INNOVATION May-June 2017

Alexandra District Energy Utility expands with Phase 4

Yukon’s hydro-based electrical system is isolated from North America’s grid. Delivering a continuous source of electricity is challenged by spikes in demand due to weather, transmission and hydro-generation failures. Yukon Energy Corporation’s aging diesel backup generators increasingly present a reliability risk. The corporation, with First Nations support and a $21-million investment from the Kwanlin Dun First Nation, constructed an innovative 8.8-megawatt liquid natural gas–fueled power-generating station, improving The City of Richmond retained Kerr Wood Leidal Associates to design a 1.8-megawatt low-carbon heating and cooling plant for the new Central at Garden City shopping centre in Richmond’s Alexandra neighbourhood. The plant features air-source heat pumps and condensing boilers, and will provide supplemental heating and cooling capacity to the Alexandra District Energy Utility. This is one of the first combined district heating and cooling systems in BC that uses air-source heat pumps ( shown ) and integrates with a geo- exchange system. It is also one of the only district energy systems serving large-format retail buildings. Keyera retained Sacré-Davey Engineering Inc. to design an increase in natural gas condensate storage capacity at the Keyera Edmonton Terminal. The upgrade includes four new internal floating-roof storage tanks, containment walls, a pumping system that includes associated piping and electrical power supply, instrumentation, and controls hardware and logic. To maximize storage, Sacré-Davey Engineering developed a layout providing more than twice the anticipated storage in the given space (240,000 versus 100,000 barrels). An unconventionally

reliability and reducing both power costs and environmental impacts. The capital costs associated with both diesel and LNG systems were considered along with the estimated $3- to 4-million annual fuel savings that LNG would offer compared to diesel. The LNG option also offered the distinct advantage of lower greenhouse gas emissions compared to the diesel option. APEGBC members, Allnorth: Janna Gillick, P.Eng., Stephen Noble, P.Eng. deep storage tank foundation design provides increased stability, which allows greater height-to-tank- diameter ratio. Sacré-Davey also reduced the number of flex joints in the piping system by strategically locating the pipe restraints to allow controlled pipe movement. This is expected to significantly increase the piping system’s reliability. APEGBC members, Sacré-Davey Engineering (consultant): Andrea Tylczak, P.Eng., David Pfeil, P.Eng.; Jensen Hughes Consulting Canada Ltd (sub-consultant); Keyera (owner and construction management) Once operating at full capacity, the plant is expected to reduce greenhouse gas emissions in the Alexandra neighbourhood by as much as 250 tonnes CO 2 -equivalent per year, and will provide a platform for recovering cooling energy from the mall and sharing it with nearby residential buildings. APEGBC members, City of Richmond: Kevin Roberts, EIT, Alen Postolka, P.Eng., John Irving, P.Eng.; Kerr Wood Leidal Associates: Mike Homenuke, P.Eng., Karen Sutherland, P.Eng., Robin Parker, P.Eng., Alan van der Holt, P.Eng., Padraig Harrington, P.Eng., Thomas Mah, EIT

Project improves energy reliability, lowers power costs

Upgrade maximizes storage at natural gas condensate terminal

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