Room for renewables and nuclear in energy mix - researcher

Johannesburg – Renewable energy falls short of being a base load power source in South Africa, suggests a researcher.

Ben Heard, director of Bright New World organisation and PhD Candidate at the University of Adelaide, has conducted research to dispute the claims by the Council of Scientific and Industrial Research (CSIR) that renewables have the capacity for a 70% share of South Africa’s energy sector.

The research, conducted by CSIR analysts Jarrad Wright, Dr Tobias Bischof-Niemz, Joanne Calitz and Crescent Mushwana, showed that renewables would be the least cost option for South Africa.

READ: Proof that solar, wind, gas - not nuclear - is best for SA

It showed that the renewables' 70% share of the energy sector by 2040 would be R87bn cheaper than a scenario where nuclear is the base load, followed by coal and some renewables. This scenario would also reduce South Africa’s carbon emissions by 60%.

The CSIR is not the only organisation which has conducted a study on the feasibility of a future with renewables. McKinsey and Company released a report last year which shows that by 2050, 77% of Africa’s energy capacity will be driven by renewables.

READ: Over 70% of Africa's energy to come from renewables

However, Heard told Fin24 in a telephonic interview that the suggestion that renewables could be the bulk source of energy supply is “preposterous”.

Heard conducted research to measure the feasibility and reliability of renewable energy against four criteria. These are the ability of renewables to meet energy demand forecasts, reliability over different time-scales and resilience to extreme climate events, transmission and distribution requirements and ability to provide ancillary services. Heard’s research paper suggests that renewables do not fulfil these requirements. 

However, he agreed that there is room for renewables in South Africa’s future energy mix. He proposes an energy mix with nuclear as the base load, followed by renewables such as solar and wind to meet variable demand and gas as a back-up for renewables.

“There is no threat to solar photovoltaic (PV) and wind development from other energy sources. They have a large role to play,” said Heard. However, there needs to be another energy source to ensure the reliability of energy supply and nuclear can fit that role, he explained.

“The thing about renewable energy sources, each country must find its advantages in renewables and use them appropriately.” In South Africa’s case this is “good sunshine” and wind. “We should pair that with a nuclear power sector to come up with a supply which is reliable, affordable and clean,” he said.

Cost

Assuming the electricity system is reliable, the cheapest source of electricity in South Africa is solar PV, and the second-cheapest is wind, said Heard. “But solar PV and wind turbines do not provide the stability and reliability that can drive the entire economy.” Rather, they are effective additions on top of a stable system.

Nuclear power may be more expensive, but it is more reliable than renewables. Heard added that the cost differences between coal and nuclear are minimal. However, capturing carbon emissions from coal would make it more expensive than nuclear, he added. They’re both cheaper than diesel.

“When investing in the coal sector or the gas sector, you are very exposed to the price of fuel,” he said. Nuclear has the advantage in that fuel costs are low and likely to stay consistent throughout the life of the plant.

READ: Delays in nuclear projects drive costs - expert

In response to a question about how the cost of building a nuclear plant is driven by time delays, Heard said it is possible to get good capital costs for nuclear projects, provided that a country runs globally competitive tender process. “Provided you run a proper, transparent process you can get excellent cost on nuclear.”

The nuclear energy sector should be treated as a normal competitive industry, like any other, he said. “If you do that you can get excellent time and cost outcomes.”

Heard said that problems come in when the nuclear sector becomes over-regulated, which is where efficiency problems creep in and then there are delays.

“The challenge is to ensure the tender process is open, competitive and transparent and the risk is managed appropriately. If that happens, South Africa can be a winner.”

Heard added that South Africa is ahead of most nations considering nuclear for the first time. “South Africa has the institutional infrastructure required… South Africa has what it takes to have a nuclear sector expand successfully.”