DTE Electric, a subsidiary of DTE Energy (NYSE: DTE), told the Michigan Public Service Commission in its Sept. 30 annual Power Supply Cost Recovery (PSCR) case that it retired some coal capacity this year and plans to retire more beginning in 2020.
John O. Yurko, employed by DTE Electric as a senior technical specialist in the Generation Optimization Organization, wrote: “The total capacity from Company-Owned generation in 2016 is 12,086 MW, which reflects the retirement of River Rouge Unit 2 which retired in 2016. In 2017, the Company is projecting an increase of 125 MW in owned capacity resulting from 51 MW of additional owned wind generation, 50 MW of additional owned solar generation and 24 MW from the Ludington [pumped storage hydro] upgrade project.
“In 2018, the Company is projecting an increase of 29 MW in owned capacity resulting from 5 MW of additional owned solar generation and 24 MW from the Ludington upgrade project.
“In 2019, the Company is projecting an increase of 184 MW in owned capacity resulting from 150 MW of additional owned wind generation, 10 MW of additional owned solar generation and 24 MW from the Ludington upgrade project.
In 2020, the current projection is to retire the remaining generation at the River Rouge Power Plant – that is, River Rouge Unit 3 (280 MW) as well as the peaking generation at this site (11 MW) – for a total decrease of 291 MW. This will be slightly offset by a projected 10 MW increase in owned solar generation and 24 MW from the final Ludington unit upgrade for a total net decrease of 257 MW in 2020
“In 2021, the Company is projecting an increase of 150 MW in owned capacity resulting from an additional 150 MW of owned Wind generation.”
Ryan C. Pratt, Supervisor, Planning and Procurement within the Fuel Supply department, wrote about coal supply: “The long-term forecast of coal prices assumes the Company’s continued reliance on lower delivered cost low sulfur western (LSW) coal. For 2017, about 84% of all coal tonnage consumed is projected to be LSW coal. The LSW coal is procured from the Powder River Basin, which is located in southern Montana and northeastern Wyoming. The balance of the Company’s coal is purchased from Central and Northern Appalachia. Coals from this region include high sulfur eastern (HSE) and low sulfur southern (LSS).
“In 2016, DTE Electric retired Trenton Channel Unit 7A and River Rouge Unit 2. Additionally, the Company plans to retire Trenton Channel Unit 9, River Rouge Unit 3, and St. Clair Units 1-4 and 6-7 between 2020 and 2023. The retirement of the remaining Trenton Channel, River Rouge, and St. Clair units will decrease DTE Electric’s generation capacity by approximately 2,200 MW. Additional coal-fired generation may be retired by 2030.
“These above coal unit retirements support the Company’s expectation of a fundamental shift from a heavily weighted coal generation fleet to more natural gas-fired and renewable generation that is primarily driven by new environmental regulations. Accordingly, DTE Electric expects that natural gas combined cycle gas turbine (CCGT) generation will be the most economic source of replacement baseload generation.”
Barry J. Marietta Jr., employed by DTE Energy Corporate Services LLC within Environmental Management & Resources as a Manager–Air Quality Services, wrote about federal Mercury and Air Toxics standards (MATS) compliance: “The rule provides a three-year implementation for compliance with limits set forth making the initial compliance date April 16, 2015. However, DTE Electric applied for and received one-year extensions to the compliance date at its coal-fired power plants: Belle River, Monroe, St. Clair, River Rouge, and Trenton Channel. Therefore, the compliance deadline for those five plants was April 16, 2016.
“DTE Electric is utilizing [activated carbon injection (ACI)] technology at Belle River, St. Clair, River Rouge and Trenton Channel Power Plants for the control of mercury emissions as required by the MATS regulations. The installation of the ACI equipment was completed prior to the MATS compliance date. Monroe is utilizing the previously installed [flue gas desulfurization (FGD)] and [selective catalytic reduction (SCR)] equipment to control mercury emissions required by the MATS regulations. Reduced Emission Fuel (REF) is currently being utilized at Belle River, Monroe and St. Clair to enhance the control of mercury emissions.
“The HCl emission limit requires additional emission reduction technologies. FGD has been proven to meet the MATS acid gas limits and is installed and operational on all four Monroe Power Plant units for MATS compliance. FGD, while an effective acid gas removal technology, is a technology that requires a significant capital investment. This larger capital investment, however, was prohibitive on the other coal-fired Electric Generating Units (EGUs) in the DTE Electric portfolio. A less capital investment intensive technology to the installation of FGD is dry sorbent injection (DSI). HCl compliance is achieved using DSI technology on coal fired units other than Monroe Power Plant in the DTE Electric portfolio.
“The DSI and ACI systems at Belle River, River Rouge, St. Clair and Trenton Channel Power Plants have been used for MATS compliance since the compliance date of April 16, 2016.
“During performance testing of the equipment, it was discovered that compliance level mercury reduction could not be consistently achieved using BrPAC on Trenton Channel Power Plant Unit 9 because of unit design limitations. A calcium bromide (CaBr) injection system was installed to provide additional halogen (Br) beyond that provided by the BrPAC. This additional halogen ensures the necessary mercury oxidation for adsorption by the PAC.”