TransAlta is an electrical generation facility operator and developer headquartered in Calgary, Alberta. The company has been recognized for its leadership in sustainability and is Canada’s largest investor-owned renewable energy provider. In December of 2021, TransAlta shut down the last of its domestic coal-fuelled thermal power generation facilities as part of its coal-to-gas conversion and its commitment to 100 per cent natural gas operation by the end of 2021 in Alberta. TransAlta has retired 3,794 MW of coal-fired generation capacity since 2018 while converting 1,659 MW to cleaner burning natural gas while maintaining full power generation capacity. Overall, the converted units generate nearly 50 per cent fewer CO2 emissions fueled by natural gas compared to coal. This project is a significant achievement for TransAlta towards its target to reduce 60 per cent, or 19.7 million tonnes, of annual greenhouse gas emissions by 2030 over 2015 levels and achieve carbon neutrality by 2050.
Gas Conversion Projects Acoustical Support
To undertake these successful large-scale thermal power generation facilities gas conversions TransAlta appointed Fossil Power Systems (FPS) to be the engineering, procurement and construction (EPC) contractor. FPS is a leader in turnkey gas conversion projects having completed over 50 natural gas conversions on boilers in North America managing all aspects of the conversions including detailed design, manufacturing, construction and commissioning. FPS sub-contracted HGC Engineering to provide workplace noise and gas piping noise assessments at TransAlta’s Keephills and Sundance Power Stations both located near Wabamun, 70 km west of Edmonton, Alberta, Canada. Both facilities had recently undergone coal-to-gas conversion.
Assess Equipment Sound Pressure Levels
HGC Engineering visited the TransAlta Keephills Unit 2 Generating Station to assess the sound levels from equipment related to the transition of Unit 2 to gas fuel. Specifically, detailed sound level measurements were requested for the C-Elevation Gas Header for Unit 2 in order to create a rank ordered list of dominant sound sources. Previously, HGC Engineering completed detailed measurements of the recently installed gas equipment. It was requested that sound pressure levels be determined at 1 metre from the burner shutoff valve trains, the three gas headers and the main ignitor gas header for comparison to the specifications for the installation of the gas equipment.
Conduct Sound Intensity Measurements
It was observed that there were significant contributions of sound from many items of equipment within Unit 2 that were not part of the systems under test, such that straightforward sound pressure level measurements at 1 metre from each piece of equipment would have included significant contributions from these other, extraneous sources. Therefore, Sound intensity measurement techniques were employed to determine the sound levels from the selected equipment. Sound intensity measurement instrumentation has a high inherent ability to reject extraneous sounds originating from outside the measurement control-volume, and can therefore separate the sound emitted by each component.
Like at Keephills, HGC Engineering visited TransAtla’s Sundance Generating Station to assess the sound levels from equipment related to the recent transition of Unit 6 to gas fuel supply. Specifically, it was requested that sound pressure levels be determined at 1 metre from the burner shutoff valve trains and the three gas headers for comparison to the specifications for the installation of the gas equipment. Sound intensity measurement techniques were employed to determine the sound levels from the selected equipment.
Acoustical Engineering Services Included:
- Preparing an assessment, based on individual source measurements on site, following commissioning using sound intensity measurement techniques
- Assessing sound levels of coal-to-gas conversion equipment upgrades and expansions to the facilities
- Conducting Workplace Noise Assessment