Guest editorial: Nuclear can supply carbon-free power, but waste must be managed permanently and safely

This is a guest editorial by Mitch Jacoby, C&EN’s executive editor for physical sciences.

For years, I have said that one of the biggest perks of being a science reporter is that I am always learning about fascinating scientific topics. One of those topics is nuclear reactor technology, a subject I began covering nearly 20 years ago.

Two just-published stories in C&EN rekindled my fascination and reminded me of the challenges associated with using nuclear power to generate electricity. One of the stories, last week’s cover by Craig Bettenhausen, describes a new design of nuclear power plants known as small modular reactors. Just a fraction of the size and cost of standard nuclear reactors, these smaller ones could supply large chemical plants and manufacturing facilities with an on-site, off-grid source of fossil fuel–free electricity and heat.

The other story, by Priyanka Runwal in this week’s issue, is about treating and disposing of wastewater from nuclear power plants (page 23). Plant operators routinely process the water, reduce the concentration of tritium and other radioactive elements to trace levels, then dilute the water and discharge it into rivers and oceans. The process is tightly regulated to meet safety standards, and radiation levels are extremely low. Even so, environmentalists worry about potential harm to people and the environment, and they protest the discharge process.

Both stories remind me of conversations I have had over the years with friends, all of whom are highly educated. I explain that human activity pumps a tremendous amount of carbon dioxide into the atmosphere, roughly 40 billion metric tons in 2021. I point out that atmospheric levels of CO₂ are rising, despite international efforts to reduce emissions of the greenhouse gas.

My friends agree that lowering CO₂ emissions is important. But when I tell them that nuclear power can help, because unlike coal- and gas-fired power plants, nuclear power plants don’t emit CO₂, they react as though I have suggested doing something horrible.

Many people hear the words nuclear or radioactive and automatically think of disaster. Plenty of people are unaware that nuclear power plants have been generating electricity reliably and safely for decades. These friends are surprised to learn that today, nearly 20% of the electricity in the US comes from nuclear plants. I guess if you don’t live near one or take an active interest in the subject, it’s not on your radar. Yet roughly 440 commercial plants run 24/7 in 30 countries. And according to the World Nuclear Association (WNA), 60 more are under construction.

People’s fears are warranted. Nuclear power comes with huge potential hazards and risks. And the world has witnessed some awful nuclear disasters, such as the ones that occurred in 1986 at Chernobyl and in 2011 at the Fukushima Daiichi power station. But for the most part, safety measures and regulations have worked to keep nuclear plants operating without incident.

The real challenge, it seems to me, is managing nuclear waste, which is complicated by people’s fear of it. In the US, more than 90,000 metric tons of highly radioactive waste sits awaiting permanent disposal—and has been sitting for many years.

Finland, Switzerland, and other countries in Europe, are planning deep geological repositories to safely and permanently store nuclear waste. Finland has been constructing its site for 20 years and is set to begin using it next year.

In the US, detailed plans were developed to store the country’s waste in a repository beneath Yucca Mountain in Nevada. But that proposal goes in and out of favor with changes in the country’s leadership. And so for now, radioactive waste accumulates mainly where it’s generated—at the power plants and processing facilities. Clearly that situation is unsustainable.

Nuclear reactors have the potential to supply a substantial portion of the world’s electricity without emitting CO₂. According to the WNA, nuclear currently provides about one-quarter of the world’s low-carbon power. It could provide more. But to do so, the US and other countries need to follow Finland’s lead and permanently manage their waste.

Views expressed on this page are those of the author and not necessarily those of ACS.