by Bob Shively, Enerdynamics President and Lead Instructor

A key promise of Trump’s presidential campaign was revitalization of the coal industry to maintain coal-related jobs in the U.S. But as we pointed out in our Energy Insider article  “The Election Is Over: What’s In Store for the Energy Industry Under the Next Administration?”, it is unlikely that administration policies will do much to help a coal industry reeling from low natural gas prices combined with local and international energy policies designed to reduce greenhouse gas (GHG) emissions.

Indeed, since the inauguration, U.S. utilities have announced planned closures of the largest coal unit in the West and two large coal units in the Midwest[1]. And China, with its current fleet of more than 50% of the world’s coal capacity and more under construction, seems to be serious about reducing coal emissions[2].

But perhaps for the longer term, the coal industry saw a hint of light at the beginning of 2017 with the completion of the Petra Nova carbon capture plant southwest of Houston, Texas. Unlike other recent carbon capture generation units, the Petra Nova plant was completed essentially on time and on budget. The unit will capture 90% of the carbon dioxide (CO2, which is a key GHG) emitted from 240 MW of generation and will then pump the carbon through a pipeline for injection into a nearby oil field. The injection of the carbon will help producers capture more oil by stimulating flows, and the producers will pay Petra Nova for the CO2, thus creating a revenue stream for the power plant owners.

What is carbon capture and storage?

Carbon capture and storage (CCS) is the process of removing carbon from a fossil fuel stream, either pre- or post-combustion, and then storing the carbon in a location where it cannot leak into the atmosphere. If CCS can become feasible and economic, it can greatly prolong the use of fossil fuels in power generation since their GHG emissions would be significantly reduced. While CCS works in laboratories and demonstration projects, it has yet to be demonstrated in wide-scale commercial operation. Initial projects have struggled to get the technology to work well and to get projects built and running without wildly exceeding estimated costs.

So, the coal industry is celebrating as the new Petra Nova project comes online on time and on budget. This project is jointly owned by NRG and JX Nippon Oil and Gas, and it was installed on NRG’s existing WA Parrish generation station. In the new CCS plant, the exhaust waste from the electric generating station is run through a vessel containing a solvent called amine. Amine captures the CO2. The amine/CO2 mixture is then removed from the stream, the CO2 is separated by heating, and then pumped into a pipeline. The pipeline delivers the CO2 to a nearby oil field for use in a common process called enhanced oil recovery, which stimulates oil production. Since the process will result in oil production that was otherwise not possible, NRG estimates that at an oil price of at least $50/barrel, the process will prove economic[3].

Here’s a visual representation of how the process works as reported by U.S. News and illustrated by NRG:

source: http://www.usnews.com/news/articles/2014/09/17/carbon-captures-moment-in-the-sun

Does CCS have the opportunity to significantly reduce GHG emissions?

The role CCS plays as a widespread tool in reducing GHG emissions will depend on proving that the technology will work well in the field and in bringing down costs. Initial installations of any technology are always expensive. NRG estimates they can bring down costs for the next installation by 15%, but this likely isn’t enough to lead to many installations; costs will have to come down more substantially.

A recent study by the International Energy Agency, however, suggested that about a third of China’s existing 900 MW fleet of coal units could meet basic criteria for being suitable for a retrofit[4].  So although applications for CCS must still be proven, there is the possibility that use of CCS could become widespread through retrofits on existing coal plants.  In addition many in the industry believe that CCS may be a solution for reducing GHG emissions from natural gas units that provide needed flexibility to grids with large amounts of renewable power. Given these factors, there is strong industry interest in developing the technology, and initial projects will be closely watched to help determine whether CCS can become a part of our future.

Footnotes:

[1] See ‘Utilities vote to close 2,250 MW Navajo plant, largest coal generator in western US’ at http://www.utilitydive.com/news/utilities-vote-to-close-2250-mw-navajo-plant-largest-coal-generator-in-we/436222/ and ‘DPL settlement to close two power plants, shift to green energy’ at http://www.bizjournals.com/dayton/news/2017/01/31/dpl-settlement-to-close-two-power-plants-shift-to.html

[2] See ‘China’s war on coal continues – the country just cancelled 104 new coal plants’ at  http://www.vox.com/energy-and-environment/2017/1/17/14294906/china-cancels-coal-plants

[3] For more detail on how the process works, see the video available at https://www.youtube.com/watch?v=GGnGZ6pLzLU

[4] See ‘The potential for carbon capture and storage in China’ at https://www.iea.org/newsroom/news/2017/january/the-potential-for-carbon-capture-and-storage-in-china.html