If the United States wants to reach net-zero greenhouse gas emissions by mid-century it will require building a new generation of nuclear power plants. Before that can happen, however, the nation must find a solution to the nuclear waste storage problem.

Expansion of renewable energy sources — solar, wind power, hydropower and thermal energy — will all play an important role in moving toward a future far less dependent on carbon. But the sun doesn’t always shine and the wind doesn’t always blow. Nuclear power provides sustained energy on a scale unmatched by other carbon-free technologies.

Take, for example, the two nuclear reactors at Millstone Power Station in Waterford. They account for 47% of the state’s electricity and 90% of its carbon-free electricity production. Though there are only 92 reactors operating, down from a peak of 112 reactors in 1990, they account for one-fifth of the nation’s electricity production.

It is inaccurate to say nuclear plants involve no carbon emissions. Mining and refining uranium ore to make reactor fuel requires large amounts of energy, as does construction of the plants. Presently, most of that energy comes from fossil fuels.

Once constructed, however, nuclear plants produce carbon-free energy. Construction of a new generation of plants should be less energy demanding.

Building a new generation of reactors will remain politically difficult. Given concerns about the potential for major accidents, any proposed plants would face opposition. These concerns can be overcome, however. A new generation of small modular reactors would depend on passive, gravity driven systems for cooling, rather than on pumps that can fail. The modular design would allow prefabricated units to be shipped and assembled on site. Less frequent refueling would mean less nuclear waste.

Independent studies, such as that by Decarb America, conclude that the nation cannot reach its carbon-reduction goals without nuclear power in the mix. The $1.2 trillion infrastructure plan that became law in 2021 includes $2.5 billion for advanced reactor design and demonstration projects.

Yet the lack of a solution for how to deal with nuclear waste, a problem far more political than technological, remains an impediment. A strong case cannot be made for new plants, which will produce more nuclear waste, until storage is addressed.

Spent nuclear fuel consists of long metal tubes containing reactor fuel pellets. They will produce dangerous levels of radiation for thousands of years. Long-term or permanent storage should take place in remote, geologically stable areas. Yucca Mountain in Nevada is such a place, and $12 billion collected from ratepayers was spent to prepare it to accept the waste. But the late Senator Majority Leader Harry Reid, a Nevada Democrat, used his considerable political pull to persuade President Obama to abandon the plan in 2010.

A new approach, backed by the bipartisan House Spent Nuclear Fuel Solutions Caucus, calls for financial incentives to entice host communities to accept construction of storage facilities, with the potential for multiple locations across the country. Connecticut Second District Rep. Joe Courtney, a Democrat, is a caucus member.

Estimates are that the process could take up to 15 years before any site starts accepting the waste. Connecticut’s House and Senate delegation must work to assure the initiative maintains sustained support. Further delays are unacceptable.

More unacceptable is for nuclear waste storage to continue long term at Millstone and more than 70 other operating and former nuclear plant properties, including where Connecticut Yankee once stood in Haddam Neck. While safe for the near future, leaving the waste for millennia on Long Island Sound and aside the Connecticut River would be the worst of options.

Excuse us for beating this drum, again. But this is a promise broken that needs to be set right. The Nuclear Policy Act, passed in 1982, mandated that the Department of Energy start accepting the waste for permanent storage by 1998. We cannot quietly accept this dereliction.

The Day editorial board meets with political, business and community leaders to formulate editorial viewpoints. It is composed of President and Publisher Timothy Dwyer, Executive Editor Izaskun E. Larraneta, Owen Poole, copy editor, and Lisa McGinley, retired deputy managing editor. The board operates independently from The Day newsroom.