Avenue Capital seeks okay for gas co-firing at coal-fired Crane Unit 2 in Maryland

C.P. Crane LLC applied June 24 at the Maryland Public Service Commission for a Certificate of Public Convenience and Necessity authorizing it to modify the existing Charles P. Crane Generating Station in Baltimore County, Maryland, to enable the use of natural gas in the existing Unit 2.

The company asked for a commission decision by the end of 2016 in order to facilitate construction by early-April 2017. This would permit the project to be in service for the summer 2017 season.

C.P. Crane is a wholly-owned subsidiary of Avenue Capital Group. The Crane plant is operated by PurEnergy Operating Services LLC.

The Crane plant includes two coal-fired units, which are the main electric generating units at the facility: Unit 1 and Unit 2. Today, both Unit 1 and Unit 2 are coal-fired. With this application, Crane is proposing to modify Unit 2 to enable it to use natural gas for electric generation, whether by itself or in combination with coal. The project will allow Crane to reduce its ozone-season (summer) emissions while maintaining electric generating capacity, reduce usage of high-maintenance coal and ash handling systems, reduce ash disposal requirements, and shorten Unit 2’s start-up time. 

Crane Station Unit 2 began operating in 1963. The unit is an opposed-wall fired, wet bottom, cyclone-burner type with a net generating capacity of 195 MW. The unit is equipped with a baghouse for control of particulate matter (PM) emissions and a selective non-catalytic reduction (SNCR) system for control of nitrogen oxides (NOx) emissions. Additionally, the boiler burners are equipped with over-fire air (OFA) systems for control of NOx. The unit also is equipped with an activated carbon injection system along with a coal additive system for control of mercury emissions and a dry sorbent injection (DSI) system for control of hydrogen chloride (HCl) emissions.

Crane Station Unit 2 is currently fired using subbituminous coal, with a maximum heat input of 1,865 MMBtu/hr. The purpose of this project is to provide natural gas firing capability on all four Unit 2 cyclones that will allow up to a maximum of approximately 50% heat input from natural gas, primarily for operation during the ozone season. The new equipment will enable firing on natural gas alone (up to approximately 100 MW), co-firing with natural gas and coal (at higher loads, up to the current unit MW rating), or coal firing alone as is done currently.

Each of the four cyclones on Unit 2 will have three new gas burners installed in the secondary air ducts, along with instrumentation and burner management controls. The gas supply system for the burners will tie into the existing Baltimore Gas & Electric (BGE) gas control station on the ground outside and adjacent to the Unit 2 boiler building via some additional piping to be installed. Each cyclone will have the capability of firing up to 237 MMBtu/hr from natural gas, for a total of 950 MMBtu/hr when all four cyclones are at maximum heat input from natural gas firing. This will utilize the full capacity of the existing BGE pipeline to the facility.

The proposed firing of natural gas in the Unit 2 boiler will not increase either the electrical generation capacity (MW) or the heat input capacity (MMBtu/hr) for Unit 2. The Project will not affect the operation of Crane Station Unit 1. 

Crane does not project any change in the short-term or annual electricity generation from Unit 2 as a result of the firing of natural gas, whether by itself or being co-fired with coal. The annual generation for Unit 2 will be determined predominantly by the market demand, and the ability to co-fire with natural gas could increase the unit’s generating potential or the market demand relative to the recent demand (e.g., 2015). However, Unit 2 must comply with the annual NOx emission limit for Unit 2 – 737 tons – stipulated under the Maryland Healthy Air Act, which will serve as an upper bound on future generation and associated fuel use or heat input of the unit.

About Barry Cassell 20414 Articles
Barry Cassell is Chief Analyst for GenerationHub covering coal and emission controls issues, projects and policy. He has covered the coal and power generation industry for more than 24 years, beginning in November 2011 at GenerationHub and prior to that as editor of SNL Energy’s Coal Report. He was formerly with Coal Outlook for 15 years as the publication’s editor and contributing writer, and prior to that he was editor of Coal & Synfuels Technology and associate editor of The Energy Report. He has a bachelor’s degree from Central Michigan University.