[CSP] with storage for baseload energy. Why is that?
NANDU BHULA: Mainly because I think concentrated solar power does lend itself to operate in that kind of technologic space, especially with adequately sized storage. Now with Bokpoort we have 9.3 hours of thermal storage capability and we have shown in the first three months of production during the summer months we’ve managed to run 151 hours as a continuous operator. So the CSP with adequate storage can play in that technology space.
SIKI MGABADELI: And what is adequate storage capacity? How much would we need?
NANDU BHULA: Well, essentially, if you look at the normal daytime sunlight hours, you are looking at about eight, nine hours. And if you complement that with another eight to nine hours you are looking at a decent 17, 16 hours of operating potential. And for the South African grid with the morning peak and evening peak, we can easily cover that with the storage we have. And that storage that we do have is at full load, so we can also then strategise and reduce the load overnight so that we can become a load-following power plant.
SIKI MGABADELI: Does our current integrated resource plan allow for this? Does it give space for us to move forward in this direction?
NANDU BHULA: Well, I think the definition of CSP within the integrated resource plan would be in the field of peaking plants, and that is essentially to complement and support the grid over the evening peak. So the majority of the CSP plant will have come up first, ending with two to three hours of storage capability.
However, the possibility of using CSP plant as load-following or even baseload has not been fully explored, in my opinion, and therefore with Bokpoort’s 9.3 hours we are setting the discussion up for future consideration.
SIKI MGABADELI: And what sort of investment would this require because, as you know, when the topic of renewables comes up people talk about heavy initial capital outlay. What sort of investment does something like this require?
NANDU BHULA: The investment over the different bid rounds has been progressively coming down. We knew with renewables when we started off it was going to be introduced at a higher price, but the prices subsequently have really come down. We’ve seen PV, CV, and now CSP, following a similar trajectory with the latest bid rounds promising to show some very interesting prices that we are bidding in. So I think that would also create the space as far as that is concerned. The conversation regarding high cost is no longer a major handicap for us and we look at overnight capital cost for these plants are there.
However, I think the good news is that with the sun is not a commodity and the price of the sun and the energy that we are going to get stays the same for the lifespan…
SIKI MGABADELI: And talking about price, what would be the benefits for consumers in terms of tariffs?
NANDU BHULA: If you look at the CSP plants coming over the next few rounds…become close to parity with conventional profile power stations. So the impact would be such that there is a potential for the consumer to see some sort of change in the complete basket of tariffs. So we have the current technology space of open-cycle gas turbines with very high prices and these plants have the potential of displacing some of the costs that are being transferred into the tariffs.
SIKI MGABADELI: We know that Eskom is going to be starting to decommission some of their older power stations, the coal-fired ones. Could this kind of capacity replace that?
NANDU BHULA: Ja, I think the oldest in the fleet at Eskom, they have units of about 100 to 150MW, and the optimum size of our new CSP projects, which is our tower receiving power projects, are coming in at that MW range. So they do beg the question that we are now in the horizon of decommissioning the 1940/50’s technology plants and the question could be asked if we can produce bids at parity to coal tariffs then why not consider CSP to replace that?
It’s not to say CSP is the only option. The gas IPP projects and the coal IPP projects – but it’s just the concept to say PSP is at the level and CSP specifically, now we are talking about the power projects.
However, where they can start replacing these decommissioned units, we should consider them.
SIKI MGABADELI: Alright, thanks for your insights, Nandu Bhula, CEO of the Bokpoort CSP plant in the Northern Cape.
Nandu Bhula, CEO of Acwa Power Solafrica Bokpoort CSP Power Plant, answers the following questions in this video interview:
- Tell us about the Bokpoort CSP project in the Northern Cape.
- Thermal storage distinguishes this project from others, how does it work?
- How was the project able to deliver continuous power from commercial operation?
- In addition to peak periods, can CSP also be used for baseload power?
- Should there be a stronger case for more inclusion of CSP in SA’s energy mix?
- Are you planning on bidding for further projects?
Bhula was at the Moneyweb Renewable Energy Business Breakfast sponsored by Standard Bank in Rosebank on June 28 2016.