Clean energy is at a critical turning point, and wind and solar may not be enough
Last week at the North American Leaders’ Summit featuring President Obama, Canadian Prime Minister Justin Trudeau and Mexican President Enrique Pena Nieto, the three nations announced a goal of generating 50 percent of North America’s electricity from “clean” sources by 2025. It’s a laudable goal, but it naturally raises a question — how exactly, in the United States, do we get there?
A closer look at what the White House and its counterparts actually mean by this proposal shows that for the United States the goal relies on far more than an ongoing boom in wind and solar. It rests substantially on hydropower and energy efficiency gains and also includes under the definition of “clean energy” two technologies that are less than popular in the environmental movement — nuclear energy and carbon capture and storage. Yet it is hard to say that nuclear and CCS are booming in this country; it would be more accurate to say that both are struggling at the moment.
Thus, the new goal raises a serious question of precisely how we are transitioning toward a future in which far more (and, eventually, all) of our electricity is generated without emissions of carbon dioxide to the atmosphere — and how different types of power generation will slice up this new pie.
Let’s start in the easy place. Wind and solar are growing in the United States (and elsewhere), and a doubling of their U.S. generating capacity (or even greater growth than that) by 2025 isn’t hard to imagine. We know we are going to be getting a lot more of our future electricity from wind and solar than we do now.
That’s a very good thing — but even a doubling of wind and solar likely wouldn’t be enough to get the United States to 50 percent clean electricity by 2025. The trouble is that in 2015, these sources contributed a little more than 5 percent of all U.S. electricity. They are starting from a relatively low level of penetration, albeit with high growth rates.
For just this reason, nuclear’s inclusion in the North American plan is a mathematical necessity — it provides about 20 percent of the United States’ overall electricity and a far larger percentage of its carbon-free power. The centrality of nuclear arises in part because unlike wind and solar deployments, nuclear plants generate electricity almost continuously, often generating above 90 percent of their maximum capacity in a year. Solar, in contrast, is much more intermittent. So is wind.
However, unlike wind and solar, the nuclear industry is not in great shape right now in the United States and hardly looks poised for much growth out to 2025.
In June the large California utility Pacific Gas and Electric announced plans — in the form of an agreement with labor and environmental groups — to close the Diablo Canyon nuclear plant, whose two reactors provide a stunning 9 percent of the entire state’s energy, by the year 2025. The vast amount of electricity currently generated by Diablo Canyon would be replaced, the company said, with wind, solar, batteries and more energy efficiency.
It’s just the latest indicator that the future is cloudy for nuclear. Five U.S. reactors closed in 2013 and 2014, and Diablo Canyon joins the list of numerous other planned closures in coming years.
The United States is also expected to add five new nuclear reactors in coming years — one, Watts Bar 2 in Tennessee, is already generating electricity and has sent some to the grid — but it seems poised to end up with roughly the same or perhaps less nuclear generation overall in 2025. Whether the situation worsens even further for nuclear will depend on economic factors, like the price of natural gas, that will be hard to forecast.
[It’s the first new U.S. nuclear reactor in decades. And climate change has made that a very big deal]
And then there’s carbon capture and storage — which basically refers to techniques to keep the carbon emissions from coal- or gas-fired electricity generation, or other industrial processes, from reaching the atmosphere and instead channel them into reservoirs in the ground. Sometimes, that also involves using the carbon dioxide to make a little extra income along the way through enhanced oil recovery.