Monday, June 6, 2011

How Cool is the Centre for Green Cities?

In a previous post I shared with you some of the great features of the LEED Platinum certified Centre for Green Cities building at the Evergreen Brick Works. It turns out this place is even cooler than I thought - pun absolutely intended.

Just as the heat and humidity took over from the cold and rain last week, Evergreen kick started their state-of-the-art cooling system. Using six different but interrelated strategies, traditional air conditioning use will be minimized and energy will be saved.

Keeping the Heat Out
Not only are the building's external walls well insulated, but the windows themselves keep heat out with a special film that redirects heat away from our offices like a mirror. Additionally, all windows are equipped with blinds - sometimes the simplest strategies are the best!

Natural Cooling - Open Windows
In the spring and fall, and on cooler summer days, tenants can open their windows (the type you crank open with a hinge at the top so that a slot opens at the bottom). In the past we've had our office door slam shut because of the cross ventilation from our windows to those on the opposite side of the building. Clearly the windows have been strategically placed to encourage a breeze to run through the building. Ceiling fans enhance this air movement on non-windy days.

Thermal (Solar) Chimneys
Imagine a fire place with the fire at the top: making use of convection, three chimneys run from the second to fifth floors, heated at the top by the sun to draw the building's warm air up and out. Solar-powered fans are used on days when the conditions aren't right for the natural convection process to occur. Brilliant.

Night Cooling - Closed Windows
On cool evenings and nights, the windows are opened and fans are used to cool the concrete slabs that form the building's floors. The next day, with the windows closed again, hot outside temperatures take longer to heat up the building because it was pre-cooled overnight.

High-Efficiency Scroll Chillers
As a last resort, a very efficient staged mechanical air conditioning system can be used at partial or full capacity on the hottest days when the other methods just don't cut it.

Building Control System
An automated system has been programmed to respond to a variety of scenarios based on outdoor air temperatures. The simulation model used to design the system has predicted an energy savings of 30-40% over conventional buildings!

We must collectively begin to recognize that insisting on feeling cool on the hottest summer days is absolutely unsustainable. It is possible to be productive at work while saving energy. I used to hate having to change into pants, closed shoes, and a sweater at my desk at the hospital because the A/C was so cold! A moderate temperature is much more comfortable when you're dressed in shorts or a skirt and a loose-fitting top. Enjoying a Mega Mr. Freeze works, too.

What are ideal working conditions for you? Do you need cold, dry air to be productive at work?

Photo of air conditioners used under Creative Commons from Peter Morgan (pmorgan/flickr).
Photo of Mega Mr. Freeze used under Creative Commons from Christa (Christaface/flickr).


  1. I need to have windows that open. I can't stand A/C blasting when its gorgeous outside. What a "cool" system the Centre for Green Cities has!

  2. I'm not a huge fan of A/C most of the time either, although I tend to be more temperature-insensitive than most... hot weather doesn't bother me as much, nor particularly cool weather.

    That being stated, I do like a nice fan... but ceiling fans seem to be out of vogue these days, sadly!

  3. Lori - I know exactly what you mean. A/C initially feels nice if it's unbearably sticky outside, but eventually it's just cold and unpleasant, and I find myself longing for the sunny warmth outside.

  4. Marc - You're lucky to be temperature-insensitive. I spend 90% of my day feeling either too hot or too cold!

    I'm sure there are modern, trendy-looking ceiling fans on the market these days that would please even the most ardent anti-fan people out there. :)

  5. I have been opting out of the AC in the car this year, just roll down the windows! I also hate the too cold feeling when it is hot outside. I don't have AC in my house - don't need it!

  6. Sherry - I'm so happy to hear you're going A/C-free in your car and home! You know, I heard once that it's actually more fuel-efficient to roll down the windows than to use A/C, even though open windows negatively affects the car's aerodynamics.

  7. Oh yeah, they proved that on Mythbusters once... put the same amount of gas in two identical cars with full tanks of gas and drove around a racetrack until they both ran out of gas.

    I love Mythbusters sometimes!

  8. Thanks for the link to the video! The Mythbusters crew isn't always as rigorous with their methods as I'd like, but I trust their results anyway!

  9. Andrea!

    Love this - great to hear about Evergreen's Building first hand. We up here in Ottawa volunteering with Transition Town loved that Evergreen converted the Brick Works - so wish there was an organization like that up here!

  10. I'm sure there will be in the future. Evergreen celebrated their 20th anniversary this year. They started out small - I'm sure any number of today's little organizations will be tomorrow's key players in the environmental field!

  11. I'm commenting late, but I think this whole air conditioning thing is so important, both at work and at home (and I work from home). So many people are installing a/c now--dealing with extremes of heat by contributing to climate change! We manage by being very systematic about opening windows late evening and early morning, and then closing windows, curtains and blinds during the heat of the day. We use fans for sleeping when it feels unbearable. And although we don't have ceiling fans, we have had them overseas, and I agree it's too bad they aren't more common. After having our roof redone, the new insulation also made a huge difference to the temperatures in our old home. One thing that really bugs me, though, is when I have my windows open on a summer night to make the most of cool air, and must listen to the sound of someone else's a/c! In our neighbourhood, lots of people are not using a/c, but when it happens, it's maddening!

  12. I know, that's quite frustrating. My mom thought her new neighbours were really friendly and nice until they installed their new A/C unit facing her house with not even so much as a bush to muffle some of the sound. We've become accustomed to unrealistically cold air, so these machines end up running 24/7 when they're only really needed in the afternoon. As I've probably said before, one option is to make electricity much more expensive. Then people will turn to better solutions like insulating their homes!