A few weeks ago, Brute Force attended the CascadiaGBC Transformational Lecture with Thomas Auer of Transsolar Energietechnik. While we were disappointed that such a minute crowd showed up (there were maybe 20 people in the auditorium), those that made the effort were treated to a phenomenal lecture. We’ve discussed the work of Transsolar in previous posts, and have been impressed with their work for several years. Transsolar is on the forefront of thermally activated building systems, an area we will definitely be discussing at a later date. One of the projects that Thomas presented, which has seen quite a bit of press, is the 22-story Kuwabara Payne McKenna Blumberg-designed Manitoba Hydro Place in Winnipeg (CA).
Integrated Design Process
Unsurprisingly, Manitoba Hydro followed an Integrated Design Process – since I was working abroad instead of taking professional development courses in school, the process is familiar, but the term is somewhat new. IDP allows for synergies to be played up, systems to be downsized and costs to be streamlined in a coherent manner. At Brute Force, we have always felt that bringing in engineers in the early design phase to play an active role makes a lot of sense. In our professional life, we’ve worked in similar modes as the IDP, but never to the extent that this team did. Manitoba Hydro and KPMB have even set up a website documenting their Integrated Design Process, it is an insanely phenomenal resource. We realize it’s not easy but it would be outstanding if most major projects could have equally informative documentation.
KPMB and Transsolar went through several iterations of solar, massing and wind modeling – resulting in a handful of optimized schemes. One of the moves KPMB enacted was locating the offices along the interior, allowing maximum daylight within the building. Floor plates are also significantly narrower than most North American towers. This is something we ran across over and over again while working in Europe, although in the U.S., many companies refuse to make this simple move. Allowing workers access to daylight and views while keeping energy costs down just makes a lot of sense. Unfortunately, at a previous corporate gig, Brute Force was actually reprimanded and called a socialist for doing just this. And so it goes…
The site is located in the heart of Winnipeg, and was seen as a re-engagement with downtown. A cafeteria was not added, allowing a number of the 2,000 employees to help revitalize local shops. The site was selected due to proximity to public transportation.
We were surprised to learn that while Winnipeg has some of the largest temperature swings, it also has significantly more winter sunlight than most Canadian cities. These extremes became an asset, and Transsolar really pushed to utilize this solar gain effectively.
Manitoba Hydro utilizes a number of techniques we have discusses on previous posts, and a number of the strategies towards energy reduction are similar to the kybernetik prinzip. The building utilizes a wintergarden, luftkollektor, thermally coupled mass and has a compact form.
The south façade includes three stacked six-story wintergardens (atria), utilized for pre-heating cooled air in winter, and pre-cooling warm air in summer. Waterfalls at each wintergarden are used to humidify winter air with warm water or dehumidify summer air with cold water. Fans from each wintergarden pull the pre-conditioned air into the raised floor at the work spaces. In summer, blinds can be positioned to reduce solar exposure.
The luftkollektor is a glazed twin-wall incorporating manually operated interior windows and BMS-operated exterior windows. Blinds within the airspace cut down on solar gain and glare.
Thermally coupled mass
The building incorporates concrete slabs that are activated w/ hydronic loops to heat and cool office spaces.
To the north is a solar chimney, which is glazed at the upper portion to increase airflow. Displacement ventilation allows all air to be drawn fresh from the exterior.
Solar Thermal Storage
A topic we’re really fond of, Manitoba Hydro has 280 boreholes of 6” diameter drilled to 400’ below grade. In summer, the building is cooled by extracting heat from the building (via tubing in the exposed concrete slabs) and charging (superheating) the borehole field. This process is reversed in winter, providing nearly 60% of the required heating.
Additional ‘green’ details
A detail we really like but rarely see, the slab edge is raked to provide more daylight into the interior. This also becomes a space for storage of large shades.
A green roof never hurts, since it mitigates the heat-island effect, provides natural habitat and looks a hell of a lot better than modified bitumen or gravel.
Manitoba Hydro Place was designed to achieve a maximum of 140kWh/m²a – which would put it close to achieving Passivhaus Standard for primary energy (120kWh/m²a). While fully glazed buildings can often be terribly inefficient and incur huge losses of energy, Transsolar and KPMB have come together and created an efficient and attractive solution that works on every level – in fact, this may be one of the most progressive and incredible projects we’ve seen in Canada (or North America) for a while. It is great that these concepts are being successfully incorporated on this side of the Atlantic, and we’re definitely looking forward to the future work of both Transsolar and KPMB.
architect: Kuwabara Payne McKenna Blumberg
architect of record: Smith Carter Architects
mechanical: Earth Tech
structural: Crosier Kilgour + Partners, Ltd.
energy consultant: Transsolar Energietechnik
construction cost: ca. $260,000,000 (CA$278,000,000)
GFA: 695,750 sf
cost/sf: $373/sf (for reference, the NBBJ-designed WaMu tower was about $300/sf)
- Smith Carter’s case study presentation of Manitoba Hydro Place (PDF)
- Passive and low energy architecture 2009 paper on Manitoba Hydro Place (PDF)
- Transsolar write up on Manitoba Hydro (PDF)
- betterbricks Integrated Design Process checklist (PDF)
- Canadianarchitect.com March 2010 writeup