First things first – what exactly is a sustainable community? Well, there is no single blueprint for designing a sustainable community, but fortunately, we can define them by the goals they aim to accomplish. Going one step further than net-zero buildings, sustainable, or green, communities are gaining popularity throughout the world.
Kaid Benfield, the Sustainable Communities program director at the Natural Resources Defense Council, defined the term for us. In the Scientific American, he said they are places “where use of resources and emissions of greenhouse gases and other pollutants are going down, not up; where the air and waterways are accessible and clean; where land is used efficiently and shared parks and public spaces are plentiful and easily visited; where people of different ages, income levels and cultural backgrounds share equally in environmental, social and cultural benefits; where many needs of daily life can be met within a 20-minute walk and all may be met within a 20-minute transit ride; where industry and economic opportunity emphasize healthy, environmentally sound practices.”
It almost sounds too good to be true. Almost.
Blatchford presents a hopeful look towards a sustainable future as it sets out to build such a community. Located in the heart of Edmonton, Canada, it encompasses 536 acres and aims to be a model for a green, 100% renewable, carbon-neutral community.
Their vision, as stated on their website, declares:
Blatchford will be home to up to 30,000 Edmontonians living, working and learning in a sustainable community that uses 100% renewable energy, is carbon neutral, significantly reduces its ecological footprint, and empowers residents to pursue a range of sustainable lifestyle choices.
While several factors play into fulfilling these sustainability goals, two of the major ones are infrastructure and technology; these tie directly into their energy strategy.
Their energy strategy focuses on energy conservation and energy efficiency. As such, the energy system is uniquely designed to reduce environmental impact. To reduce greenhouse gas emissions, a public, city-owned utility owns and operates a District Energy Sharing System (DESS) that is tasked with providing eco-friendly heating, cooling, and hot water to the buildings and homes. By sharing energy between these buildings, Blatchford will reduce overall energy consumption across the community and produce roughly 75% fewer GHG emissions than a standard residential community. Not too shabby in terms of sustainability!
HEAT PUMP DESIGN
To accomplish this hefty goal, CIMCO Refrigeration designed a heat pump to be housed in their energy station. The aim was to generate heated recirculated water for five swimming pools in the Community Center, using recycled water from the local water treatment plant as its geothermal source.
The parameters for the design/build were basic:
- Heating and Cooling Cycle
- Geothermal Source
- 250 TR Capacity
- Coefficient Of Performance > 10
- Ammonia Refrigerant Low-Charge Acceptable
Energy Centre One is the home of the planned energy station, including this heat pump. It’s located in the heart of Blatchford, in a decidedly public and pedestrian-friendly area. The prominent location was chosen on purpose – so that residents and visitors could see where the community energy comes from. It’s not every day that one gets to see a renewable energy source in action!
The heat pump was provided according to specifications, with the capability to provide maximum 1070 KW or 4 Giga Joules of heat based on a geothermal flow rate of 780 us gpm or seasonal cooling of 3120 MBH at full capacity.
The heat pump is reversible - it provides building cooling glycol in summer and heated glycol in winter.
In winter, the system is designed to operate at 58°F ammonia discharge temperature and 18°F suction temperature. It provides 250 TR using a geothermal ground loop for chilling and provides a 50°F fluid source as a heat source for the housing development to operate individual small-scale residential heat pumps.
In summer, it has a range to operate at 40°F suction to 90°F condensing using ground source geothermal. It provides a 45°F circuit for summer air conditioning up to 350 TR, as conditions require. Ammonia flow is reversible from plate to plate, changing from chiller to condenser and back. This eliminates any brine or water flow changes in the plate and any concern with flow rates. The plates are designed to operate as necessary at different pressures and temperatures.
Each building has a heat-pump based energy transfer station, which extracts thermal energy from the DESS and upgrades for building’s heating, cooling and domestic water needs. Heat pumps upgrade energy more efficiently than a typical furnace.
As the development progresses, it will be home to three heat pumps and two more energy centers.
CIMCO is very proud to be a part of this community project. As we expand our products and offerings to focus on more sustainable solutions, we hope that more projects like Blatchford will be the way forward to a greener, cleaner future. In the meantime, residential construction is underway in Blatchford, and it is well on its way to becoming Edmonton’s first sustainable community!