From trash to power: How to tap energy from Africa’s garbage dumps
NEW research on garbage dumps in 44 sub-Saharan African countries shows that 95 percent are unregulated. The landfill sites still take in new garbage even when they are filled to capacity. As the waste decomposes, these sites release harmful greenhouse gases. However, using methane gas to generate energy instead could save the continent billions of dollars. We talk to sustainability scientist and author of the research, Nkweauseh Reginald Longfor.
What kind of economic and environmental damage results from uncontrolled garbage dumps?
About 70 percent of municipal solid waste ends up in landfills or unregulated dumpsites. In sub-Saharan Africa, for instance, 24 percent of waste is disposed of in landfills, while the rest is left on open dumps, streets, rivers, and other unsuitable locations.
We live in a society where waste is often disposed of without considering the cost to either the consumer or the producer. Waste decomposing in landfills releases greenhouse gases. The release of carbon dioxide, nitrates and hydrogen sulfides can harm people’s health, either by polluting the air we breathe or contaminating nearby water sources.
My research argues that this poorly disposed of waste also causes economic damage. To determine this economic damage, we compared the ongoing costs of poor waste management in 44 sub-Saharan African countries between now and 2060, with the costs of better waste management practices such as sanitary landfills and anaerobic digestion.
What are anaerobic digestion and sanitary landfills?
Anaerobic digestion is a natural process that uses an anaerobic digester (a sealed container) in which microorganisms such as bacteria convert organic waste into biogas. The most energy-rich component of biogas is methane, which makes up 50 to 75 percent of its content, depending on the type of waste and operating conditions.
Anaerobic digestion also converts organic waste into digestate, which is organic fertiliser useful for gardening or farming. Cities in Europe have used anaerobic digestion to convert organic matter found in municipal solid waste into electricity, cooking gas and heat for the past 20 years.
Sanitary landfills are municipal dumps where wells and pipes are installed to collect landfill gas, which is about 50 percent methane and 50 percent carbon dioxide, with a few other compounds.
This gas can be used to generate electricity, to fuel boilers, or processed for use in vehicles. Sanitary landfills are also designed to prevent pollutants from escaping into the air, soil, or groundwater. To be effective, they need to be properly located, built, maintained, and operated.
Municipal solid waste can be used to create energy.
How can this landfill gas offset economic damage?
If we capture methane, a harmful greenhouse gas, and convert it into energy, we reduce its release into the atmosphere, which lessens the effects of climate change. This in turn reduces the economic costs of problems like habitat loss, property damage, disease spread, and soil and water contamination.
Our research showed that the cost of installing sanitary landfill and anaerobic digestion technologies to convert waste into energy is only a fraction of the economic damage caused by methane emissions. These green technologies are cost-effective solutions for tackling the high economic costs of climate damage.
Secondly, the methane contained in organic waste can be a renewable energy source. This renewable energy source would help us decrease our reliance on fossil fuels. This would mean lower energy costs, more energy security, and less environmental and economic damage from fossil fuel use.
According to our research, by 2060, sub-Saharan African countries could generate between 20 and 58 million MWh of electricity just from waste. This could provide each African with an extra 100 to 230 kWh of electricity. From 2035 to 2060, the top 20 countries could produce between 0.2 and 3.3 million MWh to 0.4 and 8.5 million MWh of electricity from waste.
How did you calculate that current waste disposal practices will cause US$6.7 billion worth of damage in Africa by 2060?
Our study of 44 sub-Saharan African countries was quite revealing. All 44 countries use landfills to dispose of waste. What stood out was that over 95 percent of these landfill sites in Africa are unregulated. The sites still accept waste even after they are full, and continue releasing greenhouse gases as the organic waste decomposes.
We assessed the damage caused by these emissions one kilogram of methane emissions is estimated to cost, on average, US$1.943. Our research indicated that if we continued disposing of solid waste as we do now, the economic damage from methane emissions could reach billions of dollars. This cost seems to double every decade from 2025 to 2060.
While all sub-Saharan Africa countries are likely to experience some damage, certain countries could face costs running into billions of dollars. For example, by 2060, Ethiopia, Nigeria, the Democratic Republic of Congo, South Africa, and Tanzania could accumulate economic damages of US$6.7 billion, US$4.5 billion, US$4.7 billion, US$2.7 billion, and US$3.2 billion, respectively.
Which countries on the continent are most at risk?
My research has found that countries like Angola, Mauritius, and Cape Verde rely heavily on landfills for waste management. Their landfills are 70 percent, 90 percent, and 91 percent full respectively. These countries are most at risk. The estimated economic damage to Angola will rise from US$153 million in 2012 to a projected US$1.7 billion in 2060 because of their reliance on landfills.
Countries with growing populations and economies, such as Ethiopia, Nigeria, the Democratic Republic of Congo, South Africa, Tanzania, Madagascar, Mozambique, and Uganda, could face economic losses exceeding US$2 billion each by 2060 if they do not clean up their landfill practices.
All African countries must introduce waste reduction, reuse, recycling, and energy recovery, promoting public health, reducing greenhouse gases, and supporting a green, circular economy.
Sub-Saharan African countries should also adopt policies that promote private investment in the kind of clean waste management that leads to economic, social, and environmental benefits. —The Conversation
THE recent decision by the US states of Maine and Colorado to bar former President Donald Trump from their ballots marks an unprecedented moment in the evolving US political landscape.
The moves unveil the deepening divisions within the country’s political arena, where escalating political polarisation and legal battles are increasingly defining the narrative of national governance and public discourse.
POLITICAL RIFT
On December 19, the Supreme Court of the state of Colorado all seven of its justices appointed by Democratic governors —banned Trump from running in the state’s presidential primary in a divided 4-3 vote.
The ruling represents an unprecedented use of Section 3 of the 14th Amendment to disqualify a presidential candidate for the first time in history.
“This ruling, issued by the Colorado Supreme Court, attacks the very heart of this nation’s democracy,” said Alina Habba, Trump’s legal spokeswoman.
On December 28, US Maine Secretary of State Shenna Bellows also decided that Trump was disqualified from the state ballot in the upcoming presidential primary election due to his role in the US Capitol riot.
Bellows made history by prohibiting a presidential candidacy based on the same reason the rarely used insurrection clause of the 14th Amendment, which bars individuals who have participated in insurrection from holding office.
Trump on Tuesday filed an appeal of the decision by Maine’s top election official ruling him ineligible to appear on the state’s primary ballot. He also asked the US Supreme Court on Wednesday to invalidate the ruling by the Colorado Supreme Court.
HARASSMENTS
Days following Bellows’s decision, she fell prey to a “swatting call,” the state police said in a statement. Swatting is a false report of a crime or emergency that is intended to draw a police presence to a location.
“We were not home yesterday when threats escalated, and our home address was posted online. Swatting incidents have resulted in casualties although thankfully this one did not,” said Bellows in a statement she posted on Facebook.
“It’s designed to scare not only me but also others into silence, to send a message,” she said.
Colorado’s justices have also been the targets of threats, local media reported.
A gunman broke into the Colorado Supreme Court early Tuesday and took a security guard hostage while firing multiple gunshots before being arrested by local police.
Although the state police said the break-in was most likely not related to the controversial ruling, some local media outlets pointed out such a connection.
“The shooting is the latest example of violence and intimidation against Colorado’s high court and its justices after the court’s 4-3 decision last month,” Forbes said in a story covering the shooting.
“RIGGED ELECTION”
The banning of Trump from states’ 2024 primary ballots gives the appearance of “a rigged election,” said Sara Haines, the host of The View, a US daytime talk show.
The recent decisions in Colorado and Maine to remove the former president from their ballots will only push more people to believe that voting systems are unfair, said Haines.
“We have a nation that doesn’t believe in democracy, doesn’t believe in the voting,” she said.
“There is no doubt that Donald Trump is a threat to our liberties and even to our democracy,” said California Governor Gavin Newsom in a statement. “But, in California, we defeat candidates at the polls.”
“Everything else is a political distraction,” he said.
In a recent article published by The Hill, David Axelrod, a former Obama adviser, said that a judicial ruling to exclude Trump from the primary ballot would rip the country apart.
As the United States heads towards a critical election, Trump’s exclusion from two state ballots may set the stage for a highly contentious electoral journey.— Xinhua