Energy Solutions

I just spent three days at the American Institute of Architects annual convention in Washington, DC, including a fair amount of time at the massive trade show there. I didn’t make it all the way through the acres of exhibits over the eight hours or so I walked the floor, but I saw some really interesting products. I’m highlighting here a few of the windows and glazingWhen referring to windows or doors, the transparent or translucent layer that transmits light. High-performance glazing may include multiple layers of glass or plastic, low-e coatings, and low-conductivity gas fill.-related products I found.

Last week I laid out some arguments on why we should wean ourselves from fossil fuels, and offered some suggestions of how we could go about doing that in our homes — by superinsulating, switching to oil- and gas-free heating, and converting to renewable electricity. Those steps certainly aren’t easy or inexpensive, but there’s a pretty clear path for doing so.

There are a lot of things not to like about fossil fuels. Most obviously, the burning of oil, natural gas, propane, and coal releases huge quantities of carbon dioxide into the atmosphere, where it traps heat through the greenhouse effect.

Last week, I reflected on Earth Day and how concern for the environment inspired me in school and then led to my focus on renewable energy starting in the mid-1970s. This brought me to Brattleboro in 1980 to work for the Northeast Sustainable Energy Association, which I did from 1980 through 1985.

To continue:

With Earth Day this past Sunday, I'm inspired to reflect on what motivated me — some 45 years ago(!) — to focus on a career of environmental protection and improvement, a career that has ledLight-emitting diode. Illumination technology that produces light by running electrical current through a semiconductor diode. LED lamps are much longer lasting and much more energy efficient than incandescent lamps; unlike fluorescent lamps, LED lamps do not contain mercury and can be readily dimmed. me to a significant focus on more sustainable energy solutions. Back in the late 1960s at age 12 or 13, I became immersed in "conservation" and decided that this would be my life career. This was before the modern "environmental" movement really began, and "conservation" was the term used to describe environmental protection.

I've examined state-of-the-art windows and glazingWhen referring to windows or doors, the transparent or translucent layer that transmits light. High-performance glazing may include multiple layers of glass or plastic, low-e coatings, and low-conductivity gas fill. systems over the past four weeks. This week, I'll cover an innovative product that may help define the state-of-the-future: a dynamic glazing called SageGlass that can be tinted on demand. To understand what's so exciting about such a product, let's look at conventional high-performance windows.

Over the last three weeks I've focused on the major strategies for improving the energy performance of windows: adding extra layers of glass, increasing the thickness of the airspace between the layers of glass, adding low-emissivityAmount of heat radiation emitted from a particular body or material. Emissivity is expressed in a fraction or ratio, with the lowest values indicating low emissivity and the highest indicating the high emissivity of flat black surfaces. coatings, and replacing air with a low-conductivity gas fill. These strategies all help to reduce heat flow through an insulating glass unit (IGU), and if we do a really good job with these strategies we can achieve center-of-glass R-values of R-5 or higher.

Over the last two weeks I've covered the major strategies for improving the energy performance of windows: adding extra layers of glass, increasing the thickness of the air space between the layers of glass, and adding low-emissivityAmount of heat radiation emitted from a particular body or material. Emissivity is expressed in a fraction or ratio, with the lowest values indicating low emissivity and the highest indicating the high emissivity of flat black surfaces. coatings. Another important strategy is to use a low-conductivity gas instead of air in the space between the layers of glass. Most commonly argonInert (chemically stable) gas, which, because of its low thermal conductivity, is often used as gas fill between the panes of energy-efficient windows. is used, though kryptonA colorless, odorless inert gas, often used with argon in fluorescent lighting and sometimes used as gas fill in high-performance glazing. is available for the highest-performance windows, and xenon is occasionally used.

Last week I wrote about the early strategies window manufacturers employed to improve energy performance: adding extra layers of glass and increasing the thickness of the airspace between the layers of glass. This week we'll look at a more revolutionary change to window design that appeared in the 1980s: low-emissivityAmount of heat radiation emitted from a particular body or material. Emissivity is expressed in a fraction or ratio, with the lowest values indicating low emissivity and the highest indicating the high emissivity of flat black surfaces. coatings.

I've been working for the past couple weeks on a report on windows — the latest in BuildingGreen's series of special reports on green building (the last one covering insulation). This focus has reminded me just how much we expect of our windows and what an amazing job they do.