Assessing South African – American renewable energy projects

June 28th, 2016, Published in Articles: EE Publishers, Articles: Energize

 

Searching the outskirts for a solar baseload model

Pierre Potgieter, assistant editor at EE Publishers, is on a week-long tour of South Africa, sponsored by the US Embassy, seeking out various innovative renewable energy projects. The articles below form a diary of his travels.

Day 1: Monday 27 June

A solar park under construction in the heart of the Northern Cape sheds light on a combined solar photovoltaic (PV) and concentrated solar power (CSP) model which sets out to create renewable energy for baseload power.

Solar Reseve Jasper PV solar farm

 

Click here for Pierre’s report on day 2

Click here for Pierre’s report on day 3

Click here for Pierre’s report on day 4

Travelling the roads of the Northern Cape beyond Sishen, one will soon encounter pools of light which look like farm dams in the semi-desert landscapes. However, on closer inspection these turn out to be utility-scale solar farms.

One such installation, about 30 km from Postmasburg, is the 96 MW-DC Jasper solar farm. Developed by American company SolarReserve, Jasper consists of 325 360 modules of fixed polycrystalline solar photovoltaic (PV) panels on a 145 ha plot of land. The plant’s 96 MW-DC to 75 MW-AC ratio, higher than the usual 85 MW-DC to 75 MW-AC ratio, compensates for the natural degradation of solar PV modules to extend the plant’s lifespan by being able to produce 75 MW AC power to the grid for longer.

Jasper is located adjacent to another of the company’s solar PV plants, the 75 MW-DC Lesedi Power Project, and takes its name from the vermeil red rock which occurs in the area. Taking its name from the same rock, and a gem SolarReserve is currently focusing on, is the proposed (as yet financially unclosed) Redstone Solar Thermal Power Project, a 100 MW tower-type concentrated solar power (CSP) plant with up to 12 hours of heat energy storage by means of a molten salt system. This storage capability will enable the plant to generate electricity after sunset and provide power during the evening demand peak.

Baseload capacity and its scale have been two of renewable energy’s biggest drawbacks so far. Solar PV is limited to daylight hours, and its shortfalls highlighted at peak energy demand periods in the mornings and afternoons, limiting it to supplementary power generation rather than baseload power generation. Storage capacity could change all this, and if it could be scaled, which the company believes it can, the company says renewable energy could become a form of baseload generation.

Although CSP’s generation cost is decreasing and becoming more competitive with coal generation, it is still expensive. SolarReserve’s two solar PV projects (Lesedi and Jasper) are substantially cheaper than the proposed Redstone CSP plant. Jasper, the larger of the two PV projects, cost around R2-billion to build, compared to Redstone’s anticipated cost of R10-billion.

Combining the two technologies into one big project, however, could see solar PV generation offsetting CSP’s cost while retaining its potential baseload benefit.

The company intends to combine Redstone, as a baseload project, with its two adjunct solar PV plants on the same site to run them collectively as one large solar park. If this implementation proves successful, it could pave the way to more and larger such implementations, potentially opening the way for solar energy to become part of baseload power generation.

Click here for Pierre’s report on day 2

Click here for Pierre’s report on day 3

Click here for Pierre’s report on day 4

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