leakage

More eco-friendly desalination

May 14, 2025 By EarthWise Leave a Comment

There are about 16,000 operational desalination plants, located across 177 countries, which generate an estimated 25 billion gallons of fresh water daily.

For every gallon of drinking water produced at a typical desalination plant, one and a half gallons of brine are produced. Much of it is stored in ponds until the water evaporates, leaving behind solid salt or concentrated brine for further treatment. There are various other techniques for concentrating brines, but they are energy-intensive and environmentally problematic. The process called electrodialysis uses electrified membranes to concentrate salts.

Water flows into many channels separated by membranes, each of which has the opposite electrical charge of its neighbors. Positive salt ions move towards negatively charged electrodes and negative ions move toward positive electrodes. Two streams result, one containing purified water and one containing concentrated brine.

This eliminates the need for evaporation ponds, but existing electrodialysis membranes either result in leakage of salts into the environment or are too slow, making the process impractical for large-scale use.

Researchers at the University of Michigan have developed a new kind of membrane for electrodialysis. The new membranes don’t leak and are ten times more conductive than those on the market today which means that they can move more salt using less power. The membranes can be customized to suit a broad range of water types, which may help make desalination a more sustainable solution to the world’s growing water crisis.

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Making desalination more eco-friendly: New membranes could help eliminate brine waste

Photo, posted February 4, 2012, courtesy of David Martinez Vicente via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Artificial intelligence and lost oil wells

January 2, 2025 By EarthWise Leave a Comment

There have been commercial oil and gas wells across the United States for 170 years. Researchers estimate that there are between two and three million wells that have been abandoned. There are hundreds of thousands of them, across 27 states, that are “orphaned,” meaning that they are uncapped, unproductive, and nobody is responsible to manage their leakage or pollution.

Many are undocumented orphaned wells – UOWs – that are not listed in formal records and are basically out of sight and out of mind. Besides having nobody responsible for them, nobody even knows where they are. But they are potential sources of oil and chemical leaks into nearby water sources and can send toxic substances like benzene and hydrogen sulfide into the air.

Researchers are using modern tools like drones, laser imaging, and advanced sensors to try to locate UOWs. But these wells are scattered over an area of more than three million square miles.

To better predict where to look for undocumented wells, researchers are combining historical topographic maps with artificial intelligence. The US Geological Survey has scanned 190,000 topographic maps made between 1884 and 2006. AI is being used to find the symbols for oil and gas wells on the maps. People can recognize these symbols easily, but there are just too many maps to look at. The problem is equivalent to finding a needle in a haystack; there is just an awful lot of hay to look through.

Abandoned wells are a big problem and it will take lots of modern technology to try to solve it.

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AI Helps Researchers Dig Through Old Maps to Find Lost Oil and Gas Wells

Photo, posted August 16, 2022, courtesy of Larry Syverson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The cost of methane emissions

April 26, 2024 By EarthWise Leave a Comment

Stanford University-led research has determined that American oil and gas operations are emitting more than 6 million tons of methane each year. The emissions come from both intentional vents and unintentional leaks.

Methane is the main component of natural gas and losing that much of it through leakage is costing the industry a billion dollars a year just in lost revenue. Adding in the harm to the economy and human well-being caused by adding this much potent greenhouse gas to the atmosphere is estimated to increase the cost of these emissions to $10 billion a year.

These emission and cost estimates are roughly three times the level predicted by the U.S. government. The Stanford numbers are based on roughly a million aerial measurements of wells, pipelines, storage, and transmission facilities in six of the nation’s most productive oil and gas regions located in Texas, New Mexico, California, Colorado, Pennsylvania, and Utah. These areas account for 52% of U.S. onshore oil production and 29% of gas production.

The survey also found that fewer than 2% of the methane emitters are responsible for 50-80% of emissions in four of the regions. It also found that midstream infrastructure – which includes gathering and transmission pipelines, compressor stations, and gas processing plants – is responsible for about half of total emissions.

While the federal government estimates that methane leakage averages about 1% of gas production, the new survey puts the number at 3%, and some regions lose almost 10% to leakage.

Better tracking and fixing these leaks – especially the larger ones – is essential for climate change mitigation.

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Methane emissions from U.S. oil and gas operations cost the nation $10 billion per year

Photo, posted June 5, 2015, courtesy of Dave Houseknecht / USGS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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

The Bengal Water Machine | Earth Wise

October 31, 2022 By EarthWise Leave a Comment

Over the past three decades, the owners of 16 million small farms in the Bengal Basin of Bangladesh have been pumping shallow groundwater during dry seasons to irrigate rice paddies. By lowering groundwater levels in this way during the dry season, the ability of leakage from rivers, lakes, and ponds to replenish the groundwater was greatly enhanced. Capturing surface water not only improved the recovery of groundwater levels but only helped to reduce flooding during monsoons.

The net result of this enormous collective groundwater pumping by millions of farmers has been the creation of vast natural reservoirs underground that are comparable to what is contained by many of the world’s largest dams. This system of sustaining irrigation has transformed what was previously a famine-prone country into a food-secure nation.

The details of this remarkable transformation have been laid out in a study by University College London recently published in the journal Science. According to the study, over the course of 30 years, more than 75 cubic kilometers of fresh water was captured by this process, which is equivalent to the combined reservoirs of China’s Three Gorges Dam and the Hoover Dam in the U.S.

The authors of the study described the water cycling process as “The Bengal Water Machine” and argue that it can be a sustainable alternative to conventional approaches to seasonal river flow storage for irrigation, which typically involve dams and reservoirs. Such approaches are difficult to implement in densely populated alluvial plains where sand, silt, and clay are laid down by annual floodwaters.

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Millions of farmers “replumb” world’s largest delta

Photo, posted February 2, 2010, courtesy of Melanie Ko via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Detecting Methane

December 23, 2019 By EarthWise Leave a Comment

Natural gas has become a huge industry in the United States, increasingly replacing coal in power plants, and otherwise contributing to energy independence. Unfortunately, it also contributes to climate change. Methane – the primary component of natural gas – is a powerful greenhouse gas that is estimated to be responsible for as much as a quarter of atmospheric warming.

Not all of the emissions from natural gas come from its use. In the United States, so-called fugitive emissions from the oil and gas industry total an estimated 13 million metric tons per year. These emissions basically consist of leakage of various types from the extraction, transportation, and processing of natural gas and cost the industry $2 billion in lost revenue each year. Globally, that figure is estimated to be $30 billion.

Research labs and startup companies are working on developing and deploying novel technologies to address the growing issue of methane leaks across the fossil fuel supply chain.

One company called LongPath Technologies – a spinout from the University of Colorado – uses frequency comb laser technology that can pinpoint a leak to about a 50 square-foot area from half a mile away. Other companies use different variations on laser absorption technology to be able to measure methane concentrations from a distance.

Methane is a much more powerful greenhouse gas than carbon dioxide, but it stays in the atmosphere for much less time. As a result, reducing methane emissions can pay off much more quickly than reducing carbon dioxide emissions.

The current EPA is trying to eliminate emissions regulations on the natural gas industry, but it is in the industry’s economic interest to curb those emissions even if they were unconcerned about the environment.

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