The DoE's Energy Star proposal seeks a 2009, 2012, 2015 rollout. But a more realistic timetable may keep participants in the program who might otherwise drop out if the proposed, more onerous schedule is adopted.A two-stage phase-in with Stage One implemented one year after the program parameters are finalized (mid-2009); and Stage Two implemented in 2014.
U-factor and SHGC values be brought in line with aggressive goals as predicted by industry experts as attainable within six or seven years.
U-factor is heat flow (like R-values in insulation). SHGC is solar heat gain. Low SHGC means reflecting off energy and using less energy for air conditioning -- important in the South. High SHGC values are better in the North, where you want to absorb heat from the sun. Anyway, the Department of Energy is pushing standards so high that they would require a "triple glazing" approach. That would mean product redesigns for thicker windows. The AAMA wants to delay the adoption of those higher standards so that "compliance can be gained in a way that does not require a dramatic redesign of products" -- and to let the technology improve. In a few years, researchers may well find a way to hit the same efficiency values with a "double glazing" approach.
Alternate compliance paths coupled with realistic program parameters that maintain a consistent and clear message to the consumer via the Energy Star label.
This is a suggestion to recognize that window performance is more than just a specific particular combination of particular U-factor and SHGC values, and that other equally efficient products could have other values, such as a lower SHGC to compensate for a higher U-factor.
Careful cost-benefit or payback analysis that evaluates decreasing demand for more expensive products, while accounting for price elasticity.
Some AAMA members say that the new requirements will raise the cost to make products. Will that make consumers less likely to buy? What's the consequence of decreasing the amount of Energy Star product in the market if the price goes out of reach?
Closer alignment of the five Energy Star zones with those provided in the IECC climate zone map, and redefinition of the Northern Zone parameters.
Best way to explain this is with maps. First, here is the proposed Energy Star climate zone map:
Next, here is the IECC's climate zone map of the United States:
Note the area circled by the AAMA in red -- the association suggests another look at parts of Idaho and eastern Oregon and Washington.
Well, I hope that gives a better picture of the factors in play with these proposed Energy Star window ratings. Many thanks to the AAMA's John Lewis for the clarifications.
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