Engineering360: "Study: The potential and challenges of microreactor technology"

Make them now, the world is already on fire.

Make them safe, safe enough to place in the company president's front yard.

Make the electricity free, we're running out of time to depend on profits.

Yes. And make the spent rods be stored on site until they decay to a safe level. And have an escrow account to pay for this storage.

The issues of safety are addressed as part of the design basis on most SMRs and certainly on all the Molten Salt designs. These are "walk-away" fail-safe. This means that they can be disconnected from external power and control at any point in the operation envelope and they will simply self-regulate to a safe, stable state.

The issues around "fuel rods" are non-existent for MSR designs since there are none. The fuel required for criticality is dissolved in the molten salt coolant. Additionally, most designs in the "Micro" power band have no fuel access on-site in any case; the entire "hot" module is sealed and delivered with the fuel for 20 to 30 years operation in place. After that the module is switched out and taken to the maker for full overhaul and re-refining of the coolant/fuel. By the way, one of the fuels under study is Thorium (Google or Wiki-search: LIFTR) (as opposed to Uranium or others) which, because it cannot be weaponised, is inherently not a risk in terms of proliferation.

The hacking risk is similarly present only at the level of, for example, turning the systems on and off. The configuration of the hardware simply does not allow the units to be forced into a potentially dangerous state. The worst-case for MSR's is that the liquid fuel/coolant overheats and melts a drain plug that is kept artificially cooled. This drains the fuel/coolant into a tank where a "poison" chemical is held which stops the heat-producing reaction.

Given all the "Red Flags" that are dropping lately, SMRs, and MSRs in particular, SHOULD be the object of targeted accelerated-development programs with the objective of having them be commercially available within 10 years. If there was ever something that was obviously a part of our infrastructure that needed money to make it happen, this is it.

The really sad thing is that all this was actually built and tested in the 60's. It was shut down when a strategic decision was made to restrict nuclear to large PWR reactors using enriched uranium fuels. This decision was largely driven by "National Security" interests and was underpinned by the military's need for a nuclear fuel processing industry to provide highly enriched Uranium and eventually Plutonium for nuclear weapons.

OK. Are you saying that at the end of the useful life of this reactor, there isn't ANY waste to be stored? With these, the many years of storage of spent nuclear fuel doesn't exist? If so, I'll promote them. With the need for water, there's going to be a lot of nuclear power plants getting sea water and making it potable. It's already started. The wastes from these plants poses a threat to the world. You are the first to state the MSR designs don't have nuclear wastes. Usually, the new nuclear designs state they minimize the waste. Minimizing the waste means it will build up more slowly over the years-like, 50000 years!!

Remains unproven that these machines are passively fail-safe nor have they been licensed by the Nuclear Regulatory Commission. The technical and operational issues are legion and have also not been proven as resolved.

In general, economic competitiveness lies with bigger and more efficient. The micro-reactors are going in exactly the opposite direction.