You can hear a soft hum outside the boiler room door of a new condominium development in southeast Calgary.
Other than that sound, no one in this quiet residential community would know they’re living next door to a revolutionary energy source for homes and offices. Inside the boiler room is a tiny turbine with a coffee can-sized generator.
Turning at 96,000 revolutions per minute, the micro-turbine is producing enough heat, hot water and electricity to supply the 12-unit condominium being built in Inglewood.
Walker Court is the first energy-efficient and environmentally friendly home-office project of its kind in Canada. The condo’s energy needs are supplied onsite, with a natural gas-powered micro-turbine clean-air heat and power system.
“We’ve invented a new business model. We call ourselves a distributed micro-utility,” says Richard Adamson, vice-president and chief operating officer of Mariah Energy Corp. in Calgary.
Company president and chief executive Paul Liddy says that compared with conventional energy sources, Mariah’s patented Heat PlusPower system “offers triple the efficiency, near-zero emissions, heat and power costs lower than utility rates and protection from (power) outages.”
Mariah Energy is a subsidiary of Suncurrent Industries Inc., the developer of Walker Court. Suncurrent is a Calgary-based construction contractor and developer of commercial real estate projects.
Walker Court is a pilot project to demonstrate the technology of co-generation — using one energy source to generate both heat and power. The federal government, through its Climate Change Action Fund and the National Research Council, is contributing more than $150,000 to the project.
Walker Court’s micro-turbine is connected, through ENMAX, to the city of Calgary’s electrical grid. During peak power demand times — a couple of hours each day when condo residents require more electricity than the turbine produces on site — the extra power is drawn from the city’s grid. The rest of the time, when the turbine generates more electricity than the condo requires, the surplus power is sold back into the grid.
But Walker Court isn’t just about using “greener” energy, Adamson says. The economics have to make sense, too. “For the most part, if you can’t save money (for customers), you’re not going to get out of the starting block.”
For a long-term price that’s cheaper than utility costs, condo residents will get heat and electricity even if there’s a power failure on the city’s grid. The turbine also provides back-up and emergency power for business tenants, such as a computer software developer that has just bought one of the condo units.
Adamson, who worked in the field of industrial process control systems before starting Mariah Energy with Liddy, says the company spent a lot of time looking for the best micro-turbine technology.
Capstone Turbine Corporation in California makes the 30-kilowatt micro-turbine that is the heart of Mariah’s energy system. The machine is a compact 1.8 metres x 1.2 m x 0.75 m and it weighs less than 495 kilograms.
Mariah has further soundproofed the already quiet-running micro-turbine so it is well within the city’s allowable night-time ambient sound level. It was easy, for example, to hold a conversation inside the boiler room.
The micro-turbine can run on a wide variety of fuels, including natural gas, propane, diesel, liquid fuel such as kerosene, landfill gas or sewer gas. Running on natural gas, the machine operates at a combined efficiency (both heat and power utilized) of well over 85 per cent — meaning its emissions are “ultra-low.”
The tiny turbine produces about 55 per cent less greenhouse gas emissions than conventional energy sources. That adds up to a reduction of 184 tonnes per year of carbon dioxide emissions, compared with coal-fired electricity that supplies more than 90 per cent of Alberta’s power requirements.
The micro-turbine’s generator, which has only one moving part, is air cooled and lubricated by air bearings. “It can run 24 hours a day the year round” with minimum maintenance, Adamson says.
To provide the heating component of its system, Mariah Energy installed its own custom-built heat recovery unit on top of the micro-turbine. The compact unit transfers heat from the turbine’s exhaust to water or glycol.
This provides residents with domestic hot water and radiant heat for the condo’s floors, via fluid circulated through hollow tubes embedded in the concrete floor slabs.
Mariah also built an electronic controls package that automatically transfers power to and from the city’s electrical grid, depending on the condo’s power requirements. Adamson says that through a secure Web site now under construction, “we then can control and operate and monitor all of our machines from a central dispatch, so that we don’t even have to step foot on the site.”
Walker Court’s building shell consists of tightly sealed concrete walls in a styrofoam insulation “sandwich.” Condo units are separated by continuous concrete dividing walls, ensuring sound isolation between neighbouring units and from the outside.
“The whole building is basically an energy storage system,” Adamson explains.
“With all of this mass, once the building is up to temperature, you could just shut your heating system down and cruise for probably 24 hours before you start noticing anything.”
Each of the 12 condo units combines a street-level retail or office space with basement, and a one- or two-level residence above with rooftop garden.
Residents are within minutes of downtown by walking or bicycle, and a few blocks from the Bow River and the Inglewood Bird Sanctuary.
Mariah Energy retains all responsibility for operation and maintenance of the heat and power system. Condo owners simply receive monthly statements indicating the amount of heat and light consumed, along with an estimate of greenhouse gas emissions prevented from going into the atmosphere.
Adamson says the company has ordered another nine Capstone micro-turbines, including a new 60-kilowatt machine available in February, for future projects in Alberta, Ontario and Quebec.
The next project in Calgary is scheduled for next spring at the Roadking large-truck wash just off Peigan Trail. The truck wash will use the turbine-generated heat, while the electricity will be sold to Alberta’s power pool.
Web Watch:
www.mariahpower.com
www.microturbine.com
