Blatchford District Energy SHX

Architecture, Infrastructure, Award-Winning, Public, Edmonton, In Progress, Landscape

Located on decommissioned airport lands, the Blatchford Redevelopment is anticipated to be Canada’s first carbon neutral community. Future home to up to 30,000 Edmontonians, the community will receive over 90% of energy from renewable sources. The Blatchford Sewer Heat Exchange (SHX) Energy Centre is one of several energy centres designed to provide renewable energy for heating, cooling and domestic hot water to the Blatchford community through the District Energy Sharing System (DESS). Using state-of-the-art technology, the Blatchford SHX will extract thermal energy from the 2400mm combined sewer trunk located on the site. Sharc 880 packaged units for solids removal and heat exchange, along with several heat pumps, will together provide an average February heating capacity of 6,600 kW and an average August cooling capacity of 10,300 kW.

The energy centre will be located at a gateway corner for the Blatchford Community, at the intersection of Princess Elizabeth Avenue NW and 109th Street NW. In its highly visible location, the building will make a compelling argument for architecture’s aesthetic function: to contribute to the public awareness of the human effect on the urban environment. Through its formal expression, the building celebrates the civic potential for urban energy infrastructure as a landmark and signifier of the ecological complexities of daily experience within the public realm, in contrast to treatments of municipal infrastructure that are buried or housed within disguised enclosures.

Situated between two sewer easements to the north and south, the Blatchford SHX Energy Centre realizes an integrated approach to the design of the architecture, program, and site strategy: the building visualizes the processes that are occurring below grade, signals its role within the District Energy Sharing System (DESS), and defines a variety of public plaza spaces at an important urban corner.

The site landscape consists of majority hardscape to keep tree roots distanced from underground infrastructure, accommodate access hatches to the wet wells adjacent to the sewer line, and service vehicle access. Heavy duty permeable pavers allow vehicular access paths throughout the site—used only for periodic maintenance—to serve as a series of plaza spaces for the remaining time, maximizing the ﬂexibility of the site and increasing the opportunity for a variety of public functions. The paver pattern will be a prominent element on the site, unified with the building design to render the infrastructural function legible, didactic, and aesthetically compelling: the pattern continues the footprint of the tube forms to the site extents and highlights the footprint of the lift station below ground.

The remaining site is conceived of as an urban forest: clusters of planting inﬁll areas deﬁned by the paver pattern; they frame important views to the building, continue the street wall, and deﬁne the edges of the plaza space; together with the permeable pavers this small urban forest fulfills the goals of managing stormwater on site. The softscape, like the hardscape, follows a pixelated pattern that relates to the corbelled brick of the building. The proposed native and coniferous planting (trees and groundcover) will provide natural greens year round, pruned (limbed-up) to maintain site lines and public safety.

In subtle ways, the building engages with passers by, opening up views to its inner functions and encouraging awareness and understanding of how its systems are connected to energy use in the broader community. By elevating the architecture to that of an important public landmark, the design of this energy centre endeavors to popularize its sustainable mandate and communicate the building’s critical public role.

The building uses a minimal material palette to showcase its monolithic volumes. Thin white brick with a dark grout has a streamlining effect and emphasizes the horizontal movement of the building. Offsets in alternating rows of brick create a gradient textured effect for the chimney facade. Higher up the chimney, the degree of offset increases.

The two 7m x 7m tube volumes are hollowed out at their ends with large corbelled soffits that draw the eye inwards towards the building interior, with views exposing the building’s infrastructure below. The interior material palette provides a minimal and ubiquitous backdrop to the mechanical equipment: abuse-resistant drywall painted white, concrete ceilings painted white, and smooth, exposed concrete floors.