/ 27 May 2016

Storm over pebble bed modular reactor as Eskom ponders its resurrection

Nuclear dawn?: Eskom argues that one of the advantages of pebble bed modular nuclear reactors is that they can be sited where they are needed and do not require thousands of kilometres of electricity transmission lines and pylons.
The utility had originally implemented stage 2 load-shedding on Monday, which requires that 2 000 megawatts be rotationally shed from the system.

Eskom is seriously considering resurrecting the pebble bed modular reactor (PBMR), the power utility said this week.

Its proponents believe this is an opportunity to resuscitate a poorly understood project that should never have been shut down, though sceptics think it would amount to little more than a naive attempt to bring an expensive pipe dream back from the dead.

The revival of the nuclear project was still at an early stage, Eskom’s spokesperson, Khulu Phasiwe, said. “It is important to note that Eskom still has intellectual property rights on the project and that we are seriously considering reinstating it.”

The intention to revive the PBMR, mothballed by the state in 2010, was revealed by Eskom’s chief executive, Brian Molefe, earlier this month. He was quoted in media reports as saying that research on the pebble bed would be reopened under Eskom’s chief nuclear officer.

The project has a fraught history. The PBMR is South Africa’s version of a type of nuclear technology design for high-temperature gas-cooled reactors, first developed in Germany, which used helium gas as a coolant and graphite as a moderator. These types of reactors are deemed to be generation IV designs, with generation III technologies currently being built in many countries.

A 2011 paper by Stephen Thomas, emeritus professor of energy policy at the University of Greenwich, said South Africa’s major innovation on earlier PBMR designs was that the helium coolant would be fed directly to a gas turbine instead of passing through a steam generator. The PBMR was also designed to be modular and the ability to “add units incrementally was expected to make the design more suitable for small national electricity systems”.

But, after more than a decade of research and about R10-billion in state funds, the project was shut down by then-minister of public enterprises Babara Hogan. The reasons cited included that it had been unable to secure an anchor customer or investor and had consistently missed deadlines, with the construction of a demonstration plant routinely delayed. At the time, about R30-billion more was needed and, in the wake of the global financial crisis, the government was forced to “reprioritise its spending obligations”.

Plans to participate in the United States’s next-generation nuclear plant programme as part of a Westinghouse consortium fell apart when Westinghouse withdrew.  Despite the controversy, the proponents of the PBMR argue it was ahead of its time and its successes were poorly communicated to the wider public.

“To my mind it should never have been shut down,” said Kelvin Kemm, chief executive of Nuclear Africa and chairperson of the Nuclear Energy Corporation of South Africa (Necsa). The project team at the time made the mistake of focusing on the technology development and did not focus on public awareness, including educating the political leadership of advances made on the PMBR project he said. Another mistake was the emphasis placed on getting a “perfect system on paper” instead of building a demonstration reactor to prove it could be built, he added.

The reactors are modular, designed for dispersal over a large area and did not need water for cooling, Kemm said. A PBMR reactor could be placed wherever it was needed and did not require thousands of kilometres of transmission lines.

Funding would not necessarily be a problem, he said, arguing that over a decade South Africa spent about R10-billion on the PBMR, but in just three years the country spent more than R12-billion the 2010 World Cup stadiums.

The advances made on fuel production for the PBMR were not appreciated, he said. The fuel plant was still 100% intact at Necsa and had produced fuel to world standards.

But other experts are sceptical about the chances of reviving the project. Thomas said he was “surprised Eskom should go back to this technology”, given that, in 2002, the Eskom board expressed concerns about the project and it stopped funding it soon thereafter. In 2008, it was Eskom “that killed the project” when it said it would not order reactors.

The technology is based on a small 15 megawatt German prototype, the AVR, which was closed down in 1989. The site was badly contaminated, Thomas said, and was expected to cost €5-billion to decommission. Another 300MW demonstration plant was completed in 1985, but it closed in 1989 after a dismal operating history. No other PBMR design had been built, he said.

The claims that a PBMR reactor cannot melt down did not mean there were not other safety issues, he said. “Until the design is complete and subject to a comprehensive review by an experienced safety regulatory authority, we won’t know.”

China, which took out a licence for the design in 1989, has said it expects to launch its version of the technology by November 2017. Thomas cautioned that forecast completion dates for nuclear projects “are notoriously over-optimistic”.

The rebirth of the project raises other questions, not least of which is financing it in the face of Eskom’s financial difficulties and the government’s plans to procure 9 600MW of conventional nuclear power. 

Enoch Godongwana, former deputy to Hogan and chairperson of the ANC’s economic transformation committee, said indications at the time it was shut down were that the PBMR was viable, but the difficulty lay in commercialising an unproven technology. 

This required large financial resources. If this proposal were to go ahead, clarity was needed on, among other things, intellectual property rights, he said. A key problem for reviving the PBMR was that non-nuclear technologies, especially renewables, are rapidly improving in performance and cost, said Thomas.

Grové Steyn of Meridian Economics said any hope of reviving the PBMR was “naive”. Even when South Africa was running a fully fledged PBMR programme, “for those who understood the magnitude of developing a new technology of this nature, it was clear from the outset that it was unlikely to be successfully commercialised,” he said.

The PBMR was always intended to be sold outside South Africa and to do this there were challenges associated with getting the technology certified and meeting the complex regulatory and safety requirements of different countries, he said.

The scale of investment needed was just not worth it, given the low probability of commercial success, he said. It was just much cheaper to buy nuclear technology from someone else.

“But, even then, as we know, it is still going to cost twice the price of anything else out there,” he added, referring to the government’s plan to procure nuclear power, despite heated public debate over the costs when compared with the other options available to South Africa to meet baseload requirements.

Pursuing the PBMR in light of the enormous and proven opportunities being presented by renewable energies and gas would come at an enormous and unnecessary cost to South Africa and would be irrational,  he said.