Sample White Paper – Mjolnir Power Systems

This white paper is about a real technology, but not a real company.

Thorium – Providing Power Now and for Our Next Thousand Years

Human civilization depends on safe, inexpensive electrical power free of harm to the health of humans or our ecosystem.

Increased world GDP (well-being) is linked directly to increased use of power. We have made great progress in generating and using power, but, much of the world still lives in deep poverty. Also, current methods of generating power severely harm human health and the environment.

  • Fossil fuels power much of our world, but they pollute air and water, and drilling for them and mining them harms the landscape.

  • Hydroelectric power can only be used in places with rivers, and it disrupts the flow of rivers and interferes with fish migrations. Also, in one terrible case in China, it led to flooding killing hundreds of thousands.

  • Solar and wind power are limitless, but are not available at all times, kill large numbers of birds and bats, and need large areas of land and huge amounts of construction.

Nuclear power is clean, very safe, and reliable. But, as used now, it needs costly preparation of fuels, and complicated and expensive handling of waste. Nuclear can be made even safer.

How can we make more, safe, power (especially electrical power) available? By using thorium as fuel in molten-salt reactors. Liquid fluoride thorium reactors (LFTR’s) can produce electrical power and process heat for industry.

Thorium is nearly as common as lead. Unlike uranium, thorium needs no isotopic refinement to be used as fuel.

Using molten salt reactors greatly simplifies waste disposal and improves safety.

This can be done at a cost per kilowatt-hour as low as coal, using well-tested technology.

<sidebar>Uranium mined from the earth has two isotopes, U-238 (99.3%) and U-235 (0.7%). Only U-235 is used as fuel, so mined uranium has to be highly refined to remove U-238.

Thorium mined from the earth has only one isotope, so no costly refinement is needed.


The Challenge

This paper discusses how leading companies are designing molten salt reactors (MSR’s) using thorium, to quickly and safely begin power generation, and also make very valuable fission products.

The results? Inexpensive electrical power, process heat, desalinated water, and fission products that can fight cancer and power deep-space satellites.

In the following pages, we take a closer look at how humanity has met its power needs so far; look at the downsides of pre-nuclear and current nuclear solutions; review the usefulness of thorium as a nearly inexhaustible source of power; and examine the benefits of using thorium as a fuel in liquid form, in an MSR. Finally, we compare the capital and operating costs of using thorium in LFTR’s with other ways of generating power.

According to T. J. Garrett (Department of Atmospheric Sciences, University of Utah), world GDP (wealth) is linked directly to the rate of use of power. According to the United Nations, in mid-2017, the population of Earth is about 7.5 billion. 836 million people live in extreme poverty. And, the population is expected to reach 11.2 billion by 2100.

<Graphic: graph showing linear relationship between (a) energy consumption per person and (b) GDP>

Humanity desperately needs more power per person, for many more people.

Current Practice

Pre-nuclear Sources of Energy

Before the industrial revolution, the source of power was mostly food; with some use of wood, coal, dung, and whale oil; and local use of water or wind power.

The steam engine was revolutionary, and enabled massive use of coal and oil.

The invention of internal-combustion engines and electrical generators made fossil fuels even more useful, and led to massive use of hydroelectric power.


Pre-nuclear sources and uses of power come with costs.

Burning coal for power requires environmentally damaging mining, and use of both coal and fossil fuel pollutes air and water. The U.N. estimates that over one million people die each year due to particulate pollution from coal, and this is just one of coal’s health risks.

Hydroelectric power is limited to areas with rivers, harms wildlife, and has led, in China, to over 200,000 deaths from flooding.

Solar and wind power are inexhaustible, but can only be used in certain places and can only produce power some of the time. They need vast areas of land, kill huge numbers of birds and bats, and require large amounts of manufacturing and construction.

Our Current Nuclear Source of Energy

Nuclear power

  • delivers over one million times as much power per pound of fuel as oil or coal,

  • is highly reliable,

  • requires very little space, and

  • does not pollute our air or water.

However, our current practice of using uranium in solid fuel pellets in water-cooled reactors has many drawbacks.

Uranium found in nature is a mixture of isotopes: U-238 (99.3%) and U-235 (0.7%). U-235 is the isotope needed for power generation. Separating useful amounts of U-235 needs costly refinement, and leaves large amounts of depleted uranium, which needs careful disposal.

Current nuclear power plants use uranium in solid form, as ceramic pellets encased in metal fuel rods. Gaseous byproducts, such as xenon, form cavities in fuel pellets, making the fuel rod useless. Some other byproducts are extremely radioactive. These could be removed by reprocessing the fuel pellets, but this is costly and complicated, and is not done in the United States. Currently, in the United States (according to the Nuclear Regulatory Commission), waste is stored, without being reprocessed, at over 68 locations.

Further, current nuclear power plants use piped water to gather heat from the hot core. This heat is carried to a turbine that generates electricity. Water normally boils at 100 degrees centigrade, but in reactors water is pressurized at up to 150 atmospheres. This is done to keep it from boiling at a working temperature of 325 degrees centigrade. Leaks at this pressure are mechanical explosions, and can destroy equipment and buildings, release radioactive steam, and kill anyone nearby. Also, this steam would instantly expand thousands of times, carrying radioactive debris, and would need containment and cleanup.

A Better Solution

Thorium, used in molten salt reactors, is the answer. What are the advantages of using thorium as fuel in a molten salt reactor?

  • Thorium is practically inexhaustible.

  • Thorium is safe.

  • Thorium is perfectly suited for use in molten-salt reactors (MSR’s).

  • MSR’s are a tested technology.

  • MSR’s are inherently safer than solid-fuel water-cooled reactors.

  • MSR’s produce far less waste than solid-fuel, water-cooled reactors.

  • Thorium, used in MSR’s, can provide energy at lower cost than coal.

Thorium is Abundant.

Thorium is about 7.2 parts per million of the Earth’s crust. This is only slightly rarer than lead, and about three times as common as uranium. Further, all natural thorium is the useful isotope Th-232. Only 0.7 percent of natural uranium is the isotope useful as fuel, U-235. So, useful thorium is more than four hundred times as common as useful uranium. Uranium needs to be enriched to raise its concentration of U-235, by removing U-238. This removed uranium must be handled as waste. Thorium needs no isotopic refinement, so no waste is produced.

<Graphic: How much thorium, vs. how much uranium, with uranium broken down between U-235 and U-238>

Thorium is a common byproduct of current mining of rare earths. Rare earths have many uses; for instance, neodymium is widely used in consumer and military electronics, such as to make ultra-strong magnets. Large amounts of thorium are currently stored as waste from mining, and the current price of thorium is about fifty dollars per kilogram. Given the power density of thorium, the cost of thorium is only a tiny part of the cost of delivering power.

In fact, right now, the United States has enough thorium (buried as “waste” in Nevada) to generate more electrical power than the U.S. uses in three years. Kirk Sorensen of Flibe Energy estimates that generating electricity for the current population of Earth, with each person using as much electricity as an average resident of the U.S., would need 1500 metric tons of thorium per year. The International Atomic Energy Agency estimates that the world has readily available reserves of 1.725 million tons. At 1500 metric tons per year, this would last 1150 years. Exploration and improvements in mining technology will make more thorium reserves readily available.

Thorium is safe.

Naturally-occurring thorium has a half-life of 14.05 billion years. Contrary to a common misunderstanding, longer half-lives are worse. A shorter half-life means that the energy in a material is released more quickly, which is more dangerous. For instance, U-235 has a half-life of 70.4 million years (20 times shorter than thorium) U-238 has a half-life of 4.47 billion years (about one third that of thorium). Even naturally occurring potassium-40 (a small fraction of all natural potassium; even in bananas!) is eight times as radioactive as thorium.

Thorium can be used in molten-salt reactors.

Although uranium was used in the Molten Salt Reactor Experiment conducted at Oak Ridge National Laboratory in Tennessee, one finding of the experiment was that enough neutrons were produced to use thorium as the fuel source.

Thorium also can be used in MSR’s, and can be used as fuel with neutrons in the thermal spectrum. (“Thermal spectrum” means that neutrons are moving relatively slowly.)

Uranium 238 cannot be used as fuel in the thermal spectrum, but can be in the “fast spectrum”. Unfortunately, use of fast spectrum technology requires much more radioactive material in a reactor. Also, using U-238 as fuel leads to more byproducts heavier than plutonium. These materials complicate storage of nuclear waste.

<Graphic: 60’s era photo of staff at MSRE>

Molten-salt reactors are proven.

Molten salt reactors were thoroughly tested at Oak Ridge National Laboratory. The Aircraft Reactor Experiment (1954) proved that MSR’s worked. The following Molten Salt Reactor Experiment (1965-69) proved that MSR’s could be used safely and for long periods, and that the number of neutrons produced would enable use of thorium as fuel.

Molten-salt reactors are safer than solid-fuel water-cooled reactors.

Using molten salt rather than water to carry heat from the core to a power-generating turbine is much safer. Water must be highly pressurized to be kept liquid at useful temperatures. Molten salts do not need additional pressure to remain gaseous. Leaks of molten salt would not result in a steam explosion, and no radioactive steam and debris would be released. A leak would result only in a drip, rather than an explosion, and the salt would simply re-freeze.

<Graphic: frozen salt plug>

<Graphic: comparison (not to scale) of sizes of piping, walls, and containment required>

Molten-salt reactors produce far less waste than solid-fueled reactors.

Nuclear reactions produce some gaseous byproducts, and these deform solid fuel pellets and metal fuel rods. Also, radiation degrades some uranium oxide into uranium metal and oxygen, and this oxygen can degrade fuel rods. Because of these problems, fuel rods are removed from service after twelve to eighteen months, with only part of the uranium in the fuel rods having been consumed.

Molten salt reactors do not have fuel rods, so none are deformed. So, unlike solid fuel reactors, which use less than one percent of mined uranium before rods have to be removed, thorium, used in a molten salt reactor, can be completely consumed.

With fuel carried in a liquid, such as molten salt, gaseous fission byproducts, such as xenon, can simply bubble out rather than causing pockets in solid fuel pellets. Many other fission byproducts, are extremely useful (in fighting cancer, or in providing power to satellites) but cannot be extracted efficiently from solid fuel pellets, so they are treated as waste. These materials can be economically extracted from liquid fuels through chemical and mechanical means, and would not be waste.

<Graphic: comparison of sizes of waste streams, calling out useful isotopes recoverable from molten salt>

Thorium, used in molten salt reactors, can provide energy at lower cost than coal.

According to Energy from Thorium ( the median capital cost (of five studies) of construction of a molten salt reactor, per Watt, is $1.92. For comparison, this is well lower than $2.30 for coal.

Nuclear fuel is much more energy-dense than fossil fuels. So, the operating cost of fuel per kilowatt-hour from thorium in an MSR would be around four thousandths of a cent. This is about one thousand times lower than coal. Total costs of delivered power would be about three cents per kilowatt-hour (Update of the MIT 2003 Future of Nuclear Power, 2009).

Expected Results

Shifting to nuclear power from thorium in molten salt reactors will have many benefits:

  • Huge amounts of new power can be brought online quickly.

  • Replacing coal power with nuclear power will clean our air and water.

  • Much less mining, which damages our landscape, will be needed.

  • Using thorium rather than uranium will dramatically reduce complexity and cost of refinement of ores into fuel. This will eliminate radioactive waste from this step.

  • Use of thorium will also reduce the production of plutonium and other transuranics. This will radically simplifying storage of fission byproducts.

  • Cancer-killing bismuth-213 will be produced as a byproduct, and can be extracted.

  • Reactors and buildings will have much lower construction costs and be safer.

  • Other precious byproducts will be able to be economically extracted, rather than being treated as expensive waste.


  • Thorium is so abundant that it can provide power for thousands of years.

  • Thorium, unlike uranium, requires no refinement, and so has no related wastes.

  • Thorium is perfectly suited for use in molten-salt reactors. These are inherently safer than water-cooled reactors. They can operate at normal pressure, and pose no risk of mechanical explosion or release of radioactive steam.

  • Liquid fuels simplify processing of fission byproducts; allow extraction of valuable byproducts; and allow the most dangerous byproducts to be burned as fuel.

  • Thorium, used in molten salt reactors, can provide power at lower cost than any other source, including coal and natural gas.

How to Decide

When considering strategies for generating power for the advancement of civilization, there are important features of power sources to consider.

Is the energy source cost-effective?

True costs of solar and wind power are extremely high. These costs are hidden through subsidies. Thorium in MSR’s can beat all other sources in providing low-cost power.

What non-monetary costs are there?

Solar, wind, and hydro power all interfere with our ecosystem. Solar farms burn birds and interfere with aviation. Wind power requires vast areas of land and huge amounts of construction, and kills huge numbers of birds and bats. Dams interfere with migrations of wildlife.

Manufacturing equipment for solar and wind power produces large amounts of industrial waste.

Hydropower can also lead to catastrophic failures, leading to many deaths.

Coal pollutes air terribly, leading annually to over one million deaths from related diseases, and poisons grounds and waterways. Further, coal mining is very dangerous.

Thorium is easily mined, does not interfere with the ecosystem, and does not pollute.

Is the fuel readily available?

Thorium is so abundant in the Earth’s crust that every country could be energy-independent at a consumption rate equal to the current consumption rate of the United States. Already, each year, enough thorium is dug up, and becomes tailings of rare earths mining, to provide power for the world many times over.

Does the use of the power source create large amounts of waste?

Thorium requires no isotopic refinement (as does uranium) and so produces no related waste. Use of molten salt reactors dramatically reduces the volume, and duration of high radioactivity, of waste, and allows complete use of fuel.

Is the power generation system safe?

Molten salt reactors cannot melt down. “Melting up” is actually a required step in the production of power. Molten salt reactors do not require pressurization as do water-cooled reactors. This prevents steam explosions and release of radioactive steam. Electrical power failures at a power plant would lead, through gravity, to the draining, cooling, and freezing of the fuel.

Considering these questions –

Thorium, used in molten salt reactors, uniquely meets all these criteria.

Next Step

If you are ready to move forward with a program to provide enough electrical power to bring all of humanity up to a civilized standard of living, and provide that power for a millennium or more, we look forward to working with you!

We will discuss the requirements for building a proof-of-concept reactor. This will extend the learnings from the Molten Salt Reactor Experiment. We will also discuss the requirements for building the first few of our Hammer Class production civilian reactors. These will provide power for human civilization.

You can take a useful, extremely profitable part!

About Mjolnir Power Systems

Founded in 2017, Mjolnir Power Systems is developing the leading thorium-fueled molten salt reactors for generation of electrical power and production of high-value radio-isotopes to ensure that Earth has enough power to run civilization on-planet and explore the rest of the solar system.

Mjolnir designs and will build modular systems for companies and governments that need safe, clean, reliable, inexpensive energy; radio-medicines; and space fuel. With world-leading technology and expertise, Mjolnir accelerates “time-to-power” for customers worldwide. Mjolnir Power Systems, which received funding from YoyoCap Partners in 2017, is headquartered in Atlanta with offices in Provo, Utah and Tokyo.

Additional information about Mjolnir Power Systems is available at or by calling 575-347-1599, or by contacting us by email at


Sidebar 1

Bare sustenance requires about 200 Watts per person. Civilization requires much more power, most of it electrical.

At present, humanity uses about 16,000 gigawatts, or about 2100 watts per person. The United States uses about 10 kilowatts per person, with 4.3% of the world’s population.

To bring energy availability for all humans to the level of the U.S. would require generation of a total of 75,000 gigawatts, an increase of 59,000 gigawatts.

If, as the United Nations Department of Economic and Social Affairs predicts, the world population increases to 11.2 billion by 2100, a total of 112,000 gigawatts (an increase from the present of 96,000 gigawatts) will be required to provide power for all at the rate currently provided in the United States.

Sidebar 2

The Story of the ARE, MSRE, Plutonium

Alvin Weinberg helped develop the light water reactor during World War 2 in order to produce plutonium for bombs. He saw risks in the use of solid fuel with water as the heat transport fluid. Weinberg proposed research into liquid-fueled reactors for generation of electrical power for civilian use. To get funding, Weinberg proposed development of a nuclear-powered bomber. He then directed the Aircraft Reactor Experiment (ARE), using molten salt to carry dissolved fuel, at Oak Ridge in 1954.

The ARE was successful. This led to the follow-on Molten Salt Reactor Experiment (MSRE), which validated use of an MSR to generate power for civilian use.

However, the Molten Salt Reactor Experiment was shut down by the U.S. government. This was done to concentrate resources on development of fast-breeder plutonium reactors, for production of plutonium for weapons, and with a hope to use fast breeders. Fast breeders could use a (U-238)-(neptunium-239)-(plutonium-239) cycle similar to the (Th-232)-(protactinium-233)-(U-233) cycle. However, fast breeders have had many dangerous failures.

Sidebar 3

“Our economic goal is to achieve a cost of electrical energy averaged over the life of the power station to be no more than that from burning fossil fuels at the same location. Past studies have shown a potential for the molten salt reactor to be somewhat lower in cost of electricity than both coal and LWRs. There are several reasons for substantial cost savings: low pressure operation, low operations and maintenance costs, lack of fuel fabrication, easy fuel handling, low fissile inventory…” (Ralph Moir and Edward Teller)