It makes economic and technical sense for electricity utilities such as Eskom to source as much new wind and solar photovoltaic (PV) energy as possible, says EE Publishers MD Chris Yelland.
Speaking at a seminar hosted by EE Publishers and Nedbank, on Tuesday, he said the only limitations were the ability of the renewable energy sector to deliver the planned new capacity requirements, and the ability of the electricity grid to handle this new variable capacity.
“In the new world of power generation, the old paradigm and approach of dispatching baseload, mid-merit and peaking generation capacity, in that order, to meet electricity demand is being turned on its head.
“With the massive reduction in the price of renewable energy from wind and solar PV plants over the last five years – less than a third of that of energy from new coal and nuclear baseload plants – a new approach to power generation beyond baseloadism is emerging,” Yelland said.
He added that international experience showed that, in the years to 2030 and beyond, there was no economic, technical or other reason for the majority of South Africa’s new generation capacity requirements not to be met by wind and solar PV capacity, backed up by flexible generation capacity.
The Nedbank/EE Publishers seminar discussed the enablers for flexible power generation, which include gas-to-power, battery energy storage, pumped water storage, thermal energy storage and other energy storage systems to complement intermittent wind and solar renewable energy sources, and to provide auxiliary grid services.
National Energy Regulator of South Africa CEO Chris Forlee stated that the country had to consider flexible generation, given the energy supply challenges it is facing.
“For me it is not an either/or situation regarding alternative generation and baseloadism, but it should rather be a complementary combination.”
International Finance Corporation principal investment officer Stephan Vermaak commented that, although renewable energy had become cheaper than fossil fuels, their penetration depended largely on the flexibility of the grid to manage intermittency.
Vermaak added that new technologies such as battery storage to effect grid flexibility were still too expensive for financially weak utilities.
Meanwhile, power source manufacturer Wärtsilä Africa and Europe project development director Stefan Nygard said renewable energy was the cheapest source of electricity in two-thirds of the world.
He believed that lithium-ion batteries and flexible gas will become the biggest enablers of flexible generation.
“As long as decision-making [of governments] is based on economic and climate impacts, renewables will always win. Once renewables use reaches 80% globally as baseload, there is no more a role for inflexible generation,” said Nygard.