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Storing carbon underground and abandoned wells

April 18, 2024 By EarthWise Leave a Comment

Using government support in the form of subsidies and tax credits, energy companies and others are planning to capture millions of tons of industrial carbon dioxide emissions and pipe the greenhouse gas into underground storage. It is a strategy enthusiastically supported by the fossil fuel industry because it allows them to keep burning the stuff.

There are currently 69 projects being reviewed by federal and state regulators seeking to store CO2 underground. The sorts of places where carbon dioxide can be injected are geologic zones containing porous rock formations which, in no way coincidentally, are the same places where oil and gas deposits are found. As a result, these places are studded with abandoned wells that have accumulated over the past century.

In Louisiana, there are about 120,000 abandoned wells that overlie geological zones that could store carbon dioxide. Environmental watchdog groups have identified numerous abandoned wells within a few miles of proposed storage sites.

The problem is that abandoned wells leak – even ones that have been plugged – and many haven’t been. The question is how much leakage will occur and what will be the consequences of the leakage. In Texas, pumping oilfield wastewater into abandoned wells has led to geysers of toxic water, artificial saline lakes, and earthquakes.

Underground carbon dioxide sequestering on a scale large enough to really matter will have to extend to very large areas. For example, injecting 100 million tons per year could create a pressurized zone as large as 100 miles. How large a problem this might create from abandoned wells in the zone is not at all clear but cannot be ignored.

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Companies Are Poised to Inject Millions of Tons of Carbon Underground. Will It Stay Put?

Photo, posted December 3, 2023, courtesy of Jason Woodhead via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Canadian zombie fires

April 8, 2024 By EarthWise Leave a Comment

Canada’s 2023 wildfire season was the most destructive ever recorded. Over 6,000 fires burned nearly 71,000 square miles of land from the West Coast to the Atlantic provinces. The burned areas are roughly the size of the entire country of Finland and represent almost triple the amount burned in the previous year, which itself was a lot. Smoke from Canadian fires, particularly those in Quebec, blanketed many cities in the United States and made its way as far south as Florida.

An alarming aspect of the Canadian fire season is that it didn’t ever really end. Late in the winter, 149 active wildfires are still burning across Canada. 92 are in British Columbia, 56 in Alberta, and one in New Brunswick. In these places, the wildfire season is yearlong.

These overwintering fires have come to be known as zombie fires. They burn slowly below the surface during the winter. Many areas in the north contain porous peat and moss ground cover and these act as underground fuel for smoldering fires.

Wildfires have become more prevalent in Canada because the changing climate has brought about increases in the hot, dry, and gusty conditions that lead to drought.

Many of the zombie fires don’t pose an increased threat of triggering wildfires in the spring because they are in places that are already so charred that there is nothing left to burn. But others are in drought areas that are basically tinder boxes ready to burst into flame once spring arrives.

Overall, Canadian government officials are warning that this year’s wildfire season is likely to be even worse than last year’s, particularly in the Western provinces of British Columbia and Alberta.

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As ‘Zombie Fires’ Smolder, Canada Braces for Another Season of Flames

Photo, posted June 30, 2023, courtesy of P. McCabe / EU via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Turning CO2 Into Rock

January 6, 2020 By EarthWise Leave a Comment

As the world continues to struggle to find ways to reduce carbon emissions, there is increasing attention being paid to so-called negative emission technologies (NET), which remove and permanently sequester carbon dioxide from the atmosphere.

The University of Victoria in British Columbia has brought together an international team of experts to explore the possibilities of permanently and safely sequestering CO2 as rock beneath the ocean floor. The Solid Carbon Project seeks to extract carbon dioxide directly from the air and then, using deep-ocean technology powered by offshore solar and wind energy, inject it into sub-seafloor basalt, where it would mineralize into solid carbonate rock.

When CO2 is injected into porous basalt, a type of volcanic rock, it reacts relatively quickly with minerals to form solid carbonate, thereby permanently removing it from the atmosphere. Because 90% of the planet’s basalt is located beneath the ocean floor, the deep ocean is the place to do this kind of carbon sequestration.

The team includes experts in ocean science, carbon mineralization, renewable energy, engineering design, and oil-and-gas drilling/injection operations. Other experts are focusing on the social and legal implications of the NET technology.

Over the next four years, the Solid Carbon Project will assess the integration of multiple existing technologies that will be needed to successfully develop this kind of carbon storage. One of these is the direct air capture technology itself, which will need to be adapted to a renewable energy-powered offshore platform. The best outcome technologies explored by the project will be selected for a real-world demonstration at Ocean Networks Canada’s observatory site, 9,000 feet underwater in the Cascadia Basin, off the coast of British Columbia.

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A rock-solid solution for CO2

Photo courtesy of the University of Victoria.

Earth Wise is a production of WAMC Northeast Public Radio.