The U.S. Department of Energy has committed about $450 million to two Small Modular Nuclear Reactor (SMR) designs over the last year-and-half — one by Oregon’s NuScale and the other by North Carolina’s Babcock and Wilcox — that essentially shrink traditional reactors to between roughly 3 percent and 15 percent of their normal output (the future of at least one of those reactors has grown questionable now that B and W has revealed that funding difficulties could hamper its development).
There are molten salt reactor companies including Terrestrial Energy, Thorium Tech Solution and Transatomic Power.
Pebble bed reactors companies are Steenkampskraal Thorium, X-Energy and Northern Nuclear.
SmartPlanet provides a detailed update on the General Atomics (GA) Energy Multiplier Module (EM²) reactor.
GA is innovating new materials, getting the efficiency way up, simplifying the design and getting the cost into the competitive range.
GA is developing a Brayton cycle to convert heat to electricity at 53% versus 28 to 34 percent for regular steam turbines. In a four-module plant (1.06GW), one point of efficiency is worth a billion dollars in revenue over the life of the plant. 53% efficiency means $19 billion dollars more than a 34% efficient plant.
GA’s design is a 265-megawatt (electric) sized reactor, with a fuel cycle lifetime of 30-plus years.
General Atomics EM2 Economics
Large nuclear reactors produce electricity at 11 cents (U.S.) per kilowatt hour [not older reactors which have completely amortized their build cost which are cheaper], the EM² will deliver at 6.5 cent.
The cladding material is a breakthrough which can remain intact to over 2,000 degrees Celsius. General Atomics recently completed 9 months of successful, rudimentary testing of the material in Tennessee at Oak Ridge National Laboratory’s High Flux Isotope Reactor (HFIR), a test reactor that has a high neutron flux and can emulate the “fast spectrum” that EM² will deploy (EM² will not slow down neutrons the way today’s “moderated” reactors do).
Breakthrough design to handle the helium problem for Brayton Cycle
GA has engineered a Brayton cycle method that will funnel the helium straight into the turbine without first transferring it and less efficiently converting it to steam, the way conventional reactors do with Rankine cycle turbines. That method will deliver a 48 percent efficient heat-to-electricity conversion rate. GA will then boost the overall number to 53 percent by adding a Rankine cycle that captures otherwise lost heat.
GA is working with nuclear engineering companies Chicago Bridge and Iron (through CB and I’s acquisition of the Shaw Group) and Mitsubishi Heavy Industries; government supporters include the U.S. state of Mississippi.
SOURCE – Smartplanet, General Atomics