Nuclear Facts

Question 1

About how much energy is 1 joule?

Answer 1

It is approximately the amount of energy that an apple falling off the table hits the floor with.

Question 2

What is a watt?

Answer 2

It is a rate for the number of joules per second. For example a 100W light bulb uses 100 joules of energy per second (creating light and heat). Think of rate as if it is a speedometer.

Question 3

What is a kilowatt-hour?

Answer 3

It is a rate of energy multiplied by time for an amount of energy accumulated. It is kilowatts time hours (not kilowatts per hour!), ie if you run 1000 W for one hour (or 3600 seconds) you get 3,600,000 Joules.

Question 4

How much energy did U.S. nuclear power plants produce in 2017?

Answer 4

805 billion kilowatt hours of electricity (or 805 GWe), enough to power 73 million homes.

Question 5

What power source creates the most clean energy in the U.S.?

Answer 5

Nuclear power. Historically, it has provided about 2/3rds of all clean energy. In 2017, it provided 56% of our total clean energy, with 21% produced by hydropower, 18% generated by wind, 4% came from solar photovoltaics and 1% from geothermal plants.

Question 6

Which type of energy is the most reliable?

Answer 6

Nuclear power operates on average at 92% of its Capacity Factor. In contrast, wind produces power on average on 37% of the time and solar only 27% of the time.

Question 7

How many U.S. States get power from nuclear energy?

Answer 7

There are 99 operating nuclear reactors generating power at about 60 plants in 30 states.

Question 8

What is the comparison of the amount of energy released from breaking a hydrocarbon bond versus the amount released from the fission of an atom of uranium?

Answer 8

Coal will release 2 electron volts of energy when a bond is broken. Uranium 235 releases 200,000,000 electron volts of energy from a single fission event.

Question 9

What are the equivalent volume amounts of coal, oil or gas that would equate to the energy contained in one standard uranium fuel pellet (measuring less than one inch by .5 inch)?

Answer 9

You would need 1 ton of coal, 120-150 gallons of oil (depending upon purity level), or 17,000 cubic feet of gas to produce as much as one pellet of uranium.

Question 10

What is the approximate volume of 1 ton of uranium?

Answer 10

Just over 13 gallons or 13 cubic feet.

Question 11

What is the cost of 1 ton of uranium?

Answer 11

Uranium prices have been low but the range of cost is between $50,000 and $100,000 per ton.

Question 12

How much coal would be needed to produce the same amount of energy as a ton of uranium?

Answer 12

1 ton of uranium generates the same energy as 2.4 million tons of the finest anthracite coal.

Question 13

What is the difference in cost between what you would pay for a ton or uranium and the equivalent amount of coal needed to be burned to produce the same amount of energy?

Answer 13

1 ton of uranium costs between $50,000 and $100,000. You need 2.4 million tons of high-quality coal to produce the same amount of energy, which would cost between $77 million and $103 million (including transportation)..

Question 14

What’s the amount of CO2 and other pollution released from fissioning 1 ton of uranium versus the equivalent amount of coal?

Answer 14

Fissioning uranium releases no CO2, whereas burning 2.4 million tons of coal releases about 6.9 million tons of CO2. Burning coal also releases lots of other toxic pollution into the air as well and produces both toxic and radioactive coal ash, that needs to be stored safely. Uranium releases nothing into the atmosphere except water vapor and the amount of waste produced is almost equivalent to the original amount of fuel used because fissioning does not burn the atom, it merely splits it into smaller parts (remember E=mc2).

Question 15

Approximately how much electricity is demanded globally on an annual basis (in terrawatt-hours)?

Answer 15

According to the International Energy Agency (IEA), global demand was ~20,100 TWh/year in 2013 and it has grown to ~23,000 TWh/year in 2018.

Question 16

How much has the electrification of transportation contributed to the growth of electricity in recent years?

Answer 16

Transportation electrification has been the fast-growing sector at 3.9% per year, since about 2011. With aggressive climate policies, (IEA’s 450 Scenario), EVs are projected to exceed nearly five times the reference level by 2040.

Question 17

What percentage of electricity generation was supplied by fossil fuels historically?

Answer 17

Historically, most of the energy for electricity, but it had declined to 67% by 2013.

Question 18

What is the current Paris Agreement goal?

Answer 18

The Paris Agreement’s central aim is to strengthen the global response to the threat of climate change by keeping a global temperature rise this century well below 2 degrees Celsius above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 degrees Celsius.

Question 19

What is the leading low-carbon generation technology in the US and OECD countries?

Answer 19

Nuclear fission (it’s also the second-largest in the world, just behind hydropower)

Question 20

How much nuclear power was generated by the global nuclear fleet in 2014?

Answer 20

2,500 TWh, with 78% of this occurring in OECD countries.

Question 21

When was nuclear’s most rapid period of growth?

Answer 21

1970 to 1995, since then it has been relatively stagnant. In the 1980s, 218 power reactors started up, an average of one every 17 days. These included 47 in the USA, 42 in France and 18 in Japan. These were fairly large – the average rated power was 923.5 MWe.

Question 22

What is the death rate for nuclear energy?

Answer 22

Nuclear’s death rate is .04/TWh, the lowest of all electricity generation sources globally.

Question 23

What is the average capacity factor of the US nuclear fleet?

Answer 23

Nuclear’s capacity has exceeded 90% since 1999. This compares to fossil’s 50 - 60% or renewable energy’s 25-35%.

Question 24

Describe the type of reactors which are predominantly used today.

Answer 24

These are water-cooled, operate at high coolant pressure and use uranium oxide fuel pellets contained in zirconium-based cladding. The uranium has U235 enrichment of less than 5%.

Question 25

What are nuclear’s primary challenges?

Answer 25

Economics, sustainability and perceived safety.

Question 26

Describe the U.S. fuel cycle.

Answer 26

Power reactors use a once-through fuel cycle, where the low-enriched uranium oxide fuel, where the U238 remains along with the fission products become “waste.” The U.S. is temporarily storing this waste, with a plan to put it into permanent, long-term storage.

Question 27

What type of fuel cycle is used in France?

Answer 27

France uses a mixed-oxide recycled nuclear fuel.

Question 28

When was the current nuclear technology originally developed?

Answer 28

Water-cooled technologies were originally developed in the 1950s and 1960s for powering nuclear submarines.

Question 29

What is the “moderator” used and what does it do?

Answer 29

The majority of water-cooled nuclear power reactors are also water-moderated, where moderation is the process of slowing neutrons down from the energy at which they are released to the energy most likely to cause fission, a key feature for the safety of the reactor.

Question 30

What are other moderators used with some water-cooled technologies?

Answer 30

The Reaktor Bolshoy Moshchnosti Kanalnyy (RBMK) from the former Soviet Union, and the Canada Deuterium Uranium reactor (CANDU), are moderated by graphite and deuterium oxide (“heavy water”), respectively.

Question 31

When was the accident at Fukushima Daiichi?

Answer 31

The Fukushima Daiichi accident occurred in March 2011.

Question 32

What was one of the responses to Fukushima?

Answer 32

A global R&D effort to enhance the safety of today’s water-cooled reactor technology by developing nuclear fuel and cladding materials with enhanced accident tolerance. These materials aim to increase high-temperature steam oxidation resistance versus the reference zirconium-based cladding materials that failed at Fukushima.

Question 33

Describe other efforts conducted to enhance the accident tolerance of existing water-cooled nuclear reactor technologies.

Answer 33

High-performance fuel materials that enhance thermal properties are under consideration, such as thermal diffusivity, and improved retention of radioactive fission products, aiming to increase safety in severe accidents. The development of new materials for the extreme environment of a nuclear reactor is aiming to solve various scientific, regulatory, and operational challenges.

Question 34

Describe some of the challenges facing the traditional nuclear industry in the U.S.

Answer 34

The industry is facing economic challenges: 1) Reactors are large to reduce overnight capital cost per kW installed (compared to smaller ones) but are too expensive and large to suit many regions; 2) Nuclear power is always on, inherently baseload, it can be difficult to integrate with renewables that are largely intermittent; 3) As a result of policies prioritizing renewables combined with de-regulated markets, nuclear must sometimes sell electricity at a loss; 4) Fossil fuels are relatively inexpensive fossil fuels, such as natural gas, since they don’t account for carbon or pollution. 5) The price of the new generation (Gen III) is too expensive, as there are too many safety/redundant systems; 6) Building reactors has involved “negative learning,” since each reactor is unique: 7) Almost all operating nuclear reactors in the United States will be retired in the 2035–2055 timeframe and it is not clear how they will be replaced.

Question 35

Describe a novel use of nuclear power.

Answer 35

There are opportunities for better integration of nuclear energy and renewables. One such opportunity is the nuclear hybrid energy system (NHES), a multi-input, multi-output system whereby a nuclear energy source operates synergistically and flexibly with renewable energy sources. Energy input streams in an NHES would include both nuclear energy (thermal or electricity) and other sources, such as wind, solar, or biofuels. The general idea is that when wind and solar are generating more electricity, the energy coming from the nuclear reactor is diverted to generate valuable coproducts. This is a particularly useful model: It removes the need for battery storage for renewables, which can have large capital costs and environmental impacts of their own, and valuable coproducts are created without GHG emissions.

Question 36

What industrial processes can utilize 300°C heat?

Answer 36

Desalination.

Question 37

What temperatures are anticipated from advanced high-temperature reactors?

Answer 37

Advanced high-temperature nuclear reactors produce >700°C degree heat.

Question 38

What is >700°C good for?

Answer 38

This is good for reducing industrial-sector GHG emissions via a thermally efficient and cost-effective integration with industrial processes requiring heat to accomplish their mission—heat that would otherwise most likely be generated by GHG-emitting technologies. Relevant industrial applications include process heat and hydrogen production for petrochemical and related industrial processes that require operating temperatures up to 900°C. Such an approach can be standalone or part of NHES.

Question 39

What is NHES?

Answer 39

Nuclear hybrid energy systems, a multi-input, multi-output system, which includes nuclear and other sources. The general idea is that when wind and solar are generating more electricity, the energy coming from the nuclear reactor is diverted to generate valuable coproducts.

Question 40

What are the findings of the recent US DOE Office of Nuclear Energy (DOE-NE) Advanced Demonstration and Test Reactor (ADTR) study developed to identify opportunities to expand the missions of nuclear energy beyond electricity production using nonwater-cooled reactor technologies?

Answer 40

ADTR Strategic objective opportunities include:

1. Deploy a high-temperature process heat application for industrial applications and electricity demonstration using an advanced reactor system, illustrating the potential for nuclear energy to reduce US industrial sector GHG emissions.
2. Demonstrate actinide management to extend natural resource utilization and reduce the burden of nuclear waste for future generations.
3. Deploy an engineering demonstration reactor for a less-mature reactor technology with the goal of increasing the overall system technology readiness level for the longer term.

Question 41

Which of the advanced reactor technologies provide flexible options for high-temperature process heat that achieves >700°C coolant-outlet temperatures?

Answer 41

These technologies may include:

1) the high-temperature gas-cooled reactor (HTGR),
2) liquid metal reactor (LMR), and
3) fluoride salt-cooled high-temperature reactor (FHR). LMRs can be either sodium- or lead-cooled. Typically, sodium-cooled LMRs have outlet temperatures of ∼500°C, although higher outlet temperatures (700°C) may eventually be possible in lead-cooled reactors if a cladding material with adequate corrosion resistance is found.

Question 42

What else does a high-temperature energy source accomplish?

Answer 42

Higher outlet temperatures enable a variety of process heat applications and also enhance conversion efficiency, flexibility and technology readiness. It is also valuable to be able to consume actinides: heavy elements that contribute to the amount and duration of radioactivity from used fuel.

Question 43

As to HTGRs or LMRs, which technology is preferrable?

Answer 43

LMR technologies are preferred, and in particular sodium-cooled fast reactors. These types of advanced reactors improve fuel cycle sustainability by enabling natural resource extension and burning long-lived actinides to reduce the burden of nuclear waste for future generations, further enhancing their benefits.

Question 44

Where is there a commercial LMR reactor?

Answer 44

In Russia, LMR technologies are being commercialized; the BN-800 commercial demonstration plant was successfully started in 2015 in a plutonium disposition mission.

Question 45

Where is HTGR being built?

Answer 45

TGR technologies are being deployed in China with two modular HTR-PM commercial demonstration units scheduled to come online in the near term, replacing coal-fired power plants. These examples are indicative of the promise of advanced reactor technologies in novel missions and show strong potential for near-term commercial deployment.

Question 46

What other AN technologies are there?

Answer 46

Other technologies, such as FHR or lead-cooled fast reactors (LFR), are potentially promising but have a lower technology readiness level than gas- and sodium-cooled technologies. The FHR and LFR technologies are in need of engineering demonstration reactors to prove their viability. There is a significant R&D program in China pursuing eventual deployment of FHR technology. All of these advanced reactor technologies may enable new markets that can reduce the energy sector’s GHG emissions and expand applications of nuclear energy, with HTGR and SFR technologies being most promising for deployment by 2035.

Question 47

What other promising potential development directions are there?

Answer 47

Another potential development area is closing the fuel cycle.

Question 48

What are the benefits of a closed fuel cycle?

Answer 48

The present operation strategy of the United States and most other nuclear nations is a once-through fuel cycle based on low-enriched uranium. The recently completed US DOE-NE Fuel Cycle Evaluation and Screening (E&S) identified fuel cycle options that offer enhanced performance and sustainability versus the present nuclear fuel cycle. The E&S evaluated all possible fuel cycles with respect to nine high-level criteria related to economic, environmental, safety, nonproliferation, security, and sustainability goals. The study found that, compared with today’s approach, advanced reactors and fuel cycles could:

1. Reduce waste generated by >10 times and reduce waste radiotoxicity by >10 times
2. Reduce fuel needed per unit electricity output by >100 times
3. Reduce land required and lifecycle CO2 emitted (already extremely low) by ∼2 times.

Question 49

Which fuel cycle offers the largest benefits?

Answer 49

The fuel cycles that offer the largest benefits versus the present US fuel cycle are those employing continuous recycling of uranium and either plutonium (U/Pu) or all transuranic elements (U/TRU) in fast neutron spectrum critical reactors. These fuel cycles are considered promising predominantly because they enable better natural resource utilization (>30% of the mined uranium is fissioned, compared to <1% in the present US once-through fuel cycle) and higher fuel burn-up (energy extracted per initial heavy metal mass). Fast spectrum systems have promising performance due to the larger number of fission neutrons released per neutron absorbed in the fuel relative to current systems. However, the potential transition from the present fuel cycle to a future fuel cycle represents a significant additional set of challenges.

Question 50

Which fuel cycles were not most promising and why?

Answer 50

Although the E&S considered nuclear fuel cycles based on thorium as well as externally driven systems (e.g., accelerator-driven systems and fission-fusion hybrids), those fuel cycles were not considered “most promising.” This is because irradiating U/Pu- or U/TRU-based fuels in the fast spectrum provides higher internal conversion capability than thorium-based fuels in either a thermal or fast spectrum configuration. Additionally, the application of critical reactors that are capable of sustaining fission without the need for an external source of neutrons lowers development risk, safety challenges, and overall costs compared to externally driven systems.

Question 51

How much power is a terawatt-hour equal to?

Answer 51

One terawatt-hour is roughly equivalent to the annual energy consumption of 12,400 US citizens.

Question 52

What are some of the other uses for nuclear power?

Answer 52

Nuclear batteries have been carried by deep space missions like Voyager and New Horizons. In the future, nuclear rockets could make deep space travel easier, faster and more enduring.

Question 53

What is NTP?

Answer 53

In 1961, NASA and the Atomic Energy Commission worked together on the idea of nuclear thermal propulsion, or NTP. This was pioneered by Werner von Braun, who hoped that human missions would be flying to Mars in the 1980s, on the wings of nuclear rockets (did not happen, tho!)