MAKING THE MOST
OF YOUR ENERGY DOLLARS

In this section, we describe cost-effective energy conservation measures that go beyond behavioral changes, but that do not entail full system conversions. Instead, these strategies require a modest amount of capital and typically yield a quick payback.

MANY SCHOOLS SEE THE LIGHT

Lighting is often the easiest and most cost-effective retrofit measure that a school or other facility can undertake. According to the U.S. Environmental Protection Agency (EPA),
approximately 25 to 30 percent of a building's energy bill is for lighting. In addition, lighting upgrades are considered low-risk and typically have a 25 percent (four-year) rate of return. Finally, these retrofits usually have other benefits. For example, EPAsays efficient lights generally reduce maintenance costs (because high-efficiency bulbs tend to last longer) and enhance the atmosphere by improving the quality of illumination and the well-being of the occupants (by reducing glare, for example).

Schools that want to upgrade their lighting have two basic options: they can "relamp" with high performance lighting fixtures or they can install solar lights.

REVAMPING LAMPING

The simplest way to upgrade a facility's artifical lighting system is to replace incandescent light bulbs with compact fluorescents (CFLs). According to the Department of Energy's National Renewable Energy Laboratory, CFLs give off the same amount of light as incandescents but cut energy use by 60 to 75 percent. They also last about 10 times longer.

Many schools are also starting to use controls such as photocells, timers and occupancy sensors which turn off lights automatically when a room is not being used.

CASE STUDY:
RETROFIT REDUCES UTILITY BILLS
AND VANDALISM

A $12 million district-wide lighting retrofit at the San Diego Unified School District was so successful it recently won a Certificate of Merit in the 1996 Energy User News Efficient Building Awards Competition.

The retrofit of 1,600 buildings reduced annual energy use 30 percent while increasing average light levels from 25 to 40 footcandles. The project entailed replacing T12 lamps with T8s, switching from magnetic to electronic ballasts, replacing
approximately 15,000 lighting fixtures with compact
fluorescents, and installing occupancy sensors. The sensors have had the unexpected benefit of decreasing vandalism, since the lights switch on when people walk into a room.

The net cost of $9.1 million has been financed through a municipal bond offer. The local utility, San Diego Gas and Electric (SDGE), helped coordinate the retrofit and provided a $2.9 million rebate. SDGE has calculated annual energy cost savings from the project at about $2.5 million, resulting in a three-and-a-half-year payback. District officials expect the project to reduce maintenance costs as well.

For More Information: J. William Naish, Utility and Energy Coordinator, San Diego City Schools, Maintenance and Operations Center, 4860 Ruffner St., San Diego, CA 92111;
(619) 627-7217; Fax: (619) 279-3582; E-mail: william_naish@smtpgw.sdcs.k12.ca.us.

SOLAR LIGHTING

Solar lighting systems take advantage of the sun's rays to illuminate the inside of buildings. In addition to reducing artificial lighting costs and attendant heat loads, a growing number of schools are learning that natural lighting can also cause students to do better in school. (See p.12). Most solar lighting systems are modern versions of the skylight. The
roof-mounted units are built around a high-tensile strength,
leak-proof frame and retainer which admit sunlight into a building and transmit it as far as 12 feet via a reflective light shaft. The light is then sent into an interior diffusing lens that spreads the light evenly over the space below.

In passive systems, direct, as well as ambient, sunlight strikes an impact-resistant acrylic dome. Active units have an additional feature that tracks the sun with mirrors. This allows greater amounts of sunlight to be captured when the sun is at low angles - in the early morning and late in the afternoon. The tracking mirror also enables active solar lights to diffuse sunlight into the building more uniformly. (Schools should check with solar lighting experts about which system is most appropriate for their facilities.)

According to solar lighting companies, solar lights have the following advantages over electrical lights:

• they can lower electric lighting costs by up to 90 percent (depending on geographic location);
• they do not radiate excess heat (as incandescent lights typically do), thereby reducing heat loads on
  air-conditioning systems;
• they are not vulnerable to power outages;
• they are non-polluting; and
• they cost virtually nothing to operate, after the initial purchase, and are nearly maintenance-free.

CASE STUDY:
PASSIVE SOLAR LIGHTS A BRIGHT IDEA

The Kyrene School District in Tempe, AZ has installed over 2,600 passive solar lighting units since 1992. These units, which cost approximately $700 each, were installed in 14 schools. While 400 of the units were installed in existing buildings, most of the 2,200 units were installed during construction of new schools. The total investment of approximately $1.8 million was made from the District's bond funds. Annual electric savings are projected to be approximately $130,000, yielding a payback of 14 years.

Passive solar lighting systems were selected instead of active systems because the District decided the additional tracking feature was unnecessary - more than 90 percent of the days in Kyrene are sunny and the school is operated primarily during the peak sunlit hours of the day.

The school's equipment was designed, manufactured and installed by the Natural Lighting Company. The company has demonstrated that other, less sunny, areas can also benefit from solar indoor lights. For example, the company installed five passive solar lighting units in an elementary school in Reston, Virginia, which it estimates will enable the school's library to turn off its electrical lights about 65 percent of the time. The school's principal, Linda Goldberg says, "the library transformed into a beautiful and inviting environment when the solar lights were put in and we hope to install more units in conjunction with future renovation projects."

For More Information: Mike Hilgers, Director of Construction, Kyrene School District, 8700 South Kyrene Rd., Tempe, AZ 85284; (602) 496-4648; Fax: (602) 496-4829. Kory Schuknect, Natural Lighting Co, Inc., 7021 W. Augusta Ave., Suite 106, Glendale, AZ 85303; (602) 435-6542; Fax: (602) 939-0677. Linda Goldberg, Principal, Hunters Woods Elementary School, 2401 Colts Neck Rd., Reston, VA 22091; (703) 860-1030.

SCHOOLS BUNDLE UP FOR THE WINTER

Schools can inexpensively construct and renovate buildings to yield a lifetime of energy saving by utilizing two low-cost technologies: insulation and energy-efficient windows.

Insulation installed around walls, ceilings, floors and foundations keeps heat from escaping in winter and coming in during summer. Half or more of an ordinary home's heat loss is through exterior walls, floors and roofs, according to the Rocky Mountain Institute's Homemade Money.

Even more effective are new window technologies such as low-emissivity coatings. These coatings, which transmit light but not heat, perform better as energy savers than insulated walls, according to the DOE's Lawrence Berkeley Laboratory (LBL). LBL found low-emissivity windows can save more than half of the energy lost through older windows. For assistance, call the U.S. EPA Energy Star Buildings hotline ((888) STAR-YES) or see its Website at http://www.epa.gov/energystar.html. Information is also available from the National Fenestration Rating Council, which evaluates the performance of windows, doors and other fenestration products ((301) 589-NFRC).

EPA GIVES SCHOOL
LIGHTING PROJECTS
A "GREEN LIGHT"

In return, Green Lights Partners are asked to sign a voluntary, non-regulatory Memorandum of Understanding (MOU) with EPA in which they agree to survey all of their facility space and undertake retrofits which promise to save money and "do not compromise lighting quality." All participating schools have five years to complete "profitable" upgrades - those with an estimated rate of return of 20 percent.

For More Information:Green Lights Program, U.S. Environmental Protection Agency, 6202J, Washington, DC 20460; (202) 775-6650; Fax: (202) 775-6680; Web: http://www.epa.gov/docs/GCDOAR/EnergyStar.html.