‘The energy crisis seems hopeless and our national leadership even more so. But SA’s energy problems are fixable, and in a shorter time than many believe. In fact, with the correct interventions the country could soon be exporting excess electricity to its neighbours,’ says Tetra Tech director Paul Tuson, an electrical engineer with more than 30 years’ experience in the power industry in SA.

According to the SA Housing Market Report, there were about 17m households in SA in 2020.

Tuson says if a 5kW rooftop solar photovoltaic (PV) system were to be installed on just one 20th of these structures, it would amount to 4.2GW.

That is the generation capacity of a large Eskom coal-fired ‘six-pack’ power station, and more than twice the capacity of Koeberg.

While he admits this would not provide around-the-clock energy, it would be an important addition to supply and could be significantly improved by adding batteries, to be charged when the sun shines, and discharged at night.

‘Add to the above 4.2GW capacity from office blocks, commercial buildings, schools, factories, hospitals, warehouses and millions of carports and car parking areas, and the potential capacity from solar PV is significantly larger.’

In his opinion piece in Business Day, Tuson says legislation is urgently required to allow consumers to become ‘prosumers’ – consumers who can also export their power to the grid and be compensated for it, albeit at differential tariffs.

‘Time-of-use tariffs could be implemented to encourage better electricity use behaviour. Tax incentives and financial models from large financial institutions should be accelerated to assist customers who would find the capital outlay for solar PV and battery storage systems prohibitive. Rooftop PV and batteries can be installed within weeks.’

Tuson’s suggested interventions include:

* Install PV and battery energy storage systems at every structurally sound industrial, commercial, educational, medical and residential structure;

* Install utility-scale solar PV generation together with batteries around the country, even in areas with less attractive solar irradiation levels – but only where transmission and distribution capacity is available;

* Construct strategic transmission lines in the Northern Cape and adequately compensate landowners for transmission line servitudes and power lines on their properties. This would unlock an immediate 5GW-10GW of shovel-ready utility-scale independent power producer (IPP) solar PV projects; and

* Contract floating storage regasification units and construct 1GW open cycle gas turbines in conjunction with these units at coastal cities such as Richards Bay, East London and Gqeberha.

Tuson says as the penetration of inverter-based variable renewable generation increases, the need for mitigating flexible power plants also increases to counteract the intermittency and variability of the renewable energy.

‘System flexibility can be obtained from batteries, but another important source of flexibility comes from open-cycle gas turbines and diesel engines. Flexible thermal power plants also provide fault level and system inertia, and they can be called on during extended bad weather periods or as backup generation when other conventional synchronous generation has unplanned and planned outages.’

While Tuson admits these interventions will not provide an immediate remedy to SA’s power woes, he argues they can provide an environmentally friendly, best-cost, reliable and technically achievable direction for the energy sector in the short, medium and long term.

Full opinion piece in Business Day