ALASKA RESOURCE REVIEW SUMMER 2024 38 Carbon capture would result in ‘net-zero’ of carbon release BY TIM BRADNER NEW RESEARCH BY THE UNIVERSITY OF ALASKA FAIRBANKS SHOWS CLEAN ALASKA COAL AND CARBON CAPTURE PROJECTS ARE PERFECT PARTNERS. Working with U.S. Department of Energy support, the university study now shows that an Alaska coal-burning power plant with CO2 emissions largely removed with carbon capture systems, and with the gas permanently stored underground, can approach “net-zero” in carbon release. The cost of power generated, including the coal cost and the cost capturing and storing CO2 underground, appears highly competitive with energy sources like imported liquefied natural gas and even conventional natural gas combined with renewable energy from wind or solar, according to the UAF research. Federal clean-energy tax credits are important in this calculation. Critics will argue that the tax credits may be temporary, which could undermine the long-term economics. But many wind and solar projects are helped by the federal tax credits, too, so the same argument applies. Carbon capture is a hot research topic today. The University of Alaska Fairbanks and a team of partners was selected by the U.S. DOE to lead a study of whether the process could work in Alaska. What’s important is that CO2 capture from a coal plant relies on proven technology. The basic process has been used for years in many industries. It works well with coal because the CO2 is more concentrated in coal emissions than in emissions from a gas-fired plant, for example, where the technology is less developed and more challenging. That’s because the carbon dioxide is less concentrated in the emissions from a natural gas plant. There’s also a lot of research and development under way on capturing CO2 directly from the air, but this is still in the initial stages of development. For purposes of its research, the university used a plausible, but still hypothetical 400-Megawatt power plant and a coal mine near Skwentna in the western Matanuska-Susitna Borough. The study assumed a new 75-mile pipeline would be built to carry the captured CO2 to the existing Beluga gas field west of Anchorage. The Beluga field has a lot of underground reservoir space available for CO2 storage, estimated to be sufficient for more than 60 years of carbon dioxide storage. The example also assumes a 75-mile power transmission line to Chugach Electric Association’s Beluga power station near the gas field. From there the new coal-fired power could be connected with Chugach’s existing transmission, feeding it into the “Railbelt” electric grid that serves Southcentral Alaska. Skwentna was used as an example because there are known coal resources. And Flatlands Energy is now exploring for more. There is a market for the power in Southcentral Alaska if the coal plant and transmission line were built. The predicted shortfall of natural gas from Cook Inlet gas fields has utilities in the region searching for alternative sources of energy. A large power plant and coal mine at Skwentna, which is in a remote area, has its challenges. But power plants and transmission lines have been built before in less-accessible areas and without road ALASKA CLEAN COAL KEY TO NET-ZERO SOLUTION Here’s data from the university’s study on carbon dioxide emissions, in metric tonnes of CO2 per gigawatt hour of electricity: Coal without carbon capture: 1,100 tonnes Natural gas, current: 550 tonnes Wind power with natural gas backup*: 250 tonnes Coal with carbon capture: 100 tonnes * A wind or solar project must have backup power for reliability. Note: A metric tonne is 2,200 pounds compared with a U.S. ton, at 2,000 pounds Here are cost estimates used in UAF’s study: n Capital cost of power plant with carbon capture facilities: $3.6 billion n Cost of carbon dioxide pipeline to Beluga gas field: $150 million n Coal-fired power without carbon capture: $99 per Megawatt hour n Coal-fired power with carbon capture: $75 per Megawatt hour n Natural gas-fired power (assumes higher cost LNG import): $307 per Megawatt hour
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