All About Nuclear Power

Podcast Transcript

One of the most important and least understood sources of energy in the world today is nuclear power.

Nuclear power has an energy density tens of millions of times greater than fossil fuels and has one of the most impressive safety records of any energy source.

Yet, for decades, controversy has surrounded it and has hindered its adoption.

A new appreciation of the benefits of nuclear power might be changing that, however.

Learn more about nuclear power and how it works on this episode of Everything Everywhere Daily.

This episode has been a long time in the making. I’ve previously done episodes on wind, solar, geothermal, hydropower, oil, and coal, and now it’s time for nuclear to take its turn.

This episode will actually be a springboard for several future episodes, as there are so many related topics surrounding the technology and the history of nuclear power.

Nuclear power, as it exists today, involves getting energy from nuclear fission, or the splitting of atomic nuclei, almost always from the elements uranium or plutonium.

There are several attributes of nuclear power that have made it so attractive.

For starters, there is an enormous amount of energy that can be unleashed from the splitting of atoms.

1 kg of coal yields about 24 megajoules of energy when burned.

1 kg of oil yields roughly 42 megajoules of energy.

Per kilogram, natural gas holds about 55 megajoules..

By comparison, a kilogram of Uranium-235, the fissile isotope of Uranium, has 82 million megajoules if it is fully consumed.

That is over a million times more energy density than natural gas. Unlike fossil fuels, it doesn’t have any emissions.

Compared to renewable sources of energy like wind and solar, nuclear can provide a base load of power 24/7 and isn’t dependent on the weather. It also takes up much less space.

A 1-gigawatt nuclear plant takes up about 1.3 square miles, based on currently existing plants. Solar power takes up approximately 10 to 20 times the land to produce the same amount of electricity, and wind can take up as much as 100 times as much land.

Nuclear is also highly safe.

Coal has approximately 25 deaths per TWh of electricity produced.

Oil has 18 deaths per TWh.

Natural Gas has 3 deaths per TWh.

Hydropower has 1.3 deaths/TWh.

Wind has 0.04 deaths/TWh.

Nuclear has 0.03 deaths/TWh.

Solar has 0.02 deaths/TWh.

Despite everything that nuclear power has going for it, the percentage of electricity produced by nuclear power has dropped over the years. Today, the percentage of electricity produced by nuclear is about 10%, which is down from approximately 17% in the mid-1990s.

The history of nuclear power begins with the discovery of nuclear fission in 1938, when German scientists Otto Hahn and Fritz Strassmann found that bombarding uranium with neutrons caused it to split into smaller nuclei, releasing enormous amounts of energy. This breakthrough, explained theoretically by Lise Meitner and Otto Frisch, came just before the Second World War.

Unfortunately, given its timing just before the war, the first manifestment of nuclear fission was with weapons, not power generation. This association with destructive weapons gave nuclear power a negative connotation with many people.

In fact, many people still believe that a nuclear reactor can explode like an atomic bomb, which is literally impossible. A bomb requires over 90% fissile material, like U-235 or Pu-239. A nuclear reactor will usually only have between 3-5% fissile material.

After the war, scientists turned toward peaceful applications of nuclear energy. In 1951, the Experimental Breeder Reactor I in Idaho became the first reactor to generate usable electricity, producing enough power to light a few bulbs.

A few years later, in 1954, the Obninsk Nuclear Power Plant in the Soviet Union became the first nuclear power station to supply electricity to a grid. Britain soon followed with its Calder Hall station in 1956, marking the beginning of commercial nuclear power.

These very early reactors are known as First Generation reactors.

They were essentially experimental designs meant to demonstrate that nuclear energy could be used for electricity generation. Examples include the Shippingport Atomic Power Station in the United States and the Magnox reactors in the United Kingdom. They had relatively low efficiency, limited safety systems, and were not intended for long-term commercial use.

The 1970s saw the rise of what are known as Second Generation reactors.

They were designed with commercial power production in mind and emphasized standardization. Common types include Pressurized Water Reactors, Boiling Water Reactors, CANDU reactors, and Soviet RBMK reactors.

Safety features were improved, but primarily relied on active systems such as pumps, valves, and operator actions. These plants typically had a lifespan of 30–40 years, though many have been extended to 60 years with upgrades.

Most reactors still operating today belong to this generation.

The 1970s marked the largest construction boom in nuclear reactors.

However, as nuclear power plants proliferated, so too did public concern over safety, waste disposal, and the risks of radiation exposure. Several high-profile incidents fueled these anxieties. In 1966, the partial meltdown of the Fermi 1 breeder reactor near Detroit, although contained, brought home the possibility of nuclear accidents on American soil.

At the same time, the environmental movement was gaining strength, and books like Ralph Nader’s 1971 The Menace of Atomic Energy and growing activism by anti-nuclear groups kept safety issues in the public eye.

The result was a wave of new regulatory scrutiny in the 1970s. In the United States, the Atomic Energy Commission was dissolved in 1974, and its responsibilities were divided between two new agencies: the Nuclear Regulatory Commission, which focused solely on safety and licensing, and the Energy Research and Development Administration, which later became part of the Department of Energy.

This resulted in an explosion in regulations which had a corresponding effect on costs and construction time for new reactors.

The cumulative effect was dramatic. In the early 1970s, a nuclear plant could move from application to construction in as little as three to four years. By the end of the decade, the licensing process alone could take that long, while construction itself stretched into the 10–12 year range.

Regulatory requirements proliferated so quickly that plants approved under one set of standards often found themselves required to retrofit or redesign midway through construction, driving up costs and causing lengthy delays. Between 1970 and 1974, utilities placed orders for over 200 reactors, but by the late 1970s, nearly half of those projects were canceled, and almost none were completed on the original schedule or budget.

The first real blow to public perception of nuclear power took place in 1979.

An accident occurred on March 28, 1979, at the Three Mile Island nuclear power plant near Harrisburg, Pennsylvania. It began with a malfunction in the secondary cooling system that triggered the shutdown of the reactor. A relief valve in the primary cooling system stuck open, allowing coolant water to escape, but operators were unaware of the valve’s stuck position.

Believing the system was overfilled with water, they manually reduced the flow of emergency cooling, which made the problem worse.

What made the accident even bigger in the eyes of the public was that just twelve days earlier, a movie called ” China Syndrome” was released, which was about an accident at a nuclear reactor.

Oddly enough, while Three Mile Island is often called a disaster, no one was killed and no one was even injured.

In 1986, the world’s worst nuclear accident took place at the Chernobyl Reactor in the Soviet Union.

This will be the subject of a future episode, but what happened in Chernobyl was indeed bad, primarily due to an extremely poor Soviet reactor design, which didn’t exist anywhere else in the world.

Initial estimates that were reported in the news placed the death toll in the thousands. However, subsequent research by the World Health Organization and the United Nations Scientific Committee on the Effects of Atomic Radiation found that the actual impact of the disaster was far less than the original estimates.

Nonetheless, the damage to public perception was done.

Nuclear projects were halted or cut back significantly all over the world. Only a few places, such as France, continued to invest in nuclear power. Currently, France gets 70% of its electricity from nuclear, the highest percentage in the world.

As public perception was turning against nuclear power, advancements in technology and reactor design continued.

Third-generation reactors were developed. They feature passive safety systems that can shut down or cool the reactor without human intervention or external power, enhanced fuel technology, and designs meant for 60+ year lifespans.

With passive safety systems, something like Three Mile Island couldn’t happen.

Another thing that most people don’t realize about nuclear power is that not all reactors are the same. There are different types of reactors that work very differently.

There are fast and slow reactors, which regulate the speed of neutrons differently. There are high-pressure and high-temperature reactors that use different materials to transfer heat. There are different designs and even different fuels that can be used.

Just like with airplanes, advancements in technology have improved safety and efficiency over time.

There is a lot to be said about different reactor designs, which I’ll leave for a future episode, because understanding how each of them works requires more time.

I’ll close by discussing something that many of you are probably wondering about: nuclear waste.

Nuclear waste is often made out to be a major problem, yet it really isn’t. Unlike fossil fuels, which spray their waste into the environment, nuclear reactors can keep everything in one place. It is easy to track, store, and contain

To be sure, when material comes out of a reactor, it is dangerous. Very dangerous. Even short-term exposure could kill you.

However, if you remember back to my episode on radiation, the more radioactive something is, the shorter its half-life.

Waste is initially stored in water for a decade because water is particularly good at absorbing radiation. After ten years, the radioactivity of the waste is one percent of what it was when it came out of the reactor. From there, it is stored in dry casks, which are heavy, massive containers where it can naturally continue to cool down.

Within several hundred years, the radiation levels would be down to a level where, while you wouldn’t want any prolonged exposure, it wouldn’t be hazardous.

Finland has announced that it will be opening the world’s first deep geologic repository for waste in 2026. Waste will be safely stored deep beneath the surface where it can sit for up to 100,000 years.

However, there doesn’t have to be any nuclear waste, as almost all of it can be recycled.

That’s right. The entire nuclear waste problem can be solved because almost everything that comes out of a reactor is still usable for fuel. It could either be separated or used as fuel in what are known as breeder reactors.

Breeder reactors are special reactors that can turn fertile material, like U-238, into fissile material, like Pu-239. This allows the 99.3% of naturally occurring U-238 to be used as fuel rather than the much rarer U-235, which only makes up 0.7% natural Uranium.

When early nuclear researchers were designing reactors, they just assumed everyone would be using breeder reactors in the future because they made so much sense, but that never happened.

Not only can breeder reactors use nuclear waste as fuel, but they can also use fuel more efficiently, ensuring that the uranium reserves we have could potentially last for thousands of years.

Nuclear power has started to have a renaissance. More people are realizing that nuclear checks off so many boxes: it provides an enormous amount of base load energy, it isn’t intermittent, it doesn’t have any emissions, new designs have solved most of the safety issues, some proposed reactors can even be built at a cheaper cost, and the issue of waste is a very solvable problem.

Right now, the only country that is building reactors en masse is China. While many countries are reconsidering nuclear power, it will take a lot of political and economic willpower to restart construction projects.

Nuclear power was originally promised to be the power source of the 20th century. Hopefully, with a renewed commitment, it could finally fulfill its promise and become the power source of the 21st century.