When undertaking a lighting renovation in a Federal building, daylighting is the primary renewable energy opportunity. Photovoltaics (PV) also present an excellent opportunity. While this guide focuses on the renewable energy opportunities, energy efficiency may also present amble opportunity for energy and cost savings.
Renewable Energy Options for Lighting
Daylighting maximizes the use of natural light in a space to reduce the need for artificial lighting. Incorporating daylighting into a lighting strategy should occur during the planning stage of design since it affects all aspects.
Ambient light dimming controls are critical in daylighting, since the energy savings are realized by dimming artificial lights when enough natural light is available. Proper daylighting design involves more than lights and controls, though, and design elements, such as light shelves, can be used to limit the direct sun and glare into a space or to transmit natural light further into a space. Skylights can be used to bring more natural light into a space.
If a lighting renovation does not incorporate daylighting, new lighting design controls should be adequate to accommodate ambient light dimming. Omitting this capacity can block future opportunities for energy savings.
Although not every renovated space will have adequate natural light available to achieve a fully realized daylighting design, most spaces can benefit from incorporating it into the design. This is especially true of renovations that include not only lighting but also interior, building envelope, and roof renovations. Special attention should also be paid to the operations and maintenance plan for the daylighting. Ensuring the building operators understand the controls can reduce the likelihood of alterations that could reduce savings.
An additional renewable energy consideration in lighting design can arise when the existing space has too many windows. When glare or overheating are issues, some of these issues may be resolved with daylighting design, such as light shelves, but shading may also warrant consideration. In these cases, shade structures outside windows, such as awnings, present an excellent opportunity and location for solar electric or PV modules. In addition, some newer technologies provide a light tube with integrated photovoltaics to power LED lights so that the tube provides some limited light after dark.
Beyond renewable energy, lighting renovations present a range of opportunities for energy savings through energy efficiency design. The Federal Energy Management Program provides details on a range of energy-efficient lighting technologies. Additional resources and information on energy-efficiency lighting can be found in the Whole Building Design Guide.