decarbonizing

Capturing hot carbon dioxide

December 13, 2024 By EarthWise Leave a Comment

Decarbonizing industries like steel and cement is a difficult challenge. Both involve emitting large amounts of carbon dioxide both from burning fossil fuels and from intrinsic chemical reactions taking place. A potential solution is to capture the carbon dioxide emissions and either use them or store them away. But this sort of carbon capture is not easy and can be quite expensive.

The most common method for capturing carbon dioxide emissions from industrial plants uses chemicals called liquid amines which absorb the gas. But the chemical reaction by which this occurs only works well at temperatures between 100 and 140 degrees Fahrenheit. Cement manufacturing and steelmaking plants produce exhaust that exceeds 400 degrees and other industrial processes produce exhaust as hot as 930 degrees.

Costly infrastructure is necessary to cool down these exhaust streams so that amine-based carbon capture technology can work.

Chemists at the University of California, Berkeley, have developed a porous material – a type of metal-organic framework – that can act like a sponge to capture CO2 at temperatures close to those of many industrial exhaust streams. The molecular metal hydride structures have demonstrated rapid, reversible, high-capacity capture of carbon dioxide that can be accomplished at high temperatures.

Removing carbon dioxide from industrial and power plant emissions is a key strategy for reducing greenhouse gases that are warming the Earth and altering the global climate. The captured CO2 can be used to produce value-added chemicals or can be stored underground or chemically-reacted into stable substances.

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Breakthrough in capturing ‘hot’ CO2 from industrial exhaust

Photo, posted March 3, 2010, courtesy of Eli Duke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Industrial heat and solar power

July 2, 2024 By EarthWise Leave a Comment

Many industrial processes require extremely high temperatures, typically more than 1,800 degrees Fahrenheit. This heat is generally produced by burning fossil fuels – either coal or natural gas – which emits large amounts of greenhouse gases. This level of heat cannot be economically produced using renewable electricity. As a consequence, decarbonizing these industrial processes is very difficult.

Researchers at ETH Zurich in Switzerland have recently demonstrated a new method of obtaining high-temperature heat based on solar radiation. They have engineered a device called a thermal trap. It consists of a quartz rod coupled to a ceramic absorber that can efficiently absorb sunlight and convert it to heat.

In laboratory-scale experiments, they exposed a foot-long quartz rod to artificial light 135 times more intensive than sunlight and were able to produce temperatures as high as 1,900 degrees. The artificial light source was needed to mimic the effects of concentrated solar energy plants that typically make use of large numbers of mirrors to direct intense solar energy onto a small area.

There are already concentrated solar power plants that operate at temperatures as high as 1,100 degrees and use the heat to operate turbines to generate electricity. These plants lose efficiency at higher temperatures because of radiative heat losses. The Zurich thermal trap minimizes these losses and permits higher temperature operation.

The hope is that at a large scale, the new approach may make it possible to use solar energy to decarbonize energy-intensive industrial processes.

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Using solar energy to generate heat at high temperatures

Photo courtesy of ETH Zurich / Emiliano Casati.

Earth Wise is a production of WAMC Northeast Public Radio

Decarbonizing Could Save Trillions | Earth Wise

October 18, 2022 By EarthWise Leave a Comment

Scientists have long been calling for a transition to clean energy to prevent catastrophic impacts of climate change. For much of that time, many people and, specifically, many of those in power, were skeptical of the need to do something about the warming climate. But even as the facts about the changing climate became increasingly undeniable, there continued to be fears that the transition to clean energy sources would be unacceptably expensive and harmful to the economy.

A recent study published by Oxford University shows that the opposite is true: a concerted effort to convert to green energy technologies such as solar, wind, and batteries, will save the world enormous amounts of money.

The Oxford study shows that a transition to nearly 100% clean energy by 2050 results in a lower-cost energy system that provides energy access to more people around the world. The energy transition is expected to save the world at least $12 trillion compared to continuing our current levels of fossil fuel use.

The cost of renewable energy sources has been going down for decades and they are already cheaper than fossil fuels in many situations. It is expected that they will become cheaper than fossil fuels across almost all applications over time. Accelerating the transition will allow renewables to become cheaper faster.

The study made use of probabilistic models to estimate the costs of various possible future energy systems based on past data. Even the most pessimistic models showed that scaling up green technologies is likely to drive their costs down so far that they will generate net cost savings and that the faster the transition goes, the more will be saved. The result will be a cleaner, cheaper, more energy secure future.

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Decarbonising the energy system by 2050 could save trillions

Photo, posted July 12, 2010, courtesy of Tom Shockey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Primary Ways To Mitigate Climate Change | Earth Wise

May 30, 2022 By EarthWise Leave a Comment

The most recent report issued by the Intergovernmental Panel on Climate Change states that the world must halt the increase in greenhouse gases within three years, reduce emissions by 43% in the next seven years, and eliminate them entirely by 2050. Otherwise, there will likely be catastrophic and irreversible impacts on the climate.

With respect to achieving these reductions, the report emphasizes decarbonizing the energy sector through electrification by replacing fossil fuels anywhere and everywhere possible. Where that isn’t yet practical – such as in shipping and aviation – the use of biofuels and hydrogen can provide a stopgap until battery technology becomes a viable alternative.

The economics of this approach continue to improve. Since 2010, the cost of wind, solar, and batteries has declined by as much as 85%. In many cases, costs have fallen below those of fossil fuels. Nonetheless, the report stresses that continuing to provide national, state, and local incentives for using renewable energy is a key factor in achieving the necessary reductions.

However, reducing emissions will no longer be enough. This is the first major IPCC report that states that man-made carbon dioxide removal strategies will be necessary to meet the goals of the Paris Climate Agreement. So-called natural carbon storage options, like planting trees and using farming methods that sequester carbon in soil, are also important parts of the strategy.

It is up to governments, policymakers, and investors to implement the necessary changes to mitigate climate change. There is lots of talk about it, but it will take concerted action to avoid increasingly dire consequences.

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Report highlights affordable, available ways to mitigate climate change now

Photo, posted September 8, 2007, courtesy of Kevin Dooley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Tough Day For Big Oil | Earth Wise

June 24, 2021 By EarthWise Leave a Comment

May 26th was a difficult day for big oil. Three major setbacks for the industry occurred on the same day.

A Dutch court ruled in a case against Shell, ordering the company to cut emissions by 2030 in accordance with the goals of the Paris Climate Agreement. The case was brought by climate activists, ultimately comprising 17,000 co-plaintiffs. The ruling will probably be appealed but it does represent a major precedent for holding polluters accountable for their actions.

That same day, shareholders of ExxonMobil replaced at least two of the company’s board members with candidates dedicated to decarbonizing the company. Having two board seats filled by climate supporters is not likely to radically transform the company, but it is a powerful rebuke of Exxon’s iconic business model of “drill, baby, drill”.

Finally, Chevron’s shareholder meeting on May 26th saw 61% of shareholders voting for the company to reduce its so-called Scope 3 emissions, meaning the pollution from all the fossil fuels it sells. In addition, 48% of shareholders voted to demand a report on Chevron’s dark money lobbying. That initiative did not carry, but nevertheless, nearly half of the company’s shareholders expressed concern about how Chevron is corrupting the political process in order to achieve its ends.

These events are examples of mainstream activism where the pressure on fossil fuel companies is not just coming from the usual environmental activists but rather from shareholders, who after all actually own the companies. The fossil fuel industry still wields enormous power, but it appears increasingly possible to challenge it and even to win.

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A landmark day in the fight against fossil fuels

Photo, posted August 15, 2014, courtesy of Mike Mozart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Scottish Wind Power

September 5, 2019 By EarthWise Leave a Comment

Scotland is a windy country. Most wind turbines in the European Union produce electricity at an average of 25% of their maximum rated power as a result of the variability of wind resources. The west and northern coasts of Scotland have an average capacity of 31% or more. Some wind farms in Scotland have achieved more than 50% capacity over the course of a year.

As of the end of last year, Scotland had more than 8 GW of installed wind power capacity. This included 7.8 GW of onshore wind and 623 MW of offshore wind generators. Estimates are that more than 11 GW of onshore wind could be installed in Scotland. The total offshore potential is far greater than that but would be much more expensive. There are multiple large-scale wind farms proposed or under construction in Scotland.

All of this growth in wind power has led to some remarkable results. During the first half of 2019, wind turbines in Scotland produced enough electricity to power every home in the country twice over. Scottish wind farms generated nearly 10 million megawatt-hours between January and June, which is equal to the consumption of 4.5 million homes during that period. That is enough to take care of all of Scotland’s homes plus a large portion of northern England’s.

Scotland has set a target of generating half of its electricity from renewable sources by 2030 and decarbonizing its energy system almost entirely by 2050. The recent performance of its wind power installations shows that the country might be able to reach its goal much sooner than anticipated.

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Scotland’s Wind Farms Generate Enough Electricity to Power Nearly 4.5 Million Homes

Photo, posted March 27, 2017, courtesy of Ian Dick via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.