The Saanich Peninsula wastewater treatment plant (SPWWTP) heat recovery system was commissioned in 2011 after approximately three years of planning, design and construction. Owned and operated by the Capital Regional District (CRD), the system recovers thermal energy from treatment plant effluent and supplies hot water to heat the Panorama Recreation Centre pool.
Heat exchangers at the wastewater treatment plant transfer heat from wastewater effluent to clean water, then the temperature of the water is increased to a useable level using a heat pump system down the line. A network of pipes and pumps distributes the heated water to the recreation centre. By displacing the need for natural gas to heat the pool, the SPWWTP lowers greenhouse gas emissions from the recreation centre and reduces energy costs due to improved energy efficiency over natural gas boilers. When the system was first commissioned, natural gas prices were higher and electricity prices were lower, resulting in more significant annual energy savings. Currently, due to lower natural gas prices and higher electricity prices, the system operates at a financial breakeven point.
The heat recovery system was designed to serve more than one customer, however several potential partners backed out of the project early on. The system has capacity for more customers, so the CRD is planning for an expansion that will extend distribution to a nearby elementary school and greenhouses at the Centre for Plant Health.
According to Larisa Hutcheson, General Manager of Parks and Environmental Services, “this pilot project has served as a catalyst for the CRD to investigate and plan for four more district energy systems that would use renewable energy generated from the region’s sewer and water conveyance systems.”
The project would not have been achievable without the support of internal stakeholders, including the Peninsula Recreation Commission, Saanich Peninsula Wastewater Commission, and CRD employees, including engineers and staff at the Panorama Recreation Centre and the Saanich Peninsula Wastewater Treatment Plant.
The Regional District has noted the following important lessons, which other communities could learn from if implementing similar projects:
o Consult with operators and staff to design the system
o Identify partners with a common interest in lowering energy costs and GHG emissions and make the project scalable. The CRD allowed for future expansion to two sites.
o In addition to a feasibility study, create a strong business case that articulates triple-bottom-line benefits to gain supporters and “normalize” green investments.
o Provide community outreach and education to minimize potential misunderstandings related to waste heat recovery.
11,250 GJ of natural gas saved per year, or the equivalent consumption of about 220 Saanich residences.
Prevents approximately 370 tonnes of GHG emissions from entering the atmosphere annually
Approximately $60,000 saved in operation and maintenance costs from 2011 to 2013
Reduced exposure to a price on carbon
Greater resiliency against increasing energy costs and service disruptions
Catalyst for four additional district energy systems using renewable energy
Employment during project construction
Designed with capacity to serve a greenhouse and elementary school in the area in the future
Total project cost:
Nearly $3 million from the federal Gas Tax Fund