Top Ten Underused Technologies for Saving Energy

The following article is reprinted from the City of Jackson Questline Newsletter.

 Key Points

• The U.S. Department of Energy has identified promising, but underused energy-saving technologies.
• These technologies have been ranked by their potential to save energy.
• The top 10 include lighting, heating and air conditioning and building envelope technologies.

      Source: www.nist.gov

Energy-efficient technologies cannot save energy if they are not used. The U.S. Department of Energy (DOE) has identified promising, but under-utilized technologies and ranked them by their potential to save energy. The top 10 of these are listed below. By implementing some or all of these technologies, you can follow the example of the most innovative facilities and save on your energy costs.

1. Low ambient/task lighting. By lowering ambient (overhead) light levels and only providing task lighting where it is needed, you can reduce lighting energy use by 15 to 25 percent. Task lighting controls provide the potential for more savings.
2. Condensing boilers. Natural gas-fired boilers equipped with enhanced heat exchangers that extract more heat energy from exhaust gases have improved combustion efficiency by more than 10 percent. These boilers work well with hot water systems that operate at lower temperatures. Installation at a U.S. Marine Corps facility improved average thermal efficiency from 69 to 79 percent and reduced annual natural gas consumption for space heating by up to 13 percent.
3. Super T8 lighting. Features of these 32-watt lamps include a barrier-coat design, high lumen maintenance, long service life and high light output. Replacing a regular T8 and ballast with a Super T8 and low-factor ballast combination can result in energy savings of 15 to 20 percent. Super T8s can be integrated with other fluorescent lighting-based measures, such as low ambient/task lighting, delamping configurations and daylighting controls.
4. Commercial ground-source heat pumps. Ground-source heat pumps use the constant temperature of the earth to provide efficient heating and cooling. Water is pumped through tubing buried in the ground or submerged in water. The water releases heat in the summer and absorbs heat in the winter. Because ground source systems move heat rather than create it, they have efficiencies much higher than 100 percent. Ground-source heat pumps have the potential to reduce energy use for cooling by 30 to 50 percent and for heating by 20 to 40 percent.
5. High R-value windows. R value measures the thermal resistance of windows; the higher the R value, the lower the heat loss. These high-performance windows have an R-value of 5 (compared to R-2 for conventional windows) and features such as triple panes, spectrally selective coatings and thermal breaks. R-5 windows reduce heat loss significantly compared to conventional models, which saves money by lowering the heating load. At the same time, spectrally selective coatings reduce solar heat gain, lowering cooling costs.

Source: www.energy.gov

6. Duct sealants. Aerosol-suspended sealants reduce leaks in ductwork. This technology works well with variable-air volume (VAV) systems because these ventilation systems can rebalance automatically. When applied in a number of U.S. Navy facilities, heating, ventilating and air conditioning (HVAC) savings ranged from 7 to 50 percent, with simple paybacks of 6 to 11 years.
7. Interior LED lighting. Down lights, under cabinet lighting and task lighting are suitable indoor applications for light-emitting diode (LED) retrofits. LEDs are becoming more cost competitive with fluorescent lamps and have better dimming characteristics.
8. Exterior LED lighting. Improved directionality, better cold-weather performance and long life are just a few of the many benefits of light-emitting diode (LED) technology for outdoor lighting. After retrofitting to LED parking lot lights, a U.S. Navy facility reduced power by 50 percent, while increasing light levels by 20 percent.
9. Computer power management. Network-based software manages computer power consumption by automatically putting them in standby, hibernation or other low energy-consuming states without interfering with user productivity. A facility with 50,000 client computers implemented this technology and achieved a 40 percent reduction in energy costs, which translates into $1.8 million per year.
10. Spectrally enhanced lighting. DOE studies show a 20 to 45 percent reduction in energy use with the same level of occupant satisfaction. Energy savings are achieved by using fewer lamps, lower ballast-factor ballasts and dimming. Light levels can be reduced with the same visual acuity.

The DOE has identified many other technologies for lowering energy costs, such as condensing water heaters, integrated daylighting systems and cool roofs. Details on these and other technologies can be found on the DOE's Federal Energy Management Program website.