torres, F., Podd, F., & Gallego-Schmid, A. (2024). Life cycle assessment of solar home system informal waste management practices in Malawi. Applied Energy, 364, 123190. doi:10.1016/j.apenergy.2024.123190
Kinally, C., Antonanzas-Torres, F., Podd, F., & Gallego-Schmid, A. (2022). Off-grid solar waste in sub-Saharan Africa: Market dynamics, barriers to sustainability, and circular economy solutions. Energy for Sustainable Development, 70, 415-429. doi:10.1016/j.esd.2022.08.014
Feedback: Use this form to send a message to the author of this post. If you want to post a public comment, you can do that at the bottom of the page.
Credits
