Nuclear promise and Jordan’s energy strategy

There were some confused stories in the press recently hinting that Jordan will be constructing a High Temperature Gas-Cooled Reactor (HTGR). The fact is that Jordan, among many countries, is considering and assessing HTGRs into their energy mix, because of the many favourable features of such class of reactors, including diverse applications (electricity generation, process heat, desalination and hydrogen production), inherent safety features and elimination of core melt, small footprint and reduction of the emergency zone and minimising the water cooling consumption and possibility of dry cooling.

But, some observers and “experts” claim that “operational experience with high temperature reactors that have been constructed in the United States and Germany have been disappointing, with reactors being prone to a variety of failures and being shut down ahead of targeted lifetimes”. This statement is very general and incorrect in many ways. There are about 14 HTGR running very well in the UK. The focus in the next generation reactor is on a specific subset of these reactors, mainly the pebble bed with helium cooled, which actually operated very successfully in Germany but were shut down for purely political reasons.

Normally, progress in the world occurs through learning from past operational experiences and this is exactly what the new vendors of new HTGRs are doing.

As an example, the US passed in 2005 the Energy Policy Act, mandating the construction and operation of a HTGR by 2021. This law was passed after a multiyear study by national experts on what future nuclear technologies should be developed. As a result of the act, US Congress chose to develop the so-called Next-Generation Nuclear Plant, which was to be an HTGR-designed to produce process heat for hydrogen production.

The subset of HTGRs that Jordan is interested in uses graphite as moderator and helium gas as coolant. The fuel is tristructural-isotropic particle type coated with several carbon and other layers, to keep its mechanical integrity and retain fission gases, and is embedded in a tennis ball size graphite ball. The use of such fuel significantly enhances the safety of the reactor; from the fundamental nuclear physics it is inherently safe under normal operation and accident conditions.

HTGRs are known and proven to be “inherently safe” compared to other types of reactors. The probability of core damage under all accident conditions is close to zero. Under these conditions, the maximum fuel temperature is kept below 1,600°C; much lower than the temperature at which core damage occurs. In the unlikely case of air or water ingress, the HTGRs are designed in a way that the temperature of the fuel will never exceed the damage limit. In case of air ingress, there is a passive system which injects Nitrogen to prevent graphite-air reaction. In case of water ingress, two safety systems will work to minimise the amount of water entering the core.

HTGRs use less water for cooling, per MWe, than a typical large reactor because it has higher efficiency of about 44 per cent. Considering its very high steam temperature and other steam conditions, similar to conventional plants, this feature allows the use of dry cooling, which is a plus for Jordan.

Regarding the cost of fuel, it is true that the fuel manufacturing cost is more expensive for
HTGRs compared to other reactors, but this is misleading. Looking at the overall fuel cycle, HTGRs have higher burnup than standard reactors, generating 30 per cent more electricity for the same amount of fuel.

Despite many detractors, Jordan should continue its pursuit of nuclear energy and assessment of the options.  Globally, nuclear energy is the most competitive stable option for generating electricity as has been proven over the last 60 years. Nothing can compete with nuclear energy in the long run. No intermittency, no disruptions in generation, no need for storage technology, over 90 per cent availability, minimal risk exposure to fuel price fluctuations, 60 years of generation, attributes that PV or gas generators could never attain. Today, nuclear power plants built 25-30 years ago, the maximum life of a PV power plant, generate electricity at 3 cents/kWh and will do so for another 30 years, and single handedly subsidise an electricity grid.

As decision-makers in Jordan are contemplating revision of the energy strategy, we leave them with few recommendations:

Jordan should assess the real total cost of energy alternatives, not just market value, accounting for system costs, social costs and environmental impacts or externalities, and choose a generation portfolio among nuclear power, fossil power and renewables that provide grid reliability and energy security, imposes a minimum economic burden on consumers, secures a low carbon future and preserves water resources.

Jordan should carefully design institutional arrangements when encouraging the use of renewables that avoid market distortion and minimise economic burden to consumers.

Jordan should assess the growing number of market experiments that are being conducted in other countries, like Germany and the United States, to learn from the difficult experiences these counties are now facing with their electricity supplies.

The writer is manager of the Jordan Nuclear Power Plant Project at the Jordan Atomic Energy Commission