Cleaning up in Alberta13 May 2021
Siemens Energy has signed an agreement with Canada-based TC Energy Corporation (TC Energy) to commission a novel sCO2 based waste-heat-to-power pilot installation in Alberta. The facility, expected to be commissioned towards the end of 2022, will capture waste heat from a gas-fired turbine operating at a pipeline compression station and convert it into emissions-free power. The electricity produced will be put back into the grid.
As part of the agreement with TC Energy, Siemens Energy will build, own, and operate the facility, with the option for ownership to be transferred back to TC Energy at a later date.
At the heart of the facility will be an innovative heat recovery process designed by Siemens Energy. The patented technology, licensed under Echogen® Intellectual Property, is based on an advanced Rankine Cycle and uses supercritical carbon dioxide (sCO2) as the working fluid to convert waste heat into power.
By deploying sCO2-based waste heat recovery solutions, midstream operators can realise greater value than traditional alternatives based on Organic Rankine or steam cycles, says Siemens Energy, whose Dresser Rand subsidiary is a partner of Echogen.
Benefits include a 25–40% smaller footprint than steam-based systems, a 10% increase in compressor station efficiency, and the capability to produce clean, emissions-free electricity. Moreover, because the working fluid is contained within a closed-loop system, no boiler operator is required, making the system suitable for remote operation.
The pilot project is supported by $8 million in funding from Emissions Reduction Alberta’s (ERA) Industrial Efficiency Challenge. For more than ten years, ERA has been investing the revenues from the carbon price paid by large final emitters to accelerate the development and adoption of innovative clean technology solutions. Since ERA was established in 2009, it has committed $616 million towards 186 projects worth $4.55 billion that are “helping to reduce GHGs, create competitive industries, and are leading to new business opportunities in Alberta.”
TC Energy is currently evaluating other compressor station sites to deploy the technology, with the potential to generate 300 MW of emissions-free power.
H class for Cascade
Meanwhile, Siemens Energy is providing its H class gas turbine technology and long-term services to the planned 900 MW Cascade power plant in Alberta, supporting the decarbonisation of Alberta’s power supply by switching from coal to natural gas.
Siemens Energy received the order from Kineticor, a developer and manager of clean power projects across Canada, with the end user being the Cascade Power Project Limited Partnership. The order value is in excess of EUR330 million. The plant is expected to begin operating in 2023.
Under the agreement, Siemens Energy is providing two SGT6-8000H gas turbines in single shaft combined cycle configuration (each with steam turbine and HRSG).
Above: SGT6-8000H gas turbine
The 900 MW Cascade power plant, near Edson, Alberta, will supply over 8% of the province’s average electricity demand.
In the power sector, Alberta contributes over 50% of Canada’s greenhouse gas emissions and as such the Cascade project represents a major emissions reduction opportunity, notes Siemens.
Repowering Milner II
Another example of the transition from coal to gas currently underway in Alberta is Maxim Power’s conversion of its Milner II power plant to natural gas. “With Alberta committed to a phase-out of coal power by 2030”, said Bob Emmott, Maxim’s president and COO, “we were faced with the reality of shuttering the facility or re-powering it with natural gas.”
The decision to repower has resulted in a new 204 MW natural-gas-fired power plant, currently the largest simple cycle natural gas-fired unit in Alberta.
Above: Gas power at Milner II
The facility employs a GE 7F.05 gas turbine, driving a GE H35 generator. The gas turbine had been in storage for eight years near a copper mine in the northern part of the United States.
GE provided relocation support and a DLN2.6+ upgrade for the turbine, and is providing services under a long term agreement.
The modernisation of the existing combustion system with GE’s DLN2.6+ technology addressed local fuel gas properties, improved plant efficiency and reduced environmental footprint to meet Canadian and local government standards. NOx emissions are less than 9 ppm.
Transport of the power generation equipment to the Milner site, by GE and FieldCore (field services company owned
by GE), posed significant challenges due to record torrential rainfall and extreme cold temperatures (reaching -40°F), compounded by the pandemic.