Rackam generates cold from the sun's energy and is awarded a Technoclimat grant
2 December 2015
A provincial grant of nearly $400,000 from the Technoclimat program has just been awarded to Rackam by Quebec’s Ministry of Energy and Natural Resources of Quebec. This grant recognizes the excellence and innovation of the Alouette Building’s new hybrid power plant. Located on the UQAC campus in Sept-Îles, the building was designed by the architectural firm BGLA + Design Urbain and its new power plant will be fully operational as of January 2016.
This new project from Rackam perfectly meets the objectives of the Technoclimat program to reduce greenhouse gas emissions and encourage the development of new technologies in energy efficiency and emerging energy sources.
As a matter of fact, in partnership with the CanmetENERGY federal research laboratory in Varennes, Rackam has performed a world-first: the production of cooling with solar energy! This new facility will allow the building to be air conditioned and heated all year round using solar and geothermal energy.
The hybrid system consists of an ultra-modern solar concentration field on the building’s roof, which is made up of 15 rows of S10 concentrators totaling 214 m² of parabolic mirrors, as well as several geothermal wells around the site.
Throughout the winter, the solar field will capture luminous energy and transform it into heat to supply the building, which can accommodate 400 occupants. The geothermal wells will complement the solar heat supply.
In summer, it will be a world premiere: the system will produce cooling from solar energy, with a new thermally activated ejecto-compressor system for the building’s air conditioning needs.
But how do we create cold using the heat from the sun?
In a conventional system, electrical energy drives the heat pump, which in turn transfers heat from one energy system to another. In a thermally activated ejecto-compression system, the heat produced by solar concentrators powers the pump, an ejecto-compressor developed by the CanmetENERGY team.
When the coolant, heated by the solar field, passes through this metallic part with specific geometrical properties, the tapered neck combined with a constant pressure produces supersonic acceleration over a very short distance. The acceleration of the fluid in turn produces depressurization (the Venturi principle). This creates a vacuum which pumps refrigerant through the system, replacing the standard compressor found in a “normal” refrigeration cycle.
The ejecto-compressor is connected to the other usual components in a refrigerant circuit: a condenser, an expansion valve and an evaporator. The evaporator is the element that produces cold (evaporation requires energy). In the case of the Alouette Building in Sept-Îles, the system will circulate a water-glycol solution to cool the evaporator, and the same fluid will cool the building during the summer.
In addition, as is the case in a refrigerator, the system’s condenser produces heat. Rackam came up with the idea to connect the condenser to another fluid circuit to recover this heat and store it for winter, through the installation of geothermal wells. Connecting this second circuit to geothermal wells allows them to heat up, thus “recharging” them. The geothermal wells will consequently see heat storage capacity and durability increased (keep in mind that geothermal wells become less and less effective over time if not recharged).
Ultimately, this hybrid solar plant will be capable of delivering 100 kilowatts of solar thermal power and 27 kW of cooling power production, for a total annual energy production of 129 MWh.
Work began this summer and the new hybrid power plant will be inaugurated inj january.
A Photo of the Alouette building in Sept-Îles with Rackam’s solar concentration field on its roof