Noise control study, and noise abatement design for simple cycle power plant expansion located in close proximity to residential properties in Eastern Canada.
SCOPE OF WORK
Initially, INNOVA was retained to conduct a noise control study for the installation of two simple cycle 50MW gas turbine generators at the facility. The study showed that the most cost-effective means to meet the required regulatory noise levels for the project was to retrofit the existing 350MW thermal generating plant to allow for noise contribution from the new units.
A combination of treatments including, a noise barrier wall, highly acoustic rollup doors, and building ventilation silencers were installed to achieve the reduction required to meet regulatory noise levels.
Following the installation of the second 50MW turbine generator, nearby residents expressed dissatisfaction with environmental noise from the facility. INNOVA was retained to conduct an additional noise impact study find a means to reduce annoyance in the community due to noise. INNOVA conducted a detailed analysis of the new units, long-term noise monitoring in the community, and met with residents to discuss their concerns. Although the plant was found to be marginally within its required noise levels several noise issues were identified.
- The new turbine units are emitting low-frequency noise at an undesirably high level.
- The characteristic frequency distribution of A-weighted environmental noise in the community has changed. Residents are opposed to the characteristic sound of the new units.
- The new units were emitting excessive noise during winter operation.
Recommendations for reducing community annoyance due to noise from the new units have been made including establishing a stringent noise reduction target for noise emission from the turbines to make them less dominant in the acoustic environment and to reduce their low-frequency noise emission. Additional noise abatement measures are planned for the turbine units and INNOVA continues to aid the Client in developing a noise abatement strategy compatible with their long-term plans for the facility.
50 dBA at 800 feet at the nearest residence.
This is a complex acoustical environment situated in an urban environment with mixed residential, commercial, and industrial land uses nearby. Traffic noise is present on several nearby roadways as well as rail and ship noise. Facility equipment includes:
- Thermal generating facility consisting of three units totaling approximately 350MW
- Two 50MW simple cycle gas turbine generators
UNIQUE PROJECT HURDLES
A complex acoustical environment involving many sources of environmental noise, a frequently changing marine climate, and topography involving a receptor uphill from the noise source make measurement and design for this site challenging. Making an immediate improvement in the acoustic environment as well as incorporating the Client’s long-term plans for the site make design challenging. The design also addresses specific resident complaints instead of meeting general noise regulation requirements.
This project is currently ongoing. Some noise abatement measures have been successfully installed, others are planned for the near future and as the client's site development plan proceeds.