Document jyLJ3qr9NOg5R00gj402ozx02

To: From: Sent: Subject: Gunasekara, Mandy[Gunasekara.Mandy@epa.gov] Eames, Frederick R. Fri 4/7/2017 4:12:50 PM RE: Coal technology You mentioned three types of technology you would like to discuss: - High efficiency low emission (HELE) technology - Ultra supercritical technology (USC) - Integrated gasification combined cycle (IGCC) Here's some quick background. - HELE technology is a broad category. Probably the two main technologies under HELE would be the other two categories above - USC and IGCC. There are other types, but those are the main two. - USC needs some brief explanation. An "ordinary" coal-fired power plant is fired by pulverized coal. The coal is smashed into powder and combusted in a chamber. The heat turns water to steam, and the steam turns a turbine. Plants before about the mid-80s, I believe, were subcriticai. They had an efficiency of turning coal into power of about 33%. Supercritical plants operate at higher temperature and pressure and might have an efficiency of 37-40%. Ultrasupercritical plants operate at even higher temperature and pressure and might have an efficiency of 45% or so. To get to the higher temperature/pressure you need different metallurgy, design, etc. - IGCC doesn't burn the coal, it essentially bakes it under pressure. The result is a set of chemical streams - a syngas that gets burned to produce power, CO2, and some other streams that typically are turned into fertilizer or its components. There are only a few large IGCC facilities for electricity in the US: Edwardsport (Duke, IN), Polk (TECO, FL), and Kemper (Southern, MS). There are a number of smaller ones that use biomass. --Original Message-- From: Gunasekara, Mandy [mailto:Gunasekara.Mandy@epa.gov] Sent: Friday, April 07, 2017 11:41 AM To: Eames, Frederick R. Subject: Coal technology Can you send me the types of coal technology that Roxann will be briefed to discuss? Sent from my iPhone 17cv1906 Sierra Club v. EPA ED_001523A_00000328-00001