Vancouver lays groundwork for carbon-neutral buildings
The City of Vancouver is laying the groundwork to achieve its ambitious goal of requiring all new buildings to be carbon neutral starting in 2020.
Also called net-zero buildings, these structures generate as much energy as they consume, thereby producing no climate-altering greenhouse gasses.
According to David Ramslie, manager of the city’s sustainable-development program, a new building code is coming out next year, one that he described as the first real step toward making residential and commercial constructions carbon neutral in the near future.
“It’s not going to get us all the way there, but it’s going to get us pretty close,” Ramslie told the Georgia Straight in a phone interview. “It’s going to set us up with a lot of tools that we need to do to make the next jump in our building code. By 2020, we’re going to probably issue our final building code, which will be for carbon-neutral buildings. We see probably three big policy and regulatory jumps between now and then.”
The objective of having carbon-neutral buildings is part of Vancouver’s goal to become the greenest city in the world by 2020. According to its action plan, entitled “Vancouver 2020: A Bright Green Future”, the technology already exists for this new construction requirement.
Ramslie pointed to the 64-unit housing development for seniors at Southeast False Creek as the first carbon-neutral building in the city.
Generically called the Net Zero Building, it opened with other social-housing facilities last year. It draws waste heat generated by an adjoining grocery store and harvests the sun’s energy though a solar thermal system. The building’s energy consumption is lower than conventional buildings. This is made possible through design and good insulation.
The building actually sells the excess heat it generates to the city’s Neighbourhood Energy Utility, which supplies hot water and space heating to buildings at Southeast False Creek, according to Ramslie.
He explained that a major component to realizing carbon neutrality in buildings is the reduction of a structure’s energy use by at least 50 percent.
“Creating renewable energy is not an easy thing to do,” Ramslie said. “It’s expensive, and when you look at a building that uses as much energy as it does today, it will be almost impossible but definitely not very economic to produce that much energy on site. But if we were to reduce the total energy use by 50 percent, then we can start to get to a place where renewable energy consumption can perhaps meet the needs of the building.”
That’s a challenge that sustainable-building expert Stephen Pope is familiar with. An architect by training, Pope looks at energy flows as a researcher with Natural Resources Canada.
“The amount of energy you can generate from any one particular place is limited by our conversion technologies right now,” Pope told the Straight by phone from Ottawa. “So for an individual building to be energy neutral in an urban circumstance is very, very difficult. It is easy to put more people on a piece of land than you can generate energy for under our current understanding of what people need. It’s very easy to oversaturate the land and create a larger energy demand than you can satisfy.”
According to Pope, the concept of carbon-neutral buildings is gaining currency because buildings today are extremely wasteful.
In Vancouver, for example, more than 50 percent of the city’s greenhouse-gas emissions are accounted for by heating and the provision of hot water in buildings.
Although Vancouver is targeting the operations of future buildings to be energy neutral, Pope noted that other definitions of this idea include carbon neutrality for materials used in construction.
“So you have to then cover that investment by [energy] savings over the life of the building, and if you’re going to use that full description, you have to sort of amortize that original investment in energy for the materials,” Pope said. “It has to generate more energy than it actually uses to amortize over time that original investment.”
Apr 21, 2011 at 1:48pm
Measuring the energy a building consumes after construction is to be commended however that is only 50% of the issue. What the building is built out of can have a significant carbon positive impact. Unless the city also adopts some sort of Life Cycle Analysis the amount of carbon released by the choice of building materials may make the building carbon positive for decades. Check out the Athene Institute for more information (www.athenasmi.org).