Press Information

MPSA Successfully Completes SCR System Performance Testing at Large-scale Gas Turbine Power Generation Plant in the U.S.
- Milestone Achievement for 200MW Class Simple-Cycle Gas Turbine -


Tokyo, July 30, 2013 - Mitsubishi Power Systems Americas, Inc. (MPSA), the business base for Mitsubishi Heavy Industries, Ltd. (MHI) power systems operations in the U.S., has successfully completed verification testing of a large-scale Selective Catalytic NOx Reduction (SCR) system, which is to be installed at an 800 megawatt (MW) large-size gas turbine simple-cycle power generation plant. The testing was performed at the Marsh Landing Generating Station in Antioch, California, site of four 200MW gas turbines, and MPSA's SCR system reduced gas emissions, including nitrogen oxides (NOx) and ammonia, within compliance limits. The event marks a milestone achievement for the SCR system, demonstrating its capability to meet emission limits with a 200MW class simple-cycle gas turbine.

The Marsh Landing Generating Station is situated in the San Francisco Bay Area, where some of the world's most stringent air quality control limits are imposed on emissions of NOx, ammonia, carbon monoxide (CO), volatile organic compounds and particulate matter. MPSA's SCR system successfully demonstrated the ability to keep within emission limits during quick starts and load changes and with gas turbine loads across the entire 0% to 100% range.

The SCR system tested features a system to cool the gas turbine exhaust gas from approximately 600 degrees centigrade (°C) to below 460°C. The cooling system was achieved by introducing technology that uniformly mixes hot exhaust gas and air – the coolant – and by utilizing a structure that protects ducts through which air is directed to the exhaust gas from the thermal stress. Also adopted in the SCR system are new structural and control systems designed to accommodate quick starts and load changes, and an ammonia vaporization system that utilizes exhaust heat.

The Marsh Landing Generating Station was built as a backup power plant to meet fluctuations in large-scale renewable energy power generation and peaks in power demand. Recently, there has been a sharp increase in the need to develop energy sources for backup and power peaking in order to cope with heavy demand in summer. Conventionally, small-size gas turbines and gas engines have mainly been adopted in backup power plants; however, deployment is gradually increasing of large-scale backup plants like the Marsh Landing Generating Station.

Although the newly tested SCR system is for a gas turbine simple cycle power generation system - and not for a gas turbine combined cycle (GTCC) system, which uses a gas turbine and steam turbine in combination to generate power - the successful test results will lead to further adoption of the SCR system to meet emission controls on large-scale gas turbine simple cycle power generation plants, which are widely used in the U.S. The SCR system is also expected to be in demand in new backup power plants for renewable power generation and scaling up of plants to accommodate power peaks.

MHI is a pioneer in NOx emission control technology, having supplied more than 600 SCR systems worldwide. For more than 40 years, the company has provided advanced emission control systems for power boilers, gas turbines, refineries and process heaters burning all forms of liquid, gas and solid fuels.

Going forward, MHI will continue to proactively respond to diverse emission control needs, including those imposed on large-scale gas turbine power generation systems.