falling

Lower carbon emissions in the U.S.

February 7, 2024 By EarthWise Leave a Comment

American greenhouse gas emissions in 2023 fell by 1.9%. In total, U.S. emissions have now fallen by over 17% since 2005. The largest factor in the decline has been the reduction in the burning of coal to produce electricity. Coal-fired generation has fallen to its lowest level in half a century.

There was a huge drop in emissions at the start of the covid pandemic when large segments of the economy shut down. But then there was a sharp rebound in emissions in the following two years when economic activity resumed. But over the long term, American emissions have been trending downward as both cars and power plants have become cleaner and greener.

The decline in emissions is a good thing but hasn’t been nearly enough to meet the nation’s goals for trying to slow down global warming. The U.S. has a goal of reducing emissions by 2030 to half of the 2005 level. To achieve that goal, annual emissions would have to fall more than three times faster than they did last year for the rest of the decade.

The emissions data used for the current assessment included those from transportation, electricity generation, industry, and buildings. It did not include pollution from agriculture, which accounts for about 10% of the nation’s greenhouse gases.

The 2022 Inflation Reduction Act provided record amounts of money for low-emissions technologies like solar panels, wind turbines, nuclear reactors, electric vehicles, and hydrogen fuels. The full impact of these federal investments has yet to be seen, since many companies are still ramping up their efforts in clean energy. How quickly emissions will fall as these efforts come to fruition remains to be seen.

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U.S. Carbon Emissions Fell in 2023 as Coal Use Tumbled to New Lows

Photo, posted May 17, 2020, courtesy of Frans Berkelaar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Falling Lithium Prices | Earth Wise

May 1, 2023 By EarthWise Leave a Comment

Lithium, the key element in the batteries that power electric cars, as well as smartphones, tablets, and laptop computers, is sometimes called white gold. Over time, the price of the metal has gone up and up. But recently, and surprisingly, the price of lithium has actually gone down, helping to make electric vehicles more affordable.

Over the first couple of months of this year, the price of lithium has dropped by nearly 20%. The price of cobalt, another important component of vehicle batteries, has fallen by more than half. Even copper, another battery material, has seen its price drop by 18%.

Many analysts predicted that prices of these commodities would stay high or even climb higher. The reason for the decline, as well as whether it is likely to persist, is the subject of much debate.

Some experts believe that the price drops are a result of demand not being as high as expected, perhaps related to slowing sales growth of EVs in Europe and China after certain subsidies expired. Other industry experts said that the drop was a result of new mines and processing plants providing additional supply sooner than was thought possible.

Despite the price drops, mining and processing lithium remains an extraordinarily profitable business. It costs from $5,000 to $8,000 to produce a ton of lithium that sells for ten times that amount. With such fat profit margins, there is no shortage of banks and investors eager to finance lithium mining and processing projects. Such profit margins are probably not sustainable and that will likely result in more reasonable prices over time.

There is plenty of lithium in the world. The huge demand for it is a recent phenomenon and the world is still working out how to meet that demand.

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Falling Lithium Prices Are Making Electric Cars More Affordable

Photo, posted January 9, 2023, courtesy of Phillip Pessar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Polar Bears and Tires | Earth Wise

January 12, 2023 By EarthWise Leave a Comment

There is lots of interest in traction. People want to find better ways to move across wet and frozen surfaces safely. This applies to both the shoes on our feet and the tires on our cars.

Researchers at the University of Akron along with colleagues at Syracuse University and at Bridgestone, the tire company, have been studying how many arctic animals can walk and run across the ice without slipping and falling. Their research focused on the paws of polar bears.

Previous studies discovered that polar bears have papillae – little bumps on the pads of their feet – that provide improved traction on snow. The new research also looked at the paws of other species of bear – brown bears and black bears – and found that these others also have papillae on their paw pads, but that those of polar bears are as much as 50% taller. These taller bumps give the pads a 30-50% increase in frictional shear stress.

The research may lead to various applications. For example, snow tires typically have deeper treads, but the polar bear study may lead to some new designs that would improve traction. People who do high-altitude climbing are interested in the research as are companies that deliver goods in bad weather. Anyone who has to be out and about in bad weather would like to get a better grip.

There are various other animals with traction-improving adaptations that are probably worth studying. These include dogs, wolves, foxes, and mountain goats. The same researchers at Akron have also studied other animals with unique abilities to deal with challenging surfaces including geckos, spiders, and mussels. The natural world is filled with examples of creatures who can easily function in environments that we humans find very challenging.

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UA researchers’ focus on tire traction leads to investigation of polar bear paws

Photo, posted March 2, 2008, courtesy of Sam Weng via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Falling U.S. Carbon Emissions

September 16, 2019 By EarthWise Leave a Comment

Reducing carbon emissions is a goal embraced by nearly every country in the world, but actually accomplishing it isn’t easy. It is true that renewable energy sources are playing a growing role in energy systems, but counterbalancing that trend is growing energy demand, especially in developing countries.

Here in the US, energy-related CO2 emissions actually went up nearly 3% in 2018 compared with 2017. But the US Energy Information Administration is now forecasting a 2% drop in emissions this year.

The main reason energy-related emissions are headed lower at this point is coal-fired power plant retirements. More than 90% of the coal used in the US goes toward electric power and utilities are increasingly turning away from coal.

The rapid shift away from coal has mostly been due to the increasing use of natural gas. Natural gas is not actually a clean and green fuel, but it is definitely less carbon-intensive than coal. Overall, the total installed capacity of renewable sources – hydropower, wind, solar, geothermal, and biomass – has now actually surpassed the capacity of coal plants. Given that renewables have in many places become the cheapest power option, there is little chance that coal has much of a future, despite efforts by the current administration.

The electric power sector is gradually moving away from all carbon-emitting sources – a trend that is being reinforced by legislation in many states. The real CO2 emissions leader is petroleum, which accounts for nearly half of the total. We have a long way to go to reduce emissions from the use of petroleum. There are over 250 million cars and trucks on US roads and only a little over a million of them don’t burn fossil fuels.

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Photo, posted November 6, 2017, courtesy of Cindy Shebley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.