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How Does a Solar Eclipse Impact the Electric Grid?

Millions of Americans traveled long distances in hopes of getting a front-row seat for the dance of the heavens today, watching the moon eclipse the sun, from Portland, Oregon, to Charleston, South Carolina. Hundreds more had spent months preparing for an odd complication of the event: the very sudden loss of up to 9,000 megawatts as solar panels were cast into shadow, and then its very quick return. The lost production is the equivalent of about fifteen good-sized coal plants.

How do you keep the lights on when the sun suddenly goes out? The loss and rebound of generation is much larger than the system usually faces, but experts made some serious advance preparation, and were hopeful  largely because of the diversity of generators. Nuclear plants continue to provide the backbone of the system, and generators running on natural gas were called on to power up quickly, and as the sun reappeared, power down even faster.

Such diversity is important because the system has to function throu…
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Packing for Mars? Don’t forget the nuclear reactor.

Did you see the movie The Martian? The hero, Mark Watney, an astronaut given up for dead by NASA, uses a radioisotope thermoelectric generator (RTG), a sort-of "space battery," to keep warm during his trek across Mars.
The movie is science fiction but these devices are real- NASA has been using RTGs to power satellites for nearly forty years, and they've been used on major trips to the moon and other planets. But NASA recently announced plans to use nuclear power in a different way- one that hasn't been fully attempted in fifty years. 
The RTGs like Mark Watney’s harness the heat from passive radioactive decay and produce a few hundred watts of electricity, which on Earth would be enough to run a handful of household appliances. But a mission to Mars would require far more power. Now, NASA is working on a reactor that splits atoms, as reactors on Earth do, to make 100 times more electricity than an RTG. The initial plan calls for 40 kilowatts, which on Earth would meet…

Why Nuclear Plant Closures Are a Crisis for Small Town USA

Nuclear plants occupy an unusual spot in the towns where they operate: integral but so much in the background that they may seem almost invisible. But when they close, it can be like the earth shifting underfoot., the Gannett newspaper that covers the Lower Hudson Valley in New York, took a look around at the experience of towns where reactors have closed, because the Indian Point reactors in Buchanan are scheduled to be shut down under an agreement with Gov. Mario Cuomo.

From sea to shining sea, it was dismal. It wasn’t just the plant employees who were hurt. The losses of hundreds of jobs, tens of millions of dollars in payrolls and millions in property taxes depressed whole towns and surrounding areas. For example:

Vernon, Vermont, home to Vermont Yankee for more than 40 years, had to cut its municipal budget in half. The town closed its police department and let the county take over; the youth sports teams lost their volunteer coaches, and Vernon Elementary School lost th…

21 Experts Debunk a Radical Claim about Renewable Energy

Energy experts are at war over a radical assertion that by mid-century the United States will be able to meet all its energy needs with wind, solar and hydro power.

The claim was made in 2015 by four academic researchers, led by Mark Z. Jacobson, for the continental United States, and it asserts that those renewables will replace not just the coal and natural gas used to make electricity, but also the gasoline and diesel that run cars and trucks, and the gas used in home heating. The paper is regularly cited by environmentalists who claim that the current fleet of U.S. nuclear reactors could close without any consequences to grid reliability.

But last week, a group of prominent researchers, some from Stanford and UC-Berkeley, and others from the National Oceanographic and Atmospheric Administration, Carnegie Mellon and other mainstream organizations, published a second paper that said that while they support the expanded use of renewables, Professor Jacobson et al. were dreaming.

One o…

Missing the Point about Pennsylvania’s Nuclear Plants

A group that includes oil and gas companies in Pennsylvania released a study on Monday that argues that twenty years ago, planners underestimated the value of nuclear plants in the electricity market. According to the group, that means the state should now let the plants close.


The question confronting the state now isn’t what the companies that owned the reactors at the time of de-regulation got or didn’t get. It’s not a question of whether they were profitable in the '80s, '90s and '00s. It’s about now. Business works by looking at the present and making projections about the future.

Is losing the nuclear plants what’s best for the state going forward?

Pennsylvania needs clean air. It needs jobs. And it needs protection against over-reliance on a single fuel source.

What the reactors need is recognition of all the value they provide. The electricity market is depressed, and if electricity is treated as a simple commodity, with no regard for its benefit to clean air o…

TMI Cancer Study: Radiation, Health and Questionable Claims

Researchers at the Penn State College of Medicine recently published a study claiming that analysis of thyroid tumors showed tissue differences, based on where the patient lived. People who lived near Three Mile Island at the time of the 1979 accident had tumors more likely to have come from radiation exposure than people who developed thyroid cancer while living elsewhere, according to the researchers.

Science is advanced by experts who publish new findings, and readers who then evaluate the conclusions and how they fit into the existing body of knowledge. We welcome all contributions to knowledge. But scientific studies should be read with care, so their claims can be understood, and so we can determine how the findings fit with what was previously understood. And these findings don’t fit.

Despite what a reader might assume from a news headline, this paper does not assert that Three Mile Island is the cause of any cancers. It goes off in a new direction, in ways that may not be obvi…

Why America Needs the MOX Facility

If Isaiah had been a nuclear engineer, he’d have loved this project. And the Trump Administration should too, despite the proposal to eliminate it in the FY 2018 budget.

The project is a massive factory near Aiken, S.C., that will take plutonium from the government’s arsenal and turn it into fuel for civilian power reactors. The plutonium, made by the United States during the Cold War in a competition with the Soviet Union, is now surplus, and the United States and the Russian Federation jointly agreed to reduce their stocks, to reduce the chance of its use in weapons. Over two thousand construction workers, technicians and engineers are at work to enable the transformation.

Carrying Isaiah’s “swords into plowshares” vision into the nuclear field did not originate with plutonium. In 1993, the United States and Russia began a 20-year program to take weapons-grade uranium out of the Russian inventory, dilute it to levels appropriate for civilian power plants, and then use it to produce…