Ashrae Journal - December 2008 - (Page 60) Building America By Joseph W. Lstiburek, Ph.D., P.Eng., Fellow ASHRAE Y ou have to love salesmen. They figure out solutions long before physicists, usually before engineers, and certainly before greenies. Harry Tschumi and Les Blades,* a pair of salesmen from Arkansas, figured out in the 1960s that increasing insulation levels and improving window performance meant that you could sell heat pumps that actually worked in houses. They found that heat pumps didn’t work in houses with lousy building enclosures. Why? The heat pumps cost too much to install and too much to run because they had to be sized big to compensate for the lousy building enclosure. It’s not that they didn’t work technically. It’s that they didn’t work economically. Tschumi and Blades found, what we all should know, that it is much more cost effective to fix the enclosure. That way the system that is actually needed is small, saving on installation and operating costs. By the way, this approach also saves energy. Who knew? Apparently, the lesson still has not caught on. How else to explain the silliness with geothermal and photovoltaic panels? Architects love geothermal (next to PV). It is the technology du jour. However, what I see is another gadget to bolt on to a building that should have never been built in the first place. It’s more technology to attempt to justify poor enclosure design and poor architecture. In my experience every dollar spent on conservation technologies saves two or more dollars on sexy equipment such as geothermal. In fact, I’ve come to the conclusion that we can save enough energy with conservation, so that the PV rarely makes sense†—except as a social statement. This is OK by me, because I love to make social statements. But, at least I know when they are social statements. I also don’t try to get the taxpayers to subsidize my social statements. Conservation should not be news. This was all figured out long before by some smart folks, some of who are still alive, who are still smart, but mostly bemused at what passes for green today. Let me first define what green should be focused on if I was in charge: 80% energy, 20% everything else, such as water and materials. The new “golden mean” of 80:20 will achieve perfect harmony and proportion for buildings and the built environment.‡ If you want to design a green building program or a green building, this is what your priorities should be. The single most important aspect of green should be energy. OK, I feel better now that I’ve once again pointed out the obvious. Let’s move on and become reacquainted with those smart old folks I mentioned. One of those smart old folks was Wayne Schick§ at the University of Illinois at Urbana-Champaign. He pushed the Tschumi-Blades revelation to a whole different level with the “Lo-Cal” House in 1976. “Lo-Cal” stood for low calorie. Mr. Schick did a computational study of how much energy you could save with high levels of thermal insulation, airtight construction and heat recovery ventilation using air-to-air heat exchangers.1 The Lo-Cal House sure got attention. The insulation values Schick proposed were R-60 ceilings, R-30 walls and R-20 crawlspace floors. Folks said no way. Then a bunch of Canadians—Dave Eyre, Bob Besant, Rob Dumont and Harold Orr all out in Saskatchewan (Canada’s flyover province)—built the Saskatchewan Conservation House in Regina in 1977,2,3 and the “no way” became history. The house had R-60 ceilings, R-44 walls (12 in. [305 mm] thick, double-wall construction) and R-20 shutters over standard double glazed windows. It was also ultratight and featured an air-to-air heat exchanger for ventilation.# “Build tight, ventilate right was born.”** *Mr. Tschumi sold heat pumps, and Mr. Blades worked for Arkansas Power and Light selling electricity. Their radical ideas somehow came to the attention of Frank Holtzclaw of the U.S. Department of Housing and Urban Development (HUD) who initiated the “Arkansas Project” in 1974 that led to the construction of dozens of houses with 6 in. walls insulated with R-19 insulation and raised heel trusses that came to be known as “Arkansas trusses.” So the next time you get annoyed at HUD, or the next time you want to laugh at the folks in fly over Arkansas, tip your hat to Tschumi, Blades and Holtzclaw for doing something unbelievably innovative and special, nurturing the beginnings of energy conservation in the United States before the first energy crisis. †For PV to make financial sense the cost of acquiring it and installing it must drop in half and the cost of energy must double. For those of you who can follow this higher math, this is a factor of four. PV currently costs around $10/W, and electricity is around $0.15/kW. I don’t see PV dropping to $5/W. I also don’t see electricity going to $0.60/kW except under peaking conditions. Maybe some combination of the two with time-of-use billing to capture the peak conditions would work. But, until this happens keep your powder dry, invest in the building, i.e., conservation, and then the building will be ready, if and when PV makes sense. To put conservation into perspective, we can get to two-thirds of architect Edward Mazria’s zero carbon building goal just with conservation. The Westford House gets us there, and so do other buildings. That last third is the PV domain, and we might not need to get it if we get everything else. ‡Before you can have a “green” building, you need a building first. This building needs to be able to stand up, not be blown away in a hurricane, not fall down in an earthquake, not burn, not leak rainwater, not be moldy, not rot, not corrode and otherwise be able to meet applicable building codes such as having a basic provision for ventilation like that specified by Standard 62.1. This is the starting point for the 80:20 “golden mean.” No points for IAQ, comfort, and durability since they should already be part of the basic building. The “everything else” comes after the basic building requirements are met. To me, that principally means water conservation and materials. §Schick is credited with coining the term “superinsulation.” But, lots of folks in Alaska say Axel Carleson from the University of Alaska and a guy by the name of Richard Bentley got there first. The U.S. Patent Office seems to think so as well. Bentley’s patent in 1976 for a double-wall house talks about airtightness and air-to-air heat exchangers. This will take some beers with Bill Rose to sort out. About 100 Lo-Cal houses were ultimately built, many by Harry Hart in Virginia. 60 ASHRAE Journal ashrae.org December 2008 http://www.ashrae.org
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