Concentrated solar photovoltaic power (CPV) plant to deliver 22 MW in South Africa

South Africa’s largest concentrated photovoltaic (CPV) solar plant will be connected to the grid next month, supplying 22 megawatt-peak (MWp) of electricity to Eskom, enough to power approximately 5 000 homes.

The 44MWp CPV plant developed by French company Soitec in Touws River, Western Cape, will be the largest in the Western world, overtaking Colorado’s Alamosa solar generating facility, which opened in May last year and generates 37MWp.

The plant has approximately 50 percent of its 1 500 CPV panels already installed. When complete, it will generate enough power to run 10 000 homes.

“Testing has already been done in terms of output levels so we should have the grid connected within the next two weeks or before the end of December,” said Mark van Wyk, the portfolio manager of impact funds at Mergence Investment Managers. The Cape-based investment management firm is one of a number of investors and has put R65 million into the Soitec Touws River plant.

Soitec raised a $100m (R1 billion) bond for the project, which was the first publicly listed project bond ever issued for a CPV.

The project is one of the 28 preferred renewable energy installations by independent power producers announced by the Department of Energy in the first bidding window in December 2011.

These projects reached their financial close in November last year and most construction began at the beginning of this year.

It will be the third renewable energy project that Mergence has invested in to connect to the grid. The first was the Kalkbult 75MW solar PV plant developed by Scatec Solar in the Northern Cape, which fed its first power to the grid on November 12.

On Monday, the 20MW Herbert Power solar PV plant developed by a local company, AE-AMD Renewable Energy, was connected to the grid. The Herbert plant uses normal PV panels with sun trackers and only its first 10MW has been connected.

CPV differs from normal PV in that the percentage of the sun’s radiation it is able to convert to power exceeds 30 percent, according to the National Renewable Energy Laboratory. The efficiency of normal PV plants, on the other hand, is closer to 15 percent.

But normal PV has become the more favoured solar technology in most parts of the world rather than concentrated solar energies, as the pricing of the panels has fallen significantly over the past few years. According to Bloomberg data, some countries are now producing power from PV plants is 52 percent cheaper than concentrated PV plants.

The advantage of CPV plants was that “concentrated solar has the ability to store energy, but PV doesn’t yet”, Van Wyk said.

“This makes it comparable to a base-load power station. Yes, it is more expensive than PV, but the mix allows you to have the 5 percent electricity reserve margin because the power is there even if it’s overcast.”

CPV also uses half the solar panels or area needed to generate the same amount of power as normal PV. But on the downside, normal PV can generate power even on overcast days, while a concentrated solar plant needs direct sunlight. To date, 3 916MW of renewable energy has been procured by the department under the three windows of its Renewable Energy Independent Power Producer Procurement Programme.