bnr-Modernizing-Cogeneration-to-Reduce-CO2-at-Marathon-Refinery
  1. We are WSP
  2. What we do
  3. Projects
  4. Kenai Marathon Refinery

Modernizing Cogeneration to Reduce CO₂ at Marathon’s Refinery

Our modernization of a 1980s-era cogeneration plant delivers reliable steam and electricity, cutting costs and emissions.

Location

  • Kenai, Alaska, USA

Project Status

  • Completed

To operate its refinery more efficiently and economically, Marathon wanted to expand its 1980s-era cogeneration plant to provide supplemental electrical and steam supply.

The new plant design included an 8-MW gas turbine generator that exhausts into a heat recovery steam generator duct fired to 75,000 lb/h steam with a duct burner using natural gas and refinery fuel gas to produce steam.

 

Efficiency and reliability redefined

The cogeneration unit enabled Marathon to reduce energy spending while improving the reliability of the supply of steam and electricity. We conducted early-phase project planning to guide major equipment selection and developed a total installed cost estimate to help them assess the viability of replacing existing boilers with the cogeneration unit.

Proactive planning process

Planning and integration of successful engineering design, procurement, construction and startup activities were important for Marathon’s project approach. We incorporated Advanced Work Packaging methodology into the design process to develop engineering work packages and construction work packages, aligning engineering, procurement and construction activities and deliverables.

As part of a front-end loading process, we performed a multidisciplinary design effort to support a +/- 10% cost estimate and procurement of the gas turbine generator, heat recovery steam generator, power distribution center and gas conditioning skids. We also created a Level III schedule to address the engineering design, construction and startup activities.

Lb/h steam production
75,000
MW installed
8

Cold weather design

Given the refinery’s location in Alaska, robust cold-weather design was essential. Our design incorporated the appropriate freeze protection provisions for the gas turbine generator and heat recovery steam generator so this essential equipment could be installed and operated outdoors year-round while still meeting the refinery’s continuous energy needs.

Environmental stewardship

The new heat recovery steam generator allowed Marathon to retire its aging steam boilers, reducing overall refinery CO₂ emissions. Our design incorporated a gas turbine generator bypass stack, a forced draft fresh air firing fan, a Continuous Emissions Monitoring System and space for a future carbon monoxide catalyst on the heat recovery steam generator, helping Marathon reduce emissions of its facilities and operations.

By modernizing its cogeneration plant, Marathon not only reduced CO₂ emissions but also improved energy reliability and cut operational costs — without compromising year-round performance.

Other challenges that we have overcome