/ 5 April 2024

Water shortages impact hydropower as energy solution

The Gariep Dam in Free State has the maximum capacity 360MW of hydropower
Gariep Dam in the Free State. File photo

Frequent and worsening water shortages in South Africa have eliminated hydropower as an alternative solution to the energy crisis according to Titus Mathe, chief executive of the South African National Energy Development Institute.

In an interview with the Mail & Guardian, Mathe said before water shortages became a problem, hydropower could have been an important solution to the electricity shortages as a clean, renewable source of energy.

Mathe added that it would also be instrumental in providing baseload — the amount of electricity available at any given time for the country’s energy needs.

“At the moment, you can only get baseload from three energy sources — hydro, nuclear and coal — and that is it. We don’t have plenty of water and the timelines to build a hydro plant are too long, which means it will also take time for it to kick in”, Mathe said. 

Hydropower has been part of the country’s energy mix, but due to water shortages, it cannot be used as a main source of power, edging South Africa back to coal and looking at nuclear power as a source of baseload, Mathe said.

According to Statistics South Africa, hydropower contributes 3 484 megawatts to the energy grid. “Between 2013 and 2022, the capacity of hydropower energy grew by roughly 63.2 percent, increasing sharply in 2016 to 3 147MW from 2 148MW in the prior year,” the organisation said.

The biggest hydropower station in the country is Ingula, KwaZulu-Natal, with 1 332MW capability. It is operated by Eskom

The country faces significant water scarcity, with demand expected to surpass supply by 2030 by a projected gap of 17%, according to a World Bank report

The scarcity affects economic sectors such as agriculture, industry, energy generation and ecosystems, environmental degradation and biodiversity loss, the World Bank said.

The water crisis is also exacerbated by inadequate maintenance, no planning for population growth, mismanagement and corruption. As a result, many municipalities lose water to leaks, according to Water and Sanitation Minister Senzo Mchunu.

Climate change, which has caused erratic rainfall, also contributes to water scarcity and water shortages, Mchunu said last month.

To address the energy challenges and reduce emission levels, South Africa has been looking at alternative power sources that can replace coal as the main source of electricity.  

Renewable energy has been punted as an alternative to coal, but its intermittent nature has made it unsuitable. 

“With water, hydropower would fit in well with the Paris Agreement, but the alternative can be clean coal,” Mathe said. The Paris Agreement is an international commitment signed by member states of the UN to curb climate change.

Mathe said because baseload remained a challenge, South Africa should focus on investing in technologies that can clean the coal that the country has. 

“When possible, the coal we use can be retrofitted with clean technology to remove the sulphur particulates and mercury until we are ready to move to another baseload technology like nuclear power. But before that, we can’t let go of coal without another solution.”

He added: “The challenge is that these technologies are very expensive. Hydropower is also very expensive to build as is nuclear power, but in the long run, these technologies will benefit the country.”