South African power utility Eskom said on Monday that it had a budget specifically allocated for a concentrated solar power (CSP) demonstration and pilot project of R7,5-billion over the next ten years, as the utility sought to diversify its energy mix away from coal.

Eskom technology, strategy and planning manager Barry MacColl, however, emphasised that this was a budget request that still needed approval through the tariff increase application, which the utility submitted to the National Energy Regulator of South Africa last week.

Eskom was awaiting the outcome of its second multi-year price determination, which would finalise related budget figures.

"CSP funding is in the research budget that was sent to the regulator," he further explained.

MacColl stated that Eskom had a R30-billion budget for pilot and demonstration projects over the next ten years. Smart grids were allocated a budget of some R90-million over the next ten years.

Estimates for the CSP plant indicated it would cost in the region of R6-billion, which MacColl pointed out would be within the budget, if approved.

"As we build these things, we must take life cycle costs into account. We must not have short-term horizons of three of four years. If we keep focusing on short term these things will get delayed," he added.

The CSP plant, which Eskom had deferred in light of the global financial crisis, would be located in the Northern Cape.

"We are going to build it," affirmed MacColl.

"I wanted to assure you that we have files and files of technical drawings of this plant, and we know what this plant is going to look like. We have the designs for this plant, and hundreds of diagrams," he further emphasised.

The plant would be a 100-MW electrical plant, with 500 MW thermal capacity, and storage capabilities of 14 hours. He also explained that the plant would have a 68% load factor.

"The sums point towards using molten salt technology, largely because of the storage capacity," noted MacColl, who added that the plant would likely have a circular shape with a centralised tower, and the power output would be constant.

The central tower would be 190-m tall and 24 m in diameter, and would be made of concrete. The receiver is a critical plant component and is made of a high nickel alloy.

"The heliostats are getting a lot of our attention at the moment, and we believe there is a lot of potential for local content," added MacColl.