Aerial view of the site of proposed Topolobampo II power plant to be built by Spanish company Iberdrola. Credit: Iberdrola.
The Topolobampo II plant will be located in the municipality of Ahome in Sinaloa state, Mexico. Credit: Iberdrola.
The Noroeste power plant will be equipped with two MHPS J-Series gas turbines. Credit: Mitsubishi Hitachi Power Systems Americas.

Noroeste is a natural gas-fired 890MW combined-cycle power plant proposed to be built by Iberdrola for Comisión Federal de Electricidad (CFE), the electric utility of Mexico. The project is also known as Topolobampo II combined-cycle plant.

The plant will be built in the municipality of Ahome at the Topolobampo port in Mexico’s Sinaloa state. It is expected to provide electricity to approximately three million customers in the country.

A contract for the construction, commissioning, operation and maintenance of the power plant was awarded to Iberdrola in June 2015. Iberdrola will own the plant and will sell the electricity under a 25-year power purchase agreement (PPA) signed with CFE in April 2016.

The project is estimated to be completed at a cost of $400m and scheduled for completion in January 2019.

Project details of the Topolobampo II Thermoelectric Plant

The combined-cycle power plant is part of a two-stage project that also includes Topolobampo III. Adding a generating capacity of 680MW, the second stage of the project will be built adjacent to the first stage.

Iberdrola will also install facilities such as the power lines and transformer substation in order to connect the power plant with the Mexican electricity grid. The project also includes the construction of a new substation.

Turbine details of Topolobampo II power plant

Mitsubishi Hitachi Power Systems (MHPS) will install two 327MW M501J gas turbines in the plant. Each turbine is capable of operating at a frequency of 60Hz. A MHPS TC4F steam turbine will also be supplied by the company.

The M501J turbine measures 14.4m long, 5.4m wide and 5.7m high. The 320t turbine will operate at a rated speed of 3,600rpm and is capable of operating at a turbine inlet temperature of 1,600°C.

The compressor of the turbine will have 15 stages. The effect of thermal expansion on alignment will be reduced by the turbine’s compressor shaft end drive, which will also avoid the need for flexible couplings. To ensure optimisation of the plant layout, the exhaust of the turbine will be structured in the form of an axial flow.

“The project is estimated to be completed at a cost of $400m and scheduled for completion in January 2019.”

The turbine ends and the compressor will be supported by the long two-bearing structure of the rotor. Each turbine will comprise one rotor and four turbine stages. The rotor unit will contain bolt-connected discs and torque pins in the compressor rotor. The discs with curvic couplings in the rotor will enable reliable torque transmission.

The plant, when installed with one on one turbine configuration, will deliver an output of 470MW with 61.5% lower heating value (LHV) efficiency, whereas during two on one operation, the output of the plant will be 942.9MW with 61.7% efficiency.

Sustainable features

The turbines to be installed on the plant will use natural gas resources. The plant will emit less nitrogen oxide, carbon monoxide, unburned hydrocarbons (UHC) and volatile organic compounds.