Burned out on its aging coal-fueled
power plants, South Africa is rethinking its
energy portfolio. The country is planning
up to eight new nuclear power plants
by 2029 to stabilize its power grid. The
program, which could cost up to US$100
billion, would generate 9,600 megawatts
South Africa currently relies heavily on coal and has only one nuclear
plant. But frequent electricity blackouts
caused by power supply shortages have
disrupted life for residents and business
alike, leading to calls for changes. The
country’s finance ministry says the lack of
reliable power is the top constraint on the
economy, The Wall Street Journal reported
earlier this year. South Africa hopes to
have the first new plant running by 2023.
But some see funding problems on the
horizon—along with continued power
supply instability. An editorial in South
Africa’s The Times newspaper complained,
“The government is unable—or unwill-
ing—to specify exactly how it will be
funded…. Neither is there a coherent
explanation of how this country will make
do with its stuttering electricity supply for
the next decade or so until the first of the
nuclear power stations comes on stream.”
Others fear that the awarding of large
contracts could breed corruption.
“[T]he potential for corruption is there
for all to see. The administration must
ensure a competitive [bid] process,” Anne
Frühauf, a southern Africa analyst at Teneo
Intelligence, told Bloomberg in December.
The Roadbot automates the typically labor-intensive process of identifying
and sealing cracks in road surfaces, and requires just one operator.
solids left at the end of the water treatment process. The high-grade biosolid generated by
the facility can be sold and reused in farms and city gardens. Before the project team could
get full funding, though, it had to sell a key stakeholder group—the organization’s board of
directors—on the economic value of turning sewage into electricity.
The project team learned firsthand from European wastewater-treatment facilities that use
the same thermal hydrolysis technology. After biosolids are treated at high heat and pressure
to kill any pathogens, organic matter becomes food for microbes, which in turn convert it
into methane. To prove the system would work in Washington, the team built a small pilot
plant, says Chris Peot, director of resource recovery, D.C. Water, Washington, D.C., USA.
The pilot proved that thermal hydrolysis would produce more gas for the electricity-generat-ing turbines than a conventional biosolids digester.
“Not only are we producing clean, green renewable power so we don’t have to buy as
much power off the grid, but we’ve drastically reduced our carbon footprint, which is good
because we’re the biggest user of electricity in Washington, D.C.,” Mr. Peot says. “The pilot
testing showed all of that. It made the economic argument for us.”
For the developers of Roadbot, a US$1.4 million proof-of-concept project, dem-
onstrating small-scale success is a must. The Roadbot automates the typically labor-
intensive process of identifying and sealing cracks in road surfaces, and requires just one
operator. The project team at the Georgia Tech Research Institute in Atlanta, Georgia,
USA developed an algorithm and lighting system to identify the cracks at 5 miles
( 8 kilometers) per hour, or 88 inches (224 centimeters) per second—which means the
machine has just 136 milliseconds to identify and locate each crack. A high-pressure
hydraulic system then precisely dispenses asphalt into the fissures.
Rather than constructing the entire robot at once, the team engaged in iterative test-
South Africa’s only nuclear
power station, in Koeberg