Solar Technology
Although I agree with the basic premise of the column "Who Will Be Held Liable for Green Designs?" by Stephen J. Vamosi, PE (Engineering Green Buildings, December 2010)—that much caution needs to be exercised to avoid becoming swept up in the marketing frenzy popularly called "LEED"—Mr. Vamosi appears to commit the very same sins of overstatement he cautions against.
For instance, Mr. Vamosi writes, "Anyone taking the time to investigate the technology behind solar energy would have discovered a solar, or Trombe, wall would not rise above 60˚F to 62˚F." Hundreds of peer-reviewed technical papers published in scholarly journals indicate otherwise.
Mr. Vamosi claims some solar installations failed because they were "in climates that experienced average winter solar days of 10 to 20 percent." If he is referring to the typical "percent possible sunshine" data published by the National Oceanic and Atmospheric Administration (NOAA) and the National Climatic Data Center (http://bit.ly/9zKGof), no city in the United States, including Anchorage, Alaska, has levels of sunshine that low.
It appears Mr. Vamosi suffered some kind of solar-energy-related trauma that left him so scarred he feels the need to disparage the rapid advances in solar technology made over the last 30 years as a "debacle." During the learning-curve period with any emerging technology, there will be many project failures and mistakes (and not a few charlatans). Dismissing the solar technology developed during the 1980s as a "fad" does nothing to enhance the credibility of Mr. Vamosi's message.
Carl Mezoff, AIA, PE
Stamford, Conn.
Author's response:
My statement about the Trombe wall not being energy-efficient is based on my own research. During the 1980s, I measured the internal temperatures of a Trombe wall (12-in. concrete block, with cavities filled with concrete) for a full winter. Sunny-side temperatures were above 100°F during the day and dropped below 20°F at night, while inside temperatures fluctuated around 62°F, with a maximum deviation of ±2°F. While I realize my statement goes against everything published and taught about the Trombe wall, one just needs to sit back and analyze the thermodynamics of the wall: The hottest surface faces the (cold) outside, while the inside surface temperature holds practically steady at the median temperature. The gravity heat circulation is minimal; the nighttime heat loss is significant. It was not an accident that Trombe-wall installations were involved in several lawsuits. Today, I am not aware of a single new installation.
Mr. Mezoff's reference to the NOAA data is correct. I was referring to solar installations in Canada that were abandoned within a few years because of insufficient solar income.
Regarding my "solar-energy-related trauma": I have designed several successful solar homes without Trombe walls. I believe in solar technology probably as much as Mr. Mezoff does. I referred to the solar-construction boom of the 1980s to demonstrate what happens to a useful technology when the "charlatans" take over.
For the record, I am not against the green movement. I just do not like the businesslike approach of LEED.
Stephen J. Vamosi, PE
Intertech Design Services
Cincinnati, Ohio
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