Nuclear Is Not The Answer

Among the most frustrating parts of discussions about the human predicament is the widespread belief that nuclear energy is the answer. It’s not. If money were not a consideration—but it is—nuclear plants just can’t be built fast enough to make much of a difference.

The only solution to climate change and the ecological crisis is to dramatically reduce energy consumption. All energy consumption—not just fossil fuels. That was the core message of a talk that I gave at the University of Texas Energy Symposium in September called Substituting Renewable Energy for Fossil Fuels is a Doomsday Stratagem.

The first question from the audience began with this statement, “A one-child policy is something we should all be espousing and allowing people to take their lives after age 60 if they want without ruling it a suicide. Things like that should be absolutely in the policy list.”

My reply was to do what seems right to you but recognize that these kinds of things will make no difference in the window of urgency for the earth’s environmental crises. And so it goes with most “solutions” to our predicament.

I’m not naive. I have no expectation that society will reduce energy consumption either voluntarily or by government mandate but it is the only realistic solution. The problem for most people is that it’s just not the right solution. The right solution is one that allows society to continue on its current path with a few relatively comfortable tweaks like substituting renewable energy for fossil fuels or designing a circular economy. People will follow any mirage rather than acknowledging the truth because the truth is too hard.

Nuclear energy is not a mirage but neither is it the answer to our energy and environmental problems. It’s a proven energy source unlike many mirage technologies. Nuclear fusion, salt reactors and SMRs (small nuclear modules) are frontier technologies that are unlikely to have much effect in the critical decades ahead. That doesn’t diminish their potential to make a difference. Just not in the current window of urgency.

Nuclear’s greatest limitation is that its only practical use today is to generate electric power. Electricity is only 20% of global energy use so nuclear and renewable energy do little to affect total consumption. Their greatest potential benefit is to reduce coal use.

IEA’s recently published World Energy Outlook 2023 indicates that electric power will increase over the next few decades but only to about 30% of total world energy consumption (Figure 1). Nuclear’s contribution is expected to remain flat at about 2% of total energy use through 2050.

Percentages, however, can be misleading. The percent nuclear is flat because renewables, solar and wind are projected to increase so much. Total nuclear generation will increase 1,671 TWh (Terrawatt hours) (+62%) from 2022 to 2050 in IEA’s Stated Policies scenario shown in Figure 1. That will probably be used mainly as base load support for intermittent solar and wind electric power.

EIA’s International Energy Outlook 2023 is less optimistic that electric power will increase than in the IEA projection but agrees that nuclear will only account for about 2% of delivered energy consumption through 2050 (Figure 2). Nuclear output will increase but not as a percentage.

These projections are almost certainly wrong but they are notionally reasonable.

Let’s think about the constraints on new nuclear generation without considering cost. Eight new nuclear plants were completed worldwide in 2022. An average of nine new plants per year must be completed to go from 2,682 terrawatt hours in 2022 to IEA’s estimate of 4,353 terawatt hours of generation in 2050. In order to double that, an additional 24 plants must be added each year for a total annual addition of 33 new plants per year. Building four times the number of plants completed in 2022 every year for the next 27 years would move nuclear to 4% of total energy supply. That’s not going to happen. And even if it did, 4% is not going to change our predicament.

Some may argue that Gen III+ reactors and small modular reactors (SMR) may make the doubling of nuclear output more feasible. Perhaps but those are frontier technologies that are unlikely to make an appreciable difference in the energy landscape over the next few decades. Nor do they change the hard truth that an awful lot of capacity has to be built just to double nuclear generation to 4%.

Nuclear power is an important part of the energy landscape and its importance will increase moving forward. It’s just not the answer.

Most of the energy and the environment debate is about climate change and finding ways to replace fossil fuels with lower-carbon forms of energy. That is what I have presented above. This is a narrow view of the human predicament that Jan Konietzko calls Carbon Tunnel Vision (Figure 3). A broader perspective is needed that includes energy, economics, population, ecology and human behavior.

Climate change is not the biggest problem facing the world. It is a symptom of the much larger problem of overshoot. That means that humans are using natural resources and polluting at rates beyond the planet’s capacity to recover. The main cause of overshoot is the extraordinary growth of human population made possible by fossil energy.

Overshoot is more difficult to dispute than climate change—the destruction of rainforests, the population decline of other species, the pollution of land, river and seas, the acidification of the oceans, and loss of fisheries and coral reefs. These are not part of any natural process and human activity is clearly responsible.

Technology, unfortunately, is no more a solution to climate change, overshoot or the human predicament that it was the primary cause for human prosperity.

A broader view of our predicament shows that global CO₂ levels will probably flatten as population growth slows (Figure 4). The bad news is that CO₂ levels of about 500 parts per million by 2080 suggest a transition to a nearly ice-free world similar to Earth in the Late Miocene Epoch 15 million years ago. By the late 20th century, it is likely that the world oceans will be largely ice-free in the summer. The implications for rising sea level and its effect on human coastal cities and coastal plain rice production are frightening.

An even broader view of the human predicament includes the material requirements for the technologies that are being used to limit carbon emissions. As society attempts to reduce its carbon footprint, we should be equally mindful of how this may affect its material footprint on the planet. There will be unanticipated consequences that our energy transition initiative has not considered.

Electric cars, solar panels, wind turbines, batteries and nuclear power require substantial mineral, metal and chemical inputs. The projected growth in demand for these materials will put increased pressure on the planet’s natural resources and will require substantial use of fossil energy for their extraction, transport, manufacture, and distribution.

This perspective indicates that fossil fuels are not the biggest component of society’s material footprint. They account for only 17% of society’s effect on the planet (Figure 5). Non-metallic minerals account for 47%, biomass for 27% and metal ores for 10%.

Society’s material footprint and global GDP correlate almost perfectly with an R² of  0.99 (Figure 6). This indicates that continued economic growth will result in ever-greater levels of society’s material footprint. That in turn suggests that an energy transition will have little net effect on society’s material footprint on the planet.

A still broader view considers the ecological footprint of the human enterprise on the earth. This is a measure of the human impact on the environment and nature’s capacity to support people and their economies. Society has been exceeding nature’s carrying capacity by an average of 71% since 2010.

Carbon emissions and the overshooting of planetary boundaries are unlikely to decrease as long as energy consumption, world GDP and population continue to increase (Figure 7). The interrelationship of these factors with the degradation of Earth’s ecosystem means that there are no solutions without a structural change in all of these factors as a starting point. This implies that a civilizational paradigm shift is required.

When I  talk to people about energy, the environment and the human predicament, they want me to help them understand what society can do to solve the problems that I describe. They are often frustrated when I tell them that it’s not that simple. Focusing on one part of the predicament like emissions or nuclear power may feel satisfying but simply shifts most of the problem somewhere else.

Energy is the organizing principle that connects all of the elements of earth systems and human society. If we use less energy, emissions will decrease. Energy consumption and GDP have an almost perfect correlation so less energy use will reduce economic growth. Less energy will force a reduction in population. Lower economic growth, fewer emissions and a smaller population will result in a reduced human footprint on the environment. It’s logical but not simple. It won’t happen voluntarily so it will be imposed by circumstances. It will be traumatic.

Making adjustments like substituting renewable energy for fossil fuels is like removing pieces from a Jenga tower. We’re pulling out pieces but don’t think it will collapse. In the Jenga game, the tower always collapses.

The answer is to end the delusion that we can substitute one form of energy for another, and that it will solve all our problems. Nuclear power is part of the solution but it’s not the answer. Let’s acknowledge the complexity. The answer is to use less energy. It’s time to get honest about the human predicament.