Tag Archives: Environment


Inside the World’s Largest Carbon-Capture Test Facility

9NWCarbonCaptureNorwayLucasLaursen-1380053153263In a laboratory on Norway’s fjord-laced coast, Jane Feste bubbles some carbon dioxide gas through a liquid for a crowd of visitors. “I will take an amine—that’s a base—and that will absorb…the CO2. So [that’s] what’s happening out in the plant, just shown for the eye here,” the laboratory technician explains. She’s referring to Technology Centre Mongstad (TCM), the US $1 billion, 350-megawatt power plant and test facility that the Norwegian government and several energy firms built. The assembled journalists cannot seem to decide if they should applaud the spectacle or if they’re witnessing a modern case of the emperor’s new clothes.

Under rules announced last week by the U.S. Environmental Protection Agency, future coal-fired power plants in the United States can emit no more than 500 kilograms of CO2 per megawatt-hour. That’s a level experts say can be achieved only by carbon capture and sequestration. Yet until last year, the biggest carbon-capture facilities, all pilot projects, had little more than 1 percent of the capacity required for commercial operations. Although it was launched behind schedule and over budget in May 2012, TCM is about 10 times as big as the largest pilots, and it is the best glimpse we have of the future of fossil-fuel electricity generation. The facility is intermediate in size, between pilot plant and commercial scale, offering companies a way to test how their equipment and processes will hold up in a commercial setting. “What we’d like to do is test here a little bit more high-risk, high-reward technologies,” explains TCM technology manager Olav Falk-Pedersen, who has been involved in the first year’s testing of postcombustion carbon capture.

The facility, which is adjacent to the town of Mongstad, hosts two types of carbon-capture technologies, with a gravel-filled lot available for a third. The test sites draw carbon emissions from two adjacent power plants: an oil refinery with a catalytic cracker and a natural-gas-burning combined heat and power plant. Those two sources allow TCM to simulate different kinds of real-world emissions, including those from coal power plants.

With carbon-emitting energy sources slated to remain an important part of the global energy mix for decades, and carbon-emissions reductions starting to find their way into government policies, the rewards for those making carbon capture cost-effective could be very high.

But capturing carbon sacrifices a lot of energy—up to 25 percent of that produced in a coal plant, says research engineer Howard Herzog, director of the Carbon Capture and Sequestration Technologies Program at MIT. It also uses more heat, water, and raw chemicals. The rewards will go to those companies that find the cheapest way to approach the thermodynamic limits of carbon capture, which Herzog says is closer to an 8 percent energy loss for a coal-fired power plant.

So far, the two methods being tested at Mongstad show that one day there may be several carbon-capture solutions, each tailored to a different environment. In a 60-meter-tall concrete tower, a liquid amine solution drips down metal baffles, absorbing CO2 from flue gas via the amine method that Feste demonstrated to the visiting journalists. The amine solution can then be stripped of its carbon dioxide and recycled. This method is currently being tried out by Aker, an oil-services company. Next door, a boxier tower bristling with pipes and yellow safety railings tests the rarer chilled-ammonia method, which energy company Alstom is developing. The two systems have similar energy needs but require distinct balances of steam, electricity, and cooling water. Ammonia captures carbon at a lower temperature than amine does.

While the tests of the two technologies have been proceeding simultaneously, Falk-Pedersen says they are not really competing with each other. Instead, builders of future facilities will decide which method to use based on local availability and prices for heat, electricity, water, and solvents such as amine or ammonia. Sun-soaked Dubai, for example, may prefer a different method to hydropowered Norway.

“I’m very interested to see what data come out of those tests and what’s their plan for future tests,” says Herzog, who maintains a global database of carbon-capture and sequestration projects. That data will help industry watchers decide which proprietary amine mixes and capture processes have best survived the transition from computer simulation to real-world system. Builders will also need to choose among the companies that make carbon-capture equipment, such as Alstom and Aker.

To scale up pilot technology from a typical 10 000 metric tons of CO2 per year to the capabilities of TCM, which can capture up to 100 000 metric tons of CO2 per year, some of the reengineering will be straightforward. It will involve building larger pipes to carry more power-plant exhaust to the test flues and ensuring consistent flow inside the larger test flues. Other, more subtle changes will involve fine-tuning the mix of additives in the amine to minimize corrosion and degradation of the equipment.

But there’s no point in making those changes without measuring their results. At one stop on the tour of the valve- and gauge-filled facility, Falk-Pedersen notes that no commercial facility would pay to install so many instruments in the pipes carrying gas and liquid through the complex. Here, there are 4000, feeding data in real time to TCM and its partners.

Norway’s new government announced last week that it would not escalate the Mongstad site to commercial-scale operation. The decision came just after an audit accused Statoil of poor financial management of the project. However, the government will boost TCM’s R&D budget, and it still plans to build a commercial-scale CCS facility somewhere in the country. So far, the country has been willing to go it alone on scaling up carbon-capture technology—many other countries have canceled demonstration projects amid the recession and austerity drives. TCM’s managing director, Frank Ellingsen, says, “It’s obvious today that [carbon-capture] technology is not a very viable industry” without government support.

However, the largest energy firms are betting that carbon capture and sequestration will someday be a viable business—almost a dozen approached TCM about securing a spot in the next round of equipment testing. They’re just letting governments take the lead on the investment.

By the time coal-power generators start making those investments for real, TCM might be pumping its captured carbon into the subsea salt deposits just beyond the ships docked at the edge of Mongstad’s refinery. But for now, it’s all catch and release.

First published by IEEE Spectrum: [html] [pdf]


Spain’s Lead-Lined Lakes

ja13-coverResearchers from the University of Granada collected mountain lake sediments from Laguna de Río Seco in southern Spain that had accumulated over 10,000 years, trapping deposits from the atmosphere. In these stacks of mud, they found fine layers of lead that reveal millennia of metalworking and migration, and may be the oldest evidence of air pollution in southern Europe. “[The mud] has been capturing the evolution of air pollution from the Neolithic to present times and giving us an idea of the activity of each of the populations that have passed through southern Iberia,” says team leader José Antonio Lozano, “such as the Phoenicians, Romans, Visigoths, Moors, and more.”

The team dates the first man-made uptick in pollution to between 3,900 and 3,500 years ago, which matches the appearance at nearby sites of coins, weapons, and decorations that, when made, left behind lead by-products. The lead records also attest to a quiet period, when mining moved elsewhere in Iberia, and to a spike corresponding with a period of Roman mining. But all those signals are dwarfed by a more modern surge, which the team attributes to the leaded gasoline in heavy use from the 1950s to the 1970s. The good news, the researchers report, is that present-day lead levels are already below those of the worst Roman deposits.

This From the Trenches item first appeared in the July/August 2013 issue of Archaeology Magazine: [html] [pdf]

New Agreement Casts Spotlight on Efforts to Inventory Black Carbon

Researchers are about to take a big step toward better understanding a tiny air pollutant. A U.N. expert panel earlier this month agreed on a technical road map that will guide the first multinational effort to create a standardized emissions inventory of black carbon, a kind of microscopic soot particle. Scientists say that black carbon emissions play an important but poorly understood role in both global climate change and air pollution.

“The increased emphasis on complete reporting across the countries … is clearly an important step forward,” says atmospheric scientist Chris Dore, chair of the U.N. task force, which helps implement the 1979 Geneva Convention on Long-range Transboundary Air Pollution. Fifty-one nations, including the United States and members of the European Union, abide by the convention.

The move reflects growing concern about black carbon particles, which are produced by burning an array of fuels, including oil, wood, crop residues, and even garbage. Health researchers consider airborne soot particles smaller than 2.5 micrometers a major health threat, causing lung disease and premature death. And climate scientists say that black carbon is a key player in global warming because it can absorb solar radiation and accelerate ice melting.

Efforts to calculate black carbon’s full impact, however, suffer from incomplete emissions data. A January study in the Journal of Geophysical Research: Atmospheres, for instance, concluded that existing climate models underestimate black carbon’s climate-changing contribution by up to a factor of three as a result of data gaps in key regions. Existing inventories, such as those created by measuring emissions from smokestacks and tailpipes, contain large uncertainties, says atmospheric physicist Philip Stier of the University of Oxford in the United Kingdom. In part, that’s because they are often designed to show only that a nation is complying with air pollution rules and don’t include soot sources such as forest and cooking fires, or particles that settle on roadways and are lofted into the air by passing cars. “Black carbon is a poorly defined substance,” Stier says. “It’s always measured in a slightly different way, [which] doesn’t always refer to the same material.”

The new road map—unveiled on 20 May after a meeting of the United Nations Economic Commission for Europe’s Task Force on Emission Inventories and Projections in Istanbul, Turkey—aims to put nations on the same page. The voluntary plan calls for nations to start measuring black carbon emissions from an array of sources, including transportation, the energy industry, and agriculture. Nations will add the data to annual emissions reports and dig into existing data to calculate past emissions going back to the year 2000. The plan also requests emissions projections out to 2050.

Dore expects a U.N. steering body to approve the plan later this year, and nations will begin reporting in 2015, although a few could start in 2014. Some nations may go beyond the guidelines to collect additional data, including measures of black carbon sources not covered by the road map. The voluntary guidelines could one day become mandatory, following a path taken by other pollutants covered by the convention.

The inclusion of black carbon emissions in the annual reports is “really important,” says aerosol scientist Catherine Liousse of the Midi-Pyrenees Observatory in Toulouse, France. It will encourage nations that now don’t measure such emissions to start and enable better comparisons of existing inventories by promoting standard methods.

Researchers, meanwhile, are working to develop better methods for getting a broader picture of black carbon in the atmosphere. One $3 million study sent a Gulfstream jet with air-sampling instruments on undulating flights—from 150 meters to 13,500 meters—in five study areas around the world over several years. Other researchers are mounting low-cost black carbon detectors on ultralight aircraft and drones. Their goal is to better understand the role black carbon is playing in different parts of the atmosphere: While climate researchers may care more about soot interactions with frozen water droplets, for instance, health researchers want to compare how different-sized particles affect the lungs.

First published by Science Magazine [html] [pdf]

Spain replants after centuries of deforestation

Around this time of year in the Sierra de Guadarrama, a snow-capped mountain range outside Madrid, the snow is starting to melt. Below the tree line, the melting water soaks the earth in dense stands of pine trees. Further down, holly, oak and ash trees line the banks of mountain streams, and goats graze between granite rock formations.

Rubén Bernal, a guide at Guadarrama National Park, knows his trees. Walking down the mountain, he points out junipers, oaks, alders, honeysuckles, blackthorns, wild privets, butcher’s brooms – and the wild apple, which he said is the most protected. “Buckthorn, madrone – everything near the water,” Bernal said.

Bernal explained that the forests here were burned to make charcoal, or to clear land for sheep to graze – once common practices throughout Spain. When the government first took stock of the damage in the late 19th century, it estimated that 5 or 6 million hectares – or about 10 percent of the country’s land area – would need to be replanted.

The reforestation work continues to this day.

Hear the full radio report and see the online story at DW [html] [mp3]