June 2009 Archives

Waste heat to warm buildings

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This example of using the waste heat from a data centre to warm nearby building is a good illustration of the potential to be realized by linking energy flows across several buildings:

Any laptop user will know that even the most casual of Twittering with a computer resting on your knees can get uncomfortably hot — so imagine the vast amount of heat that a massive IT data centre kicks out. Now telecommunications company Telehouse Europe is planning to capture that and pipe it to nearby homes and businesses.

(Via Worldchanging.)

Passive house details

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The 100K House project has started building a passive house in Philadelphia, and they are doing a bang-up job of sharing the construction details. Their first article on their passive house goes into detail on the laying of the foundation, with thermal bridging eliminated by encapsulating the concrete slab with rigid XPS insulation:

Our Passive House consultants from PHIUS (Passive House Institute of the US) gave us the following basic design rules for our foundation and slab insulation:

  1. Under slab insulation of R-50 (10″ of XPS Rigid insulation)
  2. Outer foundation wall insulation of R-10 (2″ of XPS Rigid insulation)
  3. Separation of the floating slab from all foundation walls with a minimum of 1″ (R-5) of rigid XPS Insulation

Passive House Foundation Detail

In their second article on passive house construction they discuss under slab air-sealing:

We get asked a lot what the biggest difference is between the 100K House project and the Passive Project. The answer is always the same. Air Sealing.

On a Passive House, we have to hit a very strict target on our blower door test of 0.6 Air Changes per Hour at 50 Pascals of pressure. This is no easy task. Every single seam must be caulked, or preferably taped, to hit this target. That all starts with the foundation. We’ll review a couple of the key details for the foundation air sealing below.

Air-sealing under the foundation seems a bit extreme to me, but maybe they have some concerns about cracking.

Passive House Foundation Detail

An article in the Guardian discusses the potential for rapid real-time adjustments in demand for electricity to compensate for fluctuations in electricity supplied by wind and solar power. On the face of it, this sounds like a recipe for brown outs. Enter the humble water heater:

Dr Barrett says the [water] heaters could be switched on and off rapidly to compensate for the erratic output of wind turbines and solar panels, each heater controlled by a gadget that responds to signals sent through the electricity grid – a system used since the second world war. “Everybody is always looking for a shiny new silver-bullet solution” says Dr Barrett, “but this idea is cheap, safe, and based on technology that’s been around for decades”.

He says it is vital the new “smart meters” the government plans to install in every home by 2020 should be capable of controlling hot-water storage. “But this isn’t rocket science,” says Dr Barrett. “It is quite clear we can go hell for leather installing renewables because we can deal with intermittency using heat storage.”

From crisis to hope

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I spent last week (June 11, 12) at the Canadian Green Building Council’s (CaGBC’s) second annual summit, Every Building Can Be Green. It was a fantastic conference with expert speakers from a range of disciplines talking about everything from sustainable community development to building performance simulation. I’d like to briefly summarize on this site, over the next week or so, what I saw as the highlights among the sessions I attended.

The conference opened on Wednesday morning with a sobering keynote from Thomas Homer-Dixon, a well known scholar at the University of Waterloo whose research is focussed on how societies adapt to rapid and complex changes in technology, in economics, and in our environment. Homer-Dixon’s keynote started with an overview of the many challenges posed by rapid climate change. In summary, the latest evidence shows that we are in very deep trouble. Unprecedented changes in our climate will rapidly accelerate in the coming years; positive feedbacks which amplify climate change are outweighing negative feedbacks that might dampen it (Arctic sea ice is disappearing 30-50 years faster than even the worst-case climate models have predicted); heat waves and drought will place enormous pressure on global food supplies; and the nonlinearity of the climate system means that the climate could rapidly swing to a new, less hospitable, equilibrium from which it may not be able to return. Recent research suggests that carbon dioxide can stay in the atmosphere for a very long time, and that slowing and stopping climate change requires us to get to zero carbon emissions as quickly as possible. Homer-Dixon summed up the first two thirds of his talk with a cartoon reading simply “We’re fucked”. It was meant as a joke, and like a lot of good jokes, it was probably funny because it had the ring of truth.

After this depressing beginning, Thomas Homer-Dixon started to slowly bring us back up. He expressed the hope that this crisis will create opportunities for the deep changes in behaviour, in institutions, and in our cultures that are needed. He pointed to coping strategies, such as efficiency, conservation, large-scale development of renewable energy, carbon-capture and sequestration, nuclear energy and, in the longer term, geo-engineering, and atmospheric carbon capture. Although I might quibble with the need for more nuclear energy, what I found particularly interesting in this last phase of his talk was Homer-Dixon’s emphasis on the need for new economic models which are not based on relentless, rapacious growth. He pointed out that economic growth has been a useful tool in reducing friction between rich and poor, and that a new economic model will require us to develop a more equitable planet. He further argued that we need to design our technological and social institutions with greater resiliency by loosening couplings, increasing redundancy and diversity, decentralizing, and maximizing flexibility. By moving more to the local, but not too much.

There was a part of me that felt discouraged and disheartened after listening to Thomas Homer-Dixon’s talk, but what I came away feeling was the “fierce urgency of now”. His address crystallized the urgency of what we are doing, of the absolute need for us to stop overloading the world and to start regenerating it. Every building must be green.

Great news from the New York Times Green Inc. Blog:

Renewable sources accounted for 56 percent of investment dollars, worth $140 billion, while investment in fossil fuel technologies was $110 billion, the U.N. program said in a report, Global Trends in Sustainable Energy Investment 2009, released on Wednesday and produced in collaboration with New Energy Finance, a research company based in London.

(Via Worldchanging.)

Concentrated solar power

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Gristmill has a link to an announcement that Lockheed-Martin will be joining the solar game by building a large concentrated solar power plant with thermal storage in Arizona:

What is the best evidence that concentrated solar thermal power (CSP) aka solar baseload is indeed a core climate solution with big near-term — and very big medium-term — promise?  One of the country’s biggest companies, Lockheed-Martin, with 2008 sales of $42.7 billion, has jumped into the race to build the biggest CSP plant with thermal storage.

Gardens in the sky

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There’s something truly wonderful about how green building is encouraging people to bring life—in all of its wonderful diversity—back into cities. From the New York Times:

Aeries are cropping up on America’s skylines, filled with the promise of juicy tomatoes, tiny Alpine strawberries and the heady perfume of basil and lavender. High above the noise and grime of urban streets, gardeners are raising fruits and vegetables. Some are simply finding the joys of backyard gardens several stories up, others are doing it for the environment and some because they know local food sells well.

City dwellers have long cultivated pots of tomatoes on top of their buildings. But farming in the sky is a fairly recent development in the green roof movement, in which owners have been encouraged to replace blacktop with plants, often just carpets of succulents, to cut down on storm runoff, insulate buildings and moderate urban heat.

From the New York Times:

The world’s largest for-hire chip maker could soon start manufacturing solar cells and LED lights. The company’s entry into these nascent industries will catch the attention of existing makers, which could find themselves battling one of the most formidable manufacturers on the planet. Taiwan Semiconductor could drive down prices, as it did for computer chips. But the lower prices could also stimulate demand for what are now expensive technologies.

Great news from Treehugger:

Roofs make up 21% of the area of Toronto, so it is logical that they should be put to good use. Now they will be green; by a stunning 36-2 vote, council approved new rules that require green roofs on residential buildings next year and on industrial buildings in two years.

SAB Magazine has announced the 2009 winners of its Canadian Green Building Awards:

  1. Community Center Pointe-Valaine in Otterburn Park, Quebec, Smith Vigeant Architectes, Montreal
  2. Artscape Wychwood Barns multi-purpose public space in renovated Toronto street car sheds, du Toit Architects Limited, Toronto
  3. Triffo Hall, renovated heritage building at the University of Alberta, Group2 Architecture Engineering Ltd., Edmonton
  4. Dockside Green - Synergy, Phase 1 of a sustainably-designed community in Victoria, Busby Perkins+Will, Vancouver
  5. Vancouver Aquarium Discovery Education Centre, Stantec Architecture, Vancouver
  6. Crawford Bay Elementary and Secondary School, Crawford Bay, BC, KMBR Architects Planners Inc., Vancouver

The winning projects will be widely shared in a special issue of the July/August SABMag and website, www.sabmagazine.com, through the media, and in speaking engagements throughout the year.

100,000 on The Hill

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350.org shares the announcement of a campaign to spur the Canadian government to take serious action on climate change:

100,000 on The Hill is a convergence of our concern. We want to show our government that we demand strong climate policy and we expect proper representation and cooperation at the Copenhagen Climate Conference. On October 24th, 2009, 100,000 Canadians in person and signature will make the trek to Parliament Hill in solidarity with people around the world who want to rewrite the story of climate change.

Wonderful news from the Canadian Green Building Council:

Leading up to its 2nd Annual National Green Building Summit in Montreal on June 9 to 11, the Canada Green Building Council (CaGBC) announced today that the 100th building and the first two homes have become LEED® Canada certified.

Let’s hope growth is exponential from here.

Green roofs in winter

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I’ve been looking for information on green roofs in Ottawa and came across this interesting article on the benefits of green roofs in winter:

Their research showed that winter green roofs could reduce the energy used for heating by more than 10 per cent during the cold season in the test house that is used as the National Research Council of Canada’s field roofing facility in Ottawa.

It turns out that a combination of added insulation from the porous soil medium, and protection from the wind offered by small juniper shrubs was able to partially shield the roof from the extremes of Ottawa’s cold winter weather.