accidents

New approaches to nuclear power

November 18, 2024 By EarthWise 1 Comment

The US is the world’s largest user of nuclear power. Its 94 reactors supply nearly 19% of the country’s electricity. But the number of U.S. reactors has steadily fallen over the past 30 years and new nuclear power plants are a real rarity. The reasons are a combination of perceived dangers following several nuclear accidents and the increasing costs associated with building plants that can meet a growing number of regulatory requirements.

There are recent developments associated with new advanced reactor technologies that may lead to a resurgence in the use of nuclear power. Bill Gates’ energy company TerraPower is developing nuclear reactors that use sodium instead of water for cooling. Such reactors operate at lower pressures and higher temperatures.

Meanwhile, Kairos Power, a California-based energy company, has entered into an agreement with Google to build multiple small modular nuclear reactors that will supply electricity to that giant tech company. The modular reactors use a molten-salt cooling system combined with a ceramic, pebble-type fuel in order to transport heat to a steam turbine to generate power. The novel design of these reactors can reduce construction timelines, allow deployment in more places, and make final project delivery more predictable.

Surveys indicate that a majority of Americans favor the use of nuclear power, which has the advantages that it doesn’t create greenhouse gas emissions and can run 24-7. But traditional nuclear power plants are too expensive and have too many potential problems. These new nuclear power technologies may be the answer for allowing nuclear power to play an important role in the future energy system.

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New nuclear clean energy agreement with Kairos Power

Photo, posted May 16, 2016, courtesy of Steve Jurvetson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Importance Of Wildlife Crossings | Earth Wise

September 23, 2022 By EarthWise Leave a Comment

Highway accidents involving animals are a big problem for both people and animals. According to the National Highway Traffic Safety Administration, motorists in the United States kill one to two million large animals every year. About 200 people are killed annually in the U.S. as a result of those collisions with animals.

These crashes are expensive, too. Deer-vehicle collisions cost an average of more than $8,000 each; elk-vehicle collisions cost about $25,000; and moose-vehicle collisions cost more than $44,000.

One solution that has been quite effective around the world in reducing car-animal collisions is wildlife overpasses and underpasses. They are designed to help animals move in search of food and to escape predators and wildfires. These traffic-spanning bridges and tunnels have been popular in Europe since the 1950s. They look much like regular overpasses for cars but are decked out with native flora. The underpasses, which assist shyer and smaller animals, are typically invisible to drivers.

According to a new economic analysis by researchers at Washington State University, wildlife crossings in Washington State save roughly $235,000 to $443,000 every year per structure.

Wildlife crossing structures range in cost from $500,000 for a tunnel-like underpass to more than $6 million for a broad bridge. There may soon be many more wildlife crossing structures across the country since $350 million was allotted in the federal Infrastructure Investment and Jobs Act signed into law in 2021.

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Wildlife crossings potentially save millions annually in Washington state

How wildlife bridges over highways make animals—and people—safer

Photo, posted March 24, 2017, courtesy of Jeffrey Beall via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A New Kind Of Coral Nursery

October 22, 2019 By EarthWise Leave a Comment

Coral reefs around the world are struggling from warming waters and increasing ocean acidification driven by excess carbon dioxide. Many of the world’s greatest reefs – such as Australia’s Great Barrier Reef – have seen steep declines over the past decade.

But apart from the global environmental threat, reefs also are often damaged by various marine accidents such as ships grounding on them. Such events can severely damage a reef and scatter countless small coral fragments onto the seafloor. These small pieces of coral are not actually dead; they can continue on with their lives if they are relocated to a suitable environment such as a coral nursery.

Coral nurseries are generally small installations that allow coral fragments – typically pieces about 4 inches in length – to recover from their reef breaking up and to grow until they are large enough for conservation managers to replant them into reefs that need them. This strategy works well in places where corals grow relatively quickly – such as Florida and the Caribbean – but not as well in places where coral grows more slowly, such as Hawaii.

Recently, coral experts at the National Oceanic and Atmospheric Administration working with mechanical engineering students at the University of Hawaii have developed a new type of coral nursery that can save fully formed coral colonies as opposed to small coral fragments.

The nurseries are large, carefully designed structures that can be loaded up with corals that have become detached from their reefs. Some of these new structures were installed in the waters of Oahu in the summer of 2018 and were populated with corals. The relocated corals, which would have otherwise died, are now recovering nicely in their new coral daycare centers and will soon be replanted back into the reef.

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NOAA Develops A New Type of Coral Nursery

Photo, posted July 29, 2010, courtesy of Kyle Taylor via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Weather-Responsive Traffic Signals

April 17, 2019 By EarthWise Leave a Comment

We all spend time sitting at red lights – sometimes it seems like a whole lot of time. There is a fair amount of science applied in the design of traffic signals that at least has the aim of easing congestion and improving traffic safety.

Signals in modern cities are timed using optimization models that analyze multiple factors including traffic volume and speed with the goal of safely getting as many vehicles as possible through intersections. It sure doesn’t seem that way in many places, but that is the intent in any case.

But a real problem with these models is that they assume normal conditions including weather conditions. In places that experience real winter conditions, the assumptions of traffic models fail. If the road surface is covered with snow and ice and visibility is poor, variables like speed and stopping distances become very different.

Researchers at the University of Waterloo in Canada collected data from real-world intersections and ran computer simulations to determine the effects of adjusting traffic signal behavior in bad weather (as well as in the presence of other conditions such as accidents or construction.) They found that such adjustments could reduce traffic delays by as much as 20%.

Cities with computerized signal systems are already equipped to remotely and inexpensively adjust the timing of traffic lights. To gain the benefits of smarter signals, there would need to be video cameras and a certain amount of artificial intelligence software that would be able to automatically tweak the timing of lights in response to traffic changes caused by weather, accidents or construction.

It sounds like a great idea.

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Weather-responsive intersections could ease traffic congestion

Photo, posted September 22, 2009, courtesy of Tristan Bowersox via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Self-Driving Cars Safer

March 6, 2018 By EarthWise 1 Comment

We hear quite a bit about self-driving cars these days. More and more cars on the road have at least some ability to do things on their own (steer, brake, or park) and some can do much more.

Being Ready For Adverse Weather

December 25, 2017 By EarthWise Leave a Comment

Severe weather is a major cause of death and destruction. Recent hurricanes provided all too many examples. The catastrophic flooding from Hurricane Harvey led to more than 60 deaths and necessitated thousands of emergency rescues. And yet, increasingly, weather events like hurricanes don’t occur without warning and accurate weather forecasts are increasingly common.