Windows that are more energy-efficient than insulated walls. Washing machines that use a minimal amount of water. Thermostats that control ventilation and humidity as well as temperature.
These are just a few of the energy-efficient innovations manufacturers are currently testing and hoping to introduce within the next few years.
Some, such as fluorescent lamps which can be dimmed like incandescent bulbs, improve upon existing technologies. Others, like smart windows that control light and heat penetration, are brand new products.
But either way, they are moving rapidly from laboratories to the marketplace.
Here, courtesy of Merrilee Harrigan, a senior program manager at the Alliance to Save Energy, a nonprofit organization dedicated to promoting the more efficient use of energy, is a rundown of the new generation of products coming soon to a builder, remodeler or store near you:
– Windows. An estimated 40 percent of today’s residential windows contain a low-emissivity coating or other advanced glazing that significantly reduces heat loss through the glass and dramatically increases efficiency.
In some regions of the country, in fact, windows are tailored to their specific climate. For example, in the South, where summer heat gain can have a greater impact on space conditioning than winter heat loss, windows are available with special coatings to block more of the unwanted gain.
Because cooling loads are less, homes with these windows can get by with smaller air conditioners, and the money saved by switching from larger units helps offset the higher cost of the windows.
The next step beyond selective glazings is switchable window coatings which alter their properties according to the weather. Electrochromic glazings are now being developed with a multilayer coating that changes color and light transmission qualities when a small electric charge is passed through it.
During a cool but sunny spring morning, for instance, a south window might be transparent to light and heat. But in the sunny afternoon when the temperature outside rises to 85 degrees, the window can be directed, either manually or by an electronic sensor, to change its properties to reflect light and heat.
These windows will be on the market within two to four years.
– Appliances. Dishwashers are already on the market that sense how dirty the dishes are and adjust their cycles accordingly. And microwave clothes dryers that use 25 percent less electricity than conventional hot-air dryers and are kinder to fabrics are now being field tested. If they prove viable, they could be in stores in two or three years.
Right behind them are horizontal-axis washing machines that use less water and detergent and also are said to be easier on fabrics. Instead of being constantly immersed in a drum full of water, clothes are circulated through a smaller amount of water. The machines also are designed to spin faster, extracting more water so that even less energy is required for drying.
– Controls. Unified temperature and indoor air-quality controls look like regular thermostats and perform all the functions of programmable controls, but they also manage ventilation and humidity, among other options.
Instead of using the thermostat’s reading as the reference point for determining the entire home’s temperature, for example, such a system would use indoor sensors to determine the average temperature in various rooms, or use a particular room as the reference point for setting heating and cooling levels. And outdoor sensors would tell owners when it’s time to clean or change their furnace filters.
– Lighting. Smaller compact fluorescent lamps that fit most fixtures designed for incandescent bulbs are now on the market. And control units that allow CFLs to be dimmed are expected to be on retailers shelves early next year.
– Insulation. Fiberglass is now available in compressed “super batts” that don’t require thicker wall or ceiling cavities. This is particularly useful in cathedral ceilings, where 2-by-12 joists are now required to accommodate a fiberglass batt with an insulation value of R-38.
New products are being developed that use vacuum evacuated panels to achieve higher R-values in refrigerator doors and water heater shells, making these appliances less expensive to operate. Prototypes have achieved an R-value of 75 per inch, with an inch-thick, 5-by-5-foot panel having an R-value of 35.
– Heating and cooling. Geothermal ground-source heat pumps use the earth’s relatively constant temperature to supply heating, cooling and sometimes even water heating.
Also available are gas-driven heat pumps. Their cooling efficiency is comparable to a conventional air-to-air heat pump, but their heating efficiency is even greater. Like geothermal heat pumps, though, their initial cost is high, but their operating costs are lower.
The scourge of even the most efficient HVAC system is leaky ducts. But a new process is under development that is expected to cut by half the cost of sealing ductwork, an extremely labor-intensive affair.
The system pressurizes the ducts and sprays in an aerosol sealer, which closes cracks and holes as it passes through them.
