factsheet, January 1997

 A future for the HTR?

A consortium of the Dutch Energy Research Foundation (ECN), Stork Nucon, Royal Institute for Testing Electrical Materials Arnhem (KEMA), the Techniical University Delft and Engineering Firm Romawa does research on the possibilities of the High Temperature Reactor (HTR). Last summer (1996) a presentation was given to commercial companies, that led to a wait and see attitude. Today (16-1-97) the results of a pre-feasibility study will be presented. The Incogen-HTR is a concept with a number of disadvantages.

 Foreign countries
Research on the HTR has been ended mostly. The German Siemens finished 1991 its research when the reactor did not seem to be accepted after an investment of about 2 billion DM. In the US the House of Representatives stopped funding the General Atomics HTR in 1995. The HTR has a development time of 30 years now without having reached the status of commercial reactor. Only prototype and demonstration reactors were realised. As an ECN report mentions: "Was it a good idea to work on a 30 year old concept without having new ideas?"  The HTR researchs seems to end this year (1997) as the Ministry of Economic Affairs will stop funding.

Main risk of the HTR is the presence of graphite and the absence of a concrete containment. As the Chernobyl disaster showed, the consequences of a graphite fire are grave. In the HTR a scenario is possible when water or air enters the coolant circuit due to leakage of a heat-exchanger. In its design the HTR has no containment that protects against the release of radionuclides in case of an accident. The containment also serves as a protection for outside influences like a crasheing airplane or a gas explosion. The US Nuclear Regulatory Agency NRC doubted the absence of a containment already in 1988.  Doubtfull are statements by the ECN that no contingency plan would be necessary for an HTR.  A serious accident is never to be excluded.

The HTR technology has its risk for the spread of nuclear weapons technology. In most designs is worked with higly enriched uranium. That is suitable in nuclear weapons. In the fuel additional plutonium is formed. Plutonium is extremely toxic and from an HTR good suitable for weapons. Some designs are based on a thorium as fuel where fissionable uranium-233 is formed. Like plutonium this uranium is also suitable for nuclear weapons. The HTR fuel cycle has to be implemented with stringent security measures to prevent misuse of technology and material. But international conventions like the Non-Proliferation-Treaty NPT will not give sufficient protection. The secret weapons programms of NPT members Iraq and North Korea showed the failing of controls.

 Economic feasibility
It is doubted wether the HTR will be economic feasible. In an ECN study  only one model could compete with a combined heat-electricity gas fired plant, but only when the gas prices would double. This model is based on thorium fuel. Worldwide there is only little experience with thorium fuel. The economic feasability of the other 3 concepts, based on uranium fuel, is doubted due to high investment costs.

The main problem of nuclear energy, the production of nuclear waste, will not be resolved with the HTR. The production of waste starts with uranium mining. The ECN states: "Uranium mining brings severe damage to the landscape. .. The radiological risk of mining waste is one of the greatest of the uranium cycle and affects people that have little profits of this cyclus."  The waste will remian radioactive for millions of years and there is no outlook on a safe disposal method.

Reprocessing results in the release of radioactivity and the increase of the amount of waste. Reprocessing plants like La Hague (F) and Sellafield (UK) are known as serious polluters of the oceans. The reporcessing of HTR fuel will result in the release of activated graphite (Carbon-14), called a dominating risk of reprocessing.  With reprocessing plutonium or uranium-233 will be extracted, a risk for proliferation.

The Incogen project seems to be a new initiative of the Unit Nuclear of ECN to cope with the threath of continuing reductions of its budget. The government policy is getting more and more unkind of nuclear energy. No new decisions will be taken on new nuclear reactors and several governmental studies don't see further options for it.  It is more realistic te spend money on renewable energy. These are more clean, safer and cheaper than the THR.

This background information was written by Laka Foundation (originally published in Dutch, 16 January 1997).