JSE-listed Altron subsidiary Powertech System Integrators (PTSI) launched its fully funded solar rooftop photovoltaic (PV) solution for South African corporates last month to take advantage of the country’s rapidly expanding renewable-energy sector.
PTSI strategic project executive Kobus Morgan explains to Engineering News that the hybrid energy solution uses grid power and solar energy, which are viable for South African energy users in the view of the high electricity tariffs. The higher tariffs subsequently increase operating costs and impact on the bottom line.
PTSI’s pilot project for the solution was unveiled at its head office in Menlyn, Pretoria, last month.
The pilot rooftop solar PV solution generates 60 kW of direct current (dc) power, of which 50 kW is converted into alternating current (ac) power.
This grid-tied system is placed on a rooftop or shaded car park and is based on two major components – PV modules that can convert sunlight into current and an inverter (or multiples thereof) that can convert dc power generated by the PV modules into usable ac power.
The solution is aimed at companies that have large roof space and constant baseloads every day, such as mining companies, commercial property owners and industrial facilities.
The solution will be built and owned by PTSI, and the electricity generated by the system will be provided through a power purchase agreement (PPA).
The rooftop PV programme comprises many projects, which PTSI hopes to implement over the next five years. The company aims to install 150 MWp of PV plants in South Africa over this period.
Some of the projects will be executed on an engineering, procurement and construction basis and others in accordance with a PPA, which implies that an entity other than the customer makes the initial investment.
PTSI has partnered with a financial institution that is willing to share the risk of this initial investment.
“Each solution and financing solution will be tailored specifically for every customer, but a PPA is usually set for a specific period that enables the seller to recover its investment in the power plant – typically operated over 10, 15 or 20 years. With the PPA offered by PTSI, our clients have the option to buy the power plant at a reduced price after five, eight and ten years, based on a depreciated net present value and reduced yield formula,” says Morgan.
He adds that the price of the electricity produced by the PV system will be equal to the tariff currently in place, excluding a nominal discount.
Customers will subsequently benefit from the long-term saving and reduced electricity costs.
PTSI will operate and maintain the system and customers are offered buy-back options during the contract period.
Further, rooftop PV can also form part of a smart grid or a microgrid, where electricity use automatically switches between power sources when required, ensuring a consistent supply of energy during outages and load-shedding.
This option also involves the deployment of single or multiple energy-storage systems.