Fusion is Great—But Fission Can’t Wait

 

Readers of this blog know of my advocacy of nuclear power—in particular fission power. Fission power still faces several hurdles including those of financing and long-term storage of spent fuel. On more than one occasion I have been asked if instead of pushing forward with fission power we should wait for fusion power, which is making substantial advances. Indeed, the past few years have brought exciting breakthroughs in fusion energy. In this post, I will review these advances and summarize the remaining technical challenges. Those interested in a more thorough discussion may want to refer to this ADL report.

First though, a brief recap of the physics of fusion processes. Light nuclei have less binding energy per nucleon than mid-sized nuclei (like helium or iron). When small nuclei fuse, some mass is converted into energy via Einstein’s equation, E=mc², releasing vast amounts of energy Nuclear fusion is the process where two light atomic nuclei (typically isotopes of hydrogen, like deuterium (D) and tritium (T)) combine to form a heavier nucleus (like helium), releasing tremendous amounts of energy in the process.

D+T→⁴He + n

What makes the process difficult to achieve is that the atoms must be brought very close to each other. Normally, the repulsive coulombic forces exerted by negatively charged electron clouds surrounding the nucleus prevent atoms from getting closer than a few picometers (10^-12 m). The strong nuclear forces which hold the protons and neutrons together become operative at very close distances, femtometer (10^-15 m) scale. If the atoms are heated to very high temperatures, millions of degrees, the electrons are stripped away from the nuclei producing a plasma—essentially, ionized gas. At these high temperatures, the nuclei have sufficient kinetic energy to overcome the even higher repulsion as they approach each other closer and the collide to produce fusion. This is the process that powers the sun and stars.

On earth, this was first achieved by raising the temperature of fuel hydrogen to millions of degrees from the heat of a plutonium bomb to trigger the fusion of hydrogen. Although we can release energy of fusion in the H-bomb, releasing fusion energy in a controlled manner for producing power would require confining and sustaining a plasma while continuously feeding in fuel and extracting the released energy.

Two main approaches of confining plasma are (a) magnetic and (b) inertial. The former uses magnetic coils (Tokomak and Stellerator) arranged in a donut shape to steer the plasma away from the walls and circulating within it at a high speed. Using several different heating techniques such as ohmic, RF heating, or injecting neutral particles, the plasma is heated to 100 million degrees (Kelvin) to achieve fusion. For reference, the temperature in the core of the sun is around 15 million K. The magnets keep the plasma away from the walls of the containing vessel. Inertial confinement relies on instantly heating a pellet of fuel gases with multiple lasers.

The National Ignition Facility (NIF) uses the inertial confinement approach. It dumped 2.05 MJ of energy from 192 lasers firing simultaneously on a gold cylinder containing D and T to achieve fusion. The experiment produced in 3.15 MJ demonstrating a major scientific breakthrough—a net energy gain with Q = 1.5. This announcement unleashed a frenzy of activity to develop fusion power. Private companies like Commonwealth Fusion Systems (CFS) are racing ahead, with SPARC—a compact, high-field tokamak—set to demonstrate net energy gain by 2027. Meanwhile, Helion Energy signed a power purchase agreement with Microsoft, betting on fusion-powered electricity by 2028.

Achieving Q > 1, is a remarkable feat! The NIF reported getting 50% more energy than dumped into the fuel pellet by the lasers. For steady power generation, the desired value of Q should be 50 or more. Further, this calculation does not include the 500 MJ of electricity that went into powering the lasers. Overall process is far from being energy neutral, let alone a power producer. Among the many remaining challenges is figuring out the process for replacing the fuel-filled cylinders one after another in the precise location and be able to fire the lasers at repeatedly. At present there is no pathway for this approach to be used for power production.

Magnetic confinement approach offers pathways for continuous fuel feeding and energy extraction, but it has yet to demonstrate net energy gain. Another issue that will need addressing is the supply of tritium. Tritium is an unstable isotope with a half-life of 12 years. There are no deposits of tritium that can be mined or extracted; it must be produced prior to use either by neutron activation of ⁶Li or in nuclear reactors that use heavy water as a moderator. Most of these processes are accompanied by the release of fast-moving neutrons that cannot be confined by magnetic fields, and they can damage the containing vessel. There is another scheme for fusion that relies on a stable isotope of boron, ¹¹B, for fuel and (TAE Technologies) and does not involve release of fast-moving neutrons. It involves bombarding boron nuclei with protons and the fusion process results in three alpha particles:

¹¹B +p→ 3 ⁴He

The higher nuclear charge of boron (six protons) means that the incoming proton has a substantially higher barrier of coulombic repulsion before fusion can occur. The required temperature for this process is a billion degrees!

Despite recent progress, commercial fusion remains decades away. Even optimistic forecasts place the first grid-scale plants in the 2040s. The engineering hurdles—plasma confinement, tritium breeding, and material durability—are immense. So, while we chase the "holy grail" of fusion, we can’t afford to ignore the proven, low-carbon power source we already have, namely nuclear fission. Modern reactors are safer, more efficient, and essential for decarbonization. Countries like France show how fission can deliver 70% of electricity with near-zero emissions. Small Modular Reactors (SMRs) with lower startup costs offer faster deployment and flexibility. With the World Bank now reversing its policy against financing nuclear power project there is a real opportunity to rapidly expand global nuclear power generation.

Thank you Mr. Banga!

While researching for my book, A Cubic Mile of Oil, I realized the necessity for nuclear power to meet global energy needs. Ever since, I have been an active proponent for nuclear power. Some of you may have seen my open letters on this blog to leaders and decision makers advocating for nuclear power. No wonder I was very pleased to read the news that the World Bank has finally lifted its ban on funding nuclear power. I reversed its policy and will now finance nuclear energy projects should host countries choose to do so. 

https://www.world-nuclear-news.org/articles/world-bank-agrees-to-end-ban-on-funding-nuclear-energy

The World Needs Nuclear Power

 

I recently learned about Notebook LM from Google. It is an AI tool with an ability to cull information from a variety of sources like documents, presentations, videos, etc. and generating briefing papers and podcasts. I gave it try by submitting some of my hour-plus long video presentations and was quite pleased with the short podcasts it generated. Next, I tried feeding it six of my blog posts, all related to nuclear power, and I am posting the resulting podcast here. Take a listen and let me know your thoughts.

Understanding Energy: Three video presentations

Since my retirement, I have been trying to foster a public debate on energy and climate issues. To that end I had given several presentations that are still available on YouTube. I am sharing links to three of them: the first one is a general discussion of global energy and climate change; the second one deals with nuclear power and why I believe it is an option we must embrace; and the third deals with enabling technologies like hydrogen and carbon capture and sequestration (CCS) that may be required to reduce greenhouse gas emissions. Together, the three talks are a primer to inform the general public of the challenges we face and possible solutions. 

I made these presentations to the Science for the Bored group of mostly retired scientists. Each video begins with a general chit-chat as we wait for people to join in. My 45-min presentation begins around 7 min, and is followed by an interesting, albeit lengthy, Q&A session. Please feel free use the videos in your classes or share them with your associates.

1. Replacing Cubic Miles of Oil:  https://youtu.be/LWhVfYin_ds?si=hl4h0ddZXEJ0zdx8

2. Arguing for Nuclear Power: https://youtu.be/jl6sy8d-Lsc?si=I9rZUefzokkNTr33

3. Ancillary Technologies for Getting to Zero: https://youtu.be/48DOct2CQpo?si=gcH9N8gWN6WM52YH

Note:

I recently saw Nuclear Now, a film by Oliver Stone that is available on YouTube. It is based on a book, A Bright Future, by Joshua Goldstein and Stephan Qvist, which I had read and admired when it first came out about five years ago. The movie is sufficiently different, but very good. I highly recommend it.

Open Letter to Mr. Ajay Banga, President, The World Bank Group

 

Dear Mr. Banga,

Congratulations on being appointed the President of the World Bank. I watched your interview with Fareed Zakaria of June 11, 2023, and am prompted to write this letter requesting that you reconsider the policy forbidding investments in nuclear power. 

You grew up in India and your experience informs you of the absolute need for adequate energy for people around the world. Like you, I too grew up in India. I too witnessed the improvements in the quality of life and health when charcoal- or dung-fired clay pots were replaced by gas stoves, or when electrical bulbs replaced kerosene lamps. As one of your predecessors, Dr. Jim-Yong Kim, pointed out in an interview that the enormous progress made during the last 25 years lifted over a billion people out of poverty. He could foresee lifting another billion in the not-too-distant future. Earlier progress was made on the backs of coal and oil. Can we afford to do the same to help the next billion?

I am glad you called for an energy transition from coal-to-gas-to-renewables. Yet, calls for divestment from fossil fuel companies to mitigate climate change only reduces the supply of gas, raising the cost of fuel and most adversely hurting the poor. There is no social justice in that.

The absence of nuclear power in the coal-to-gas-to-renewables transition you discuss is deeply concerning to me. Wind and solar are intermittent energy sources and when you consider the cost of storage at scale, they are not cheap—not in direct dollars, nor in their environmental footprint when accounting for all the mining required for the materials. If we rely only on wind and solar to provide the required clean energy, we will have to increase mining activities manifold and encroach on natural habitats, further exacerbating the risk of pandemics.

Nuclear power can produce vast quantities of carbon-free energy. It has resulted in the fewest fatalities per unit of energy delivered than any other system, including wind and solar. It also has the smallest environmental footprint. It is unfortunate that multinational agencies like the World Bank and the International Finance Corporation have a policy against supporting deployment of nuclear power plants. Their reluctance is based principally on our unfounded fear of radiation, reinforced by decades of fearmongering by environmental activists.

I ask you to reconsider the policy against supporting nuclear power projects. In concert with quickly deployable wind and solar technologies, nuclear power can provide the requisite base power without the need for inefficient gas-fired power plants. Should you have any questions, please contact me.

Respectfully,

Ripudaman

********************************

Ripudaman Malhotra

Fellow, American Chemical Society

Misguided Disinvestment

 

The call for divesting from fossil companies is getting louder by the day with more environmental activists, celebrities, religious organizations, universities, pension funds managers, institutional investors and legislatures joining in the chorus. The fossil fuel divestment movement, which began in the early 2010s, seeks to encourage individuals and institutions to remove their investments from companies that are involved in the production and use of fossil fuels, such as coal, oil, and natural gas. Though I agree with the goal of transitioning away from fossil energy, I believe that the disinvestment is misguided. Not only does it not reduce carbon emissions, it also exacerbates social injustice. Let me explain.

The movement believes that climate change, which is largely being caused by our use of fossil fuels, is an existential threat and argues for a quick transition to clean fuels. The logic behind divestment goes something like this. It would send a strong signal to fossil fuel companies that there is growing concern in the public about the impacts of their activities, which would send a message to governments and other investors that the risks associated with fossil fuel investments are increasing. It would pressure them into adopting more sustainable practices or transition to cleaner energy sources or face the financial risk of holding stranded assets. Divestment can help reduce this financial risk for investors. For individuals and organizations that are committed to environmental and social responsibility, divestment from fossil fuels can be a way to align their investments with their values.

The environmental activists have influenced several states in the United States into considering legislation for divestment from fossil fuel companies. In 2015, California passed a law that requires the state's public employee pension funds to divest from coal companies. This was followed by New York, which in 2020 introduced legislation that would require the state pension fund to divest from fossil fuels by 2023. After that, many states like Massachusetts, Maryland, Oregon, and Vermont introduced similar legislation. The divestment has had the effect of making it harder for the oil and gas companies to raise funds for projects as lenders are viewing the loans riskier. As a result, the industry has cut back on drilling and used its earnings to buy back stock.

About 3 billion people in the world today are living with energy poverty, which results in low life-expectancy, high infant mortality, high death rates during childbirth, malnutrition, unsanitary conditions, inadequate infrastructure, and general impoverishment. Children, mostly girls, spend their days collecting fuel and fetching water from distant wells or ponds. The loss of human potential is staggering. How many of these children could have grown up to be teachers, engineers, doctors, leaders, entrepreneurs, lawyers, etc.

Indoor cooking over animal dung or wood exposes children to more pollutants and further impacts their health. The health benefits for them in switching to gas are enormous, and efforts should be made to furnish them with steady supplies of pipelined gas or LPG cylinders.

The lack of investments in drilling has made this task more difficult, particularly in view of the global disruptions in the supply of natural gas following the invasion of Ukraine by Russia. The US could be in a better place to supply the world with liquefied natural gas and ensure energy security. The situation in Europe could have been much dire the past winter but for the mild weather. We have time to gear up for the next winter. It is ironic that in view of rapidly changing climate we are rushing to install climate-dependent energy sources.

I recognize that natural gas is still a fossil fuel, whose burning leads to carbon emissions. I would just point out that the reason US greenhouse gas emissions have declined is basically a result of switching from coal to natural gas. We could have reduced the emissions even further, if instead of investing in wind and solar projects (20% availability), which we back up with natural gas fired plants of 30% efficiency, we had installed fewer, base-load, combined-cycle natural gas power plants with efficiencies of 55% or higher. It would also have saved us the hassle of integrating intermittent wind and solar power with the grid.

This is not the time to cut investments in oil and gas production. Unless the demand for their use comes down, greenhouse gas emissions will not decrease. Calls for divestment only assuage one’s guilt for using products and services made possible with fossil energy.

A Tribute to President Jimmy Carter

 

President Carter is currently under hospice care. Before it is all too late and rendered moot by life's irreversible course, I want to express my appreciation for the man who is an inspiration to me. 

Dear President Carter,

 

I was a chemistry graduate student in 1978 when I first heard your call for a moral equivalent of war to gain energy independence, in the wake of oil embargoes by OPEC. Caricaturists called this your “meow” moment. It was more a “roar” to me, and I enlisted as a foot soldier in your army in this “moral equivalent of war.” I worked most of my career on energy-related issues: at first the problem was rather simple. We lacked liquid fuels to meet our transportation needs, but we had plenty of coal. Coal had been converted to liquids. 

 

The technology for liquefying coal was developed in early twentieth century in Germany, but it was very expensive. It was also deployed by Germany during the war and later by South Africa to mitigate international sanctions, but the costs needed to come down substantially for coal-derived liquids to compete with oil in a free economy. The energy challenge has since become a whole lot tougher with the recognition of the climate change engendered by burning fossil fuels for energy. Today, we seek energy from sources that are also environmentally benign and compatible with the goals of sustainability.

 

Working in the field of energy made me acutely aware of the looming energy crisis humanity is facing, and the need for an informed public debate on the choices we have to make. About fifteen years ago, I joined my colleagues Hew Crane and Ed Kinderman to write a book that could be a citizens’ guide to energy. Admittedly, energy is a difficult subject to discuss, but it is made even more so by the plethora of units and mind numbing multipliers of billions, trillions, and quadrillions.

 

While waiting in the gas lines in 1973, Hew had come to the realization that annual global consumption of oil was then approaching one cubic mile, and a cubic mile of oil seemed to be a good unit to describe energy from all sources. At a conference in January 2016, physicist Amory Lovins brought to my attention that you had arrived at a similar conclusion, but that as a navy man he preferred cubic nautical miles. I did some searching of old documents from your days in the White House and came across a memo dated April 18, 1977, by Stu Eizenstat converting barrels to cubic miles. There were also some hand scribbled calculations on the page, probably by you. The thought made a tingle ran up my spine. 

 

Energy is not the only area in which you have inspired me. Your moral rectitude and tireless pursuit of social justice have been just as inspiring. Your efforts at resolving conflicts, promoting peace through free and fair elections, and fighting diseases are all laudable. The way you have dedicated your life to public service after the presidency stands as a shining example of how to live out one’s retirement.

 

Wishing you comfort and peace in your remaining days.