Updated – January 2017: In October 2016, Squamish Nation Chiefs and Council voted to select air cooling as the cooling technique Woodfibre LNG Limited will use to cool its LNG facility. Find out more: woodfibrelng.ca/squamish-nation-announces-decision-on-woodfibre-lng-plant-cooling-technology/.
Thank you for your question.
Just to clarify, at Woodfibre LNG, we are proposing to make Liquefied Natural Gas (LNG) and not Compressed Natural Gas (CNG).
As with any refrigeration system, heat of compression must be removed from the system in order to make the process work and improve the efficiency. As part of our early design work, we asked WorleyParsons (2013) to conduct a study on suitable types of cooling medium options available to the Woodfibre LNG Project.
During the course of the study the following cooling medium options were investigated;
- Air Coolers
- Evaporative Coolers (including cooling towers, wetted surface air coolers and hybrid wet / dry wetted surface air coolers)
- Fresh Water Cooling from local streams
- Seawater cooling from Howe Sound
In selecting a preferred cooling method, Woodfibre LNG considered environmental effects, regulatory issues, and capital and operating cost considerations (e.g. maintenance, reliability, energy efficiency).
Woodfibre LNG’s selection of a seawater cooling medium was amongst the most expensive options studied, and was chosen based on the following;
- Most efficient medium and consistent temperature
- Least amount of visual impact
- Least amount of noise impact
- Least amount of footprint (approximately 100m2 of required area for seawater cooling versus 1000m2 of required area for cooling towers and over 2000m2 for air coolers)
Cooling towers also require the addition of water treatment chemicals to avoid scaling, biofouling and corrosion and also require mitigation against Legionellosis (Legionnaires Disease).
A summary of the results of the study on cooling mediums can be found in our Environmental Assessment Certificate application in 2.4.6 Alternative Cooling Technologies. You’ll note that it does not include costs as that is not public information at this time.
To learn more about our proposed seawater cooling system, please see our seawater cooling information sheet.