Solar Lighting: Making Steps Off-Grid towards a Sustainable Future
Learning Objectives - After this course, you should be able to:
- Explain the benefits of using solar-powered lighting.
- Identify the components of an off-grid solar luminaire.
- Discuss how to choose a light source/luminaire.
- Describe how systems are sized to meet clients' needs.
- Assess which applications are best suited for off-grid solar lighting.
Providing sustainable, energy-efficient lighting systems, while maintaining performance and aesthetically pleasing forms, is sure to be one of the greatest challenges for architects and design professionals in the 21st century.
Â Global attention to climate change and environmental disasters, such as "The Gulf Oil Spill," has intensified the spotlight on environmentally conscious design and the use of renewable energies. According to the U.S. Department of Energy (DOE), residential and commercial buildings consume more than one third of the energy used in the United States each year. Lighting for commercial buildings accounts for 25 percent of this energy usage. LEED, ASHRAE/IESNA 90.1 and California Title 24 have helped drive design professionals to respond with innovative solutions to achieve their design intent. Manufacturers are challenged with providing energy-efficient and environmentally friendly products to meet market demands while evaluating their own carbon footprint in the process.
Photovoltaics (PV) is a solar energy technology that uses semi-conductors to directly convert solar radiation to electricity. Charge controlled stand-alone PV exterior lighting systems will be discussed to provide the knowledge needed to successfully specify and apply this new technology.
Benefits of Using Solar-Powered Lighting
Cost savings. The decreasing cost of PV modules and increasing costs of electricity only strengthen the existing benefits of using solar-powered lighting. Possibly the greatest benefit of solar lightng is the ability of the system to operate without the presence of an electrical infrastructure. As the distance from a project site to a source of electricity increases, the time it will take to pay off a solar-powered lighting system will decrease. In addition to eliminating the need to trench, backfill and route conduit and wire, electrical distribution equipment such as transformers, circuit breakers and controls are no longer needed, and therefore a solar lighting system requires less man hours to install compared to traditional lighting systems. Not having to verify underground utilities, obtain electrical permits or schedule electrical inspections simplifies project coordination. Along with the above mentioned cost savings, an owner or municipality will not pay an electricity bill for the life of the system.
Solar lighting extends usability of a popular bike path in Madison, WI.
Photo: SELUX Corp.