Retire power stations rather than trying for ‘clean’ coal

Eskom this week reiterated that without additional capacity, it would continue to see an electricity shortfall of 4 000 to 6 000 megawatts over the next five years. But it also said it would retrofit old coal-fired power stations with technologies that will partially improve air pollution and the respiratory health crisis.

The technologies used to reduce air pollution and tackle carbon emissions are different. But Jesse Burton, an associate at the Energy Systems Research Group (ESRG), says addressing air pollution and dealing with climate change through greenhouse gas emission reductions need not be a trade-off if some coal-fired power stations are retired early.

Burton presented findings for different scenarios at Eskom’s various coal-fired power stations. It will cost Eskom R300-billion to retro-fit its current coal fleet to meet the minimum emissions standards relating to particular matter, the utility told parliament’s portfolio committee on minerals and energy. The utility has historically sought exemptions for power stations that emit far above the minimum emissions standards.

For the Duvha and Matla power stations in Mpumalanga, the ESRG found potential cost and greenhouse gas emissions savings if compliance with the new standards is suspended for these stations, and they are instead retired early.

“We propose that the department of environmental affairs considers suspending compliance requirements for the best-performing (in terms of pollutants) stations, and in exchange, Eskom agrees to retire the stations by 2030 at the latest.

“For the remainder of the fleet, Eskom should commence retro-fitting the stations subject to ongoing cost assessments. Phasing out coal in the power sector by 2040 is costoptimal for South Africa to fulfil its commitment to the Paris Agreement goal of limiting warming to well below 2°C without significant impact on the economy, ” Burton said.

The global demand for coal dropped to pre-world War II levels in 2020, according to the International Energy Agency. “A forecasted rebound in 2021 could be short-lived, with no further increases in demand expected between 2021 to 2025, provided the economic recovery from the pandemic continues and policies remain unchanged,” it said.

The global coal sector is advocating and planning for what is now referred to as clean coal technology.

Clean coal is regularly poised as a climate change-accelerating greenhouse gas emissions solution while the different technologies are conflated as one. In fact, the most common technology will address air pollution — driven by particulate matter, sulphur dioxide, which contributes to acid rain and respiratory illnesses and nitrogen oxides, which contribute to smog and respiratory diseases — but not necessarily climate changeaccelerating carbon emissions from the same power stations. Carbon dioxide is the primary greenhouse gas responsible for global warming.

Carbon-capturing technology, where carbon dioxide is trapped and stored instead of being released into the air, will come at exorbitant costs.

Proponents of clean coal believe that because coal remains part of SA’S integrated energy resource plan beyond 2030, efforts to address its dirty air legacy must be prioritised.

But researchers maintain that coal can never be completely clean.

“Clean coal is often touted as a solution to air pollution, as coalfired power has become increasingly uncompetitive against renewable energy. In some countries with significant domestic resources, policymakers may perceive clean coal as a way to utilise a national resource while also responding to global norms on pollution and climate change. However, the term is used loosely and often refers to divergent technology options,” said Burton.

In 2019 the Centre for Environmental Rights said the technical upgrades to expiring coal-fired power stations will still be inadequate to address minimum air quality emissions standards compliance relating to toxic air pollution. No solutions can completely mitigate coal’s enormous resource consumption and harm to health and the environment, the report found.

Burton suggests that the options for Eskom boil down to whether electricity will be cleaner, more affordable and more accessible.

“The key question then is whether, for the same or better emission outcomes, alternatives can meet electricity system demand more cheaply or practically. Can newer coal plant technologies, or stations retro-fitted with carbon capture and storage, compete with alternatives such as renewables and flexible capacity (pumped storage, batteries, or gas) on cost and emission reductions?”

The cost-savings models favour retro-fitting power stations to address their contribution to toxic air, but at what cost to climate change mitigation?

In many cases, retiring old power stations while rapidly rolling out new renewable energy to the grid will be complemented by a reduction in the cost of electricity given the steady decline in renewable energy prices. This suggests improving air quality and mitigating climate change does not need to be an either/or.