Charl du Plessis, Head of Sales at Energy Partners Solar – a division of Energy Partners and part of the PSG Group of companies – says that the security of electrical supply will increasingly place pressure on businesses across South Africa’s market sectors.
Looking to mitigate the impact of the tariff increases over the coming years, du Plessis says, “First, we would recommend installing a grid-tied solar photovoltaic (PV) system. The payback period for a PV system, which can be installed within three to six months, could be as short as three years, if the Section 12B accelerated tax write-off for renewable energy assets is also used. Some service providers offer renewable energy on the basis of a Power Purchase Agreement (PPA), at up to a 50 percent discount to grid rates,” Du Plessis says.
He adds, however, that a PV system still requires a stable power grid to feed into, so for intermittent power cuts – like load shedding, a generator that can provide the essential load is also needed.
The best solution, he says, is a hybridised system that uses both a PV system and a diesel generator. “For this step, it is important to engage an expert service provider to combine the two supply sources in an energy centre that automatically regulates the power supply to the business. That is the only way to guarantee that the system is safely installed and can perform at maximum efficiency.
“In an energy centre configuration, the PV system can supply the bulk of the power required by a business during load shedding in peak daylight hours, while the generator either idles on standby or runs at reduced capacity to provide additional power. When the PV system is unable to operate, such as on cloudy days, the generator takes over bulk power supply. This hybrid system can reduce fuel consumption significantly and typically saves around 70 percent of the cost of diesel generation.”
Du Plessis says the other option available combines battery storage with a PV system. The capital outlay for this is substantially more than for a diesel generator. For a battery system that provides around 100 kW of power during load shedding, the cost is currently around R1.5 million. However, it does offer several advantages.
“A battery system can be used to reduce power costs when the grid is on. Alternatively, it can be set to feed power into the company’s smart grid during operating hours (a method known as peak-shaving), or to charge the battery during off-peak hours when energy tariffs are lowest, then discharging the system during peak hours (known as time-of use arbitrage). “
Du Plessis anticipates that the cost of batteries will reduce substantially over the next ten years, which will make this option more viable.
While South African businesses are increasingly aware of the importance of a secure power supply, Du Plessis emphasises that it is essential for every company to start looking for capable service providers to ensure they have affordable, uninterrupted power in the coming years.
Enquiries: Charl du Plessis, Energy Partners Solar. Tel. + 27 (0)11 974 3899, or visit: www.energypartners.co.za