JUST HOT AIR?

In a world increasingly affected by global warming, the turn to renewable energy sources is a no-brainer. But it’s important to note how they stack up on the feasibility scale

We know renewables are the energy sources of the future. But how viable are they right now? A study led by Mark Jacobson, professor of civil and environmental engineering at Stanford University, has found that switching the world entirely to renewables would cost as much as $62-trillion — but it would take just six years to pay back that investment.

Grid operators already have the tools to power economies with wind, hydro and solar, with support from batteries, flywheels and other technologies, Jacobson says.

Elon Musk’s Tesla agrees. In early March, the company published a world energy road map that says 30,000GW of wind and solar farms, plus 240 terawatt hours of storage, would be enough to power the world — while also trimming power costs, land requirements and mineral extraction.

Not everyone is of the same opinion, of course. South Africa’s de facto chief energy planner, mineral resources & energy minister Gwede Mantashe, for example, recommends that the country should invest in additional coal and nuclear plants, and view renewables as a supplementary power option.

Despite the cost benefits of solar and wind, and the speed at which facilities for these power sources can be built, Mantashe cites their variability as a major drawback, saying traditional energy technologies deliver power more consistently.

In 2021, the Koeberg nuclear power plant ran at a capacity factor of 74.6%, says the Council for Scientific & Industrial Research (CSIR). This measure — which has no bearing on unit costs — compares electrical output from a facility over a given year with its theoretical maximum output (a scenario in which the plant runs at full capacity for the full year).

South Africa’s coal fleet had a capacity factor of 54.2% in 2021, against 37.8% for concentrated solar power (using mirrors and lenses to concentrate sunlight), 35.8% for wind and 26.4% for solar power.

This discrepancy between traditional technologies and renewables is what Mantashe refers to when punting the need for “baseload” energy — the minimum energy required in a grid at any given time.

But “baseload” energy is also synonymous with plants that deliver power most of the time, and that don’t change their output quickly. So, in addition to coal and nuclear, hydropower can also be considered a baseload technology

(though, as a water-scarce country, South Africa’s ability to scale up its hydro capacity is relatively limited).

There is, however, an increasing belief that the era of baseload energy is drawing to a close. It will be replaced, the argument goes, by a far more flexible and competitive system, in which electricity generators compete in the spot market to supply power every single day.

Advance Australia fair

In its road map, Tesla cites the state of South Australia, which installed batteries in 2017, as a pioneer in the shift away from baseload sources towards renewables and batteries.

In the three months to end-February, wind and solar made up 80% of the state’s electricity mix, data from the energy market operator shows.

South Australia — home to the city of Adelaide, as well as mining and manufacturing operations — shut its last coal-fired power plant in 2016 and is working to muscle gas out of the equation as well. It’s doing this using advanced big batteries and other technologies that deliver critical grid services such as inertia and frequency control.

The rising penetration of solar and wind is keeping costs well below those of other, coal-reliant, states. In January, the wholesale cost of electricity was A$57.20/ MWh in South Australia, against A$98.96 in Queensland and A$94.39 in New South Wales.

The rest of Australia is now following South Australia’s lead. It’s aiming for an average of 82% renewables in 2030, though it could

reach the 100% mark at times from as early as 2025.

Portugal and Denmark have already beaten it to that milestone. The UK, for its part, has run on 51% renewables for the past 12 months.

“Many large countries now have about half of their electricity generated from renewables, and their grids are not collapsing,” Hartmut Winkler, physics professor at the University of Johannesburg, tells the FM.

“Technologies are constantly evolving to allow even these countries to up their renewables fraction further.

“South Africa will learn from experiences around the globe and adjust accordingly when renewables start producing a more significant fraction of this country’s electricity.”

For the time being, coal still generates more than 80% of South Africa’s power, with nuclear at about 5%. But following a gradual transition, the optimal mix in 2050 would probably consist of 70% renewables, Winkler says.

However, he adds, both politics and narrow interests seem to be holding the process back.

“Right now, one gets the sense that there are people with a lot of influence who have a stake in the coal and/or nuclear sectors, or who are currently earning a lot of money servicing the Mpumalanga coal plants,” he says.

He believes there has been a concerted campaign by this group to depict renewables as elitist and a “Western plot”. As a result, the energy sector has become an ideological battleground, “hamper[ing] a cohesive, nonpartisan response to the electricity crisis”.

The ‘Wild West’

Nevertheless, new rules allowing companies and municipalities to reduce their reliance on Eskom have unleashed a boom in renewable energy investments. According to Eskom, projects with a staggering 20.2GW in combined capacity are seeking connection to the national grid.

While this could eradicate load-shedding altogether, Winkler warns that there’s a risk of a “Wild West scenario”, in which the surge in clean power generation is almost unregulated.

A functional national grid is critical and keeping it that way will require sound regulation and good long-term planning on the part of the state.

For Stefano Marani, CEO of JSE-listed gas and helium company Renergen, that should include a role for domestically sourced gas as old coal plants are retired. He argues that gas is significantly less polluting than coal and will be needed to meet peak power needs and sudden demand spikes.

Energy system modellers such as the University of Cape Town’s Energy Systems research group, the National Business Initiative (NBI) and the CSIR, agree that a modest amount of gas will be needed during the energy transition.

That said, the NBI says it would be too risky to set up local gas-to-power infrastructure this late in the fossil-fuel game, as South Africa would end up with costly stranded assets if gas power becomes obsolete.

And, because gas plants will probably run at very low capacity, the organisation favours liquefied natural gas (LNG) imports, rather than local supply.

Marani disagrees, saying South

Africa’s ports are not deep enough to handle LNG-carrying ships. These vessels would have to moor at sea and gasify their liquid cargo before moving it onshore a process that would then have to be reversed for inland transportation. It makes sense, in his view, to develop a domestic gas market.

Some question the wisdom of investing in gas in the first place, given the risks involved. The Canada-based International Institute for Sustainable Development said in a report last year that South Africa wouldn’t need gas power until 2035, if at all. It argued that the country should wait until 2030 to assess its need for gas.

The big jobs question

Meanwhile, to remove additional roadblocks in the energy transition, South Africa will need to invest in skills, as there’s already a shortage of qualified rooftop solar installers.

This will form a key part of the country’s renewable energy master plan, says Gaylor Montmasson-Clair, who is facilitating the planning process. The industry will look to bring experienced installers who don’t have the requisite qualifications “back into the system”, and consider training and mentorship programmes, he adds.

The rooftop solar boom will help alleviate job losses as Eskom coal-fired plants reach their end of life. So, too, will large-scale wind and solar projects particularly if South Africa develops a local component manufacturing industry.

A study commissioned by the South African Photovoltaic Industry Association found that the domestic solar value chain already employs about 20,000 people, and there is still significant opportunity to scale up local component production.

The Global Wind Energy Council says wind power installations to 2026, coupled with ongoing operations and maintenance beyond, could create

37,000 full-time equivalent jobs.

Montmasson-Clair says South Africa could offset job losses in the coal value chain by growing biomass crops around disused mines and processing them in aviation fuel refineries.

A study by conservation NGO WWF South Africa, supported by research organisation Trade & Industrial Policy Strategies, found that all the country’s 4,000 coal truck drivers could switch to transporting biomass.

Selby Sithole, an engineer who runs a business servicing the coal sector, hopes to see such alternative employment opportunities materialise soon. As things stand, the closure of coal mines around his hometown, Delmas, is already fanning anxiety about the energy transition.

For now, there are only a handful of job-creating renewable energy projects in the heart of the coal belt, and the local agricultural sector cannot absorb all exmineworkers nor can farms pay them nearly as much as they used to earn.

“And the municipality is now suffering because people can’t pay their bills,” Sithole says. “So I think government really needs to speed up renewable projects, especially in Mpumalanga.”

All this, taken together, means South Africa’s adoption of renewables is increasingly becoming a reality.

This article is part of a series by news site explain.co.za on the just energy transition. Reporting in this series was made possible by funding from the African Climate Foundation