Sustainable Institutional Buildings: The New Landscape Architecture Facility T.P. Cathcart P.O. Melby Biological Engineering Landscape Architecture Mississippi State University
Five years in planning, it is the first MSU campus building designed specifically to minimize operational energy use.
After 1 year of monitoring … • Total energy use is 15 kWh / ft2 per year. • By comparison, 2 nearby conventionally designed buildings use 45 and 47 kWh / ft2 per year. • The other buildings use 3 times the energy per unit area as the buildings in the LA facility.
Why Does This Matter? Reason 1: $$$ • MSU spends $700,000 per MONTH on its utility bill. That’s over $8M per year. • If we could trim that bill by 2/3, we would save over $5M each year.
Why Does This Matter? Reason 2: Homeland Security Sustainable buildings are less dependent upon centralized sources of energy. A public building that has minimal HVAC and artificial lighting needs is more likely to maintain function if centralized energy is disrupted.
Why Does This Matter? Reason 3: Sustainability Sustainability – Meeting our needs in ways that allow our children and grandchildren to meet their needs.
Sustainability • Leaving our children a world that is less • inhabitable than the one we were born • into is wrong. • Our descendents have a right to • sufficient resources to meet their • needs. • They have a right to live in a world that • has not been significantly degraded.
We didn’t use to have to worry about sustainability? What has changed? Projected: 9-12 billion by 2050
There are enough of us now to adversely effect the natural systems upon which we depend. • 7000 sq. mile “dead (anoxic) zone” in • the northern Gulf of Mexico. • World wide loss of biodiversity. • Global warming. What is the carrying capacity of earth?
No one knows for sure. But … like a giraffe growing up in a garage, we will eventually have to consider our limits and our options.
So how does a low energy demand building make us more sustainable? • Decreased demand on non-renewable resources. • Decreased pollutant production. • Decreased demand on electrical grid. • Decreased production of greenhouse gases (CO2) • Energy use at an electric power plant is ~3 x’s use at the site. • The LA facility produces 600 Mtons less CO2 per year than a conventionally designed building of the same size..
How did the LA facility happen? Pete Melby & I have been working together for years. Eventually we wrote a book. And the building came out of the book!
Is building sustainably as hard as brain surgery? Answer: No – a lot of sustainable design is just common sense (which we abandoned over the past 50 years or so). There’s no “magic technology” that makes it work. It’s a combination of many small elements, each of which contribute.
Before 1950, many buildings in the South contained techniques that we now call “sustainable.” Before air conditioners and central heat, buildings used passive cooling and heating, and it worked! Passive means that it does not require additional energy. and there were many techniques that were used.
Heat comes from the sun. In the summer, we want to keep it out. Use overhangs that prevent solar radiation from striking the sides of the buildings.
But we know that the elevation of the winter sun at noon is a lot lower than the summer sun at noon ….
Design the overhangs so that direct sunlight does strike the walls (and particularly the windows) in winter.
Then build your floor out of a material that absorbs and can hold a lot of heat. It will heat during the day and … Passive Solar Heating give the heat back at night.
Make the walls thick with stone or brick. The interior temperature will change very little. That’s why caves were such popular dwellings for ancient peoples.
Use high ceilings to keep rooms cool (a good technique for the south, where cooling exceeds heating energy use).
An historical example of use of natural ventilation is between West Point & Columbus: Waverly Mansion
Windows are light years ahead of where they used to be. They were once unstoppable heat leaks. Multi-paned windows using an assortment of coatings and inert gases now have high insulation values.
The current generation of windows use a variety of strategies to reduce heat loss and gain
There are many new insulating materials and places to use them. Shown here is foundation insulation.
Asphalt shingles are the norm for roofing in many places. In the South, they can reach 160 F ! Heat gain through the roof can be more than half of your cooling load.
Reflective roofs are much better in the South. The best and most recently introduced are both reflective and have a high capacity to radiate the heat back into space.
Geothermal (earth linked) Heat Pump. The system used in the LA Facility added $350k to the price of the $4M building. But payback time is ~10 years (much less than expected life).
Air Linked Heat Pump. Air has a relatively low specific heat and a very low density. Not a great heat source or sink.
Geothermal (earth linked) Heat Pump. The earth has a fairly high specific heat and a very large density. It is an excellent heat source and sink.
Photovoltaic system This system was paid for by the Tennessee Valley Authority (part of their green power project). Payback time is ~20 years (about the same as expected life).
MSU has a state of the art example of green architecture. It’s a product of many technologies, some old and some new. It’s also a product of human thought. That’s probably the most important ingredient.
We have lived by the assumption that what was good for us would be good for the world…. We have been wrong. We must change our lives, so that it will be possible to live by the contrary assumption, that what is good for the world will be good for us. And that requires that we make the effort to know the world and learn what is good for it. We must learn to cooperate in its processes, and to yield to its limits. Wendell Berry (“Recollected Essays”)