LBNL Report Number
This study describes the impact of lighting management systems that dynamically control lights in accordance with the needs of occupants. Various control strategies are described: scheduling, tuning, lumen depreciation, and daylighting. From initial experimental results, the energy savings provided by each of the above strategies are estimated to be 26, 12, 14, and 15%, respectively.
Based upon a cost of $0.05-0.10 per kWh for electric energy and a 2-, 3-, or 4-yr payback, target costs for a simple and a sophisticated lighting management system are found to be $0.14 and 1.89 per ft2 respectively, for a cost-effective investment.
A growth model, based upon an extrapolation of the increase in building stock since 1975, indicates that the commercial and industrial (C & I) building stock will grow from 40 x 109 ft2 in 1980 to about 67 x 109 ft2 by the year 2000. Even with the use of more efficient lighting components, the energy required for this additional C & I stock will be 307 x 109 kWh compared to the 230 x 109 kWh used today. Adopting controls would reduce this requirement to 243 x109 kWh, an increase of only 13 x 109 kWh above current use.
The specified information is used to analyze the economic impacts that using these systems will have on the lighting industry, end users, utility companies, and the nations economy. A $1-4 x 109 annual lighting control industry can be generated, creating many jobs. The estimated return on investment (ROI) for controls for end users would be between 19 and 38%. Utilities will be able to make smaller additions to capacity and invest less captial at 7-10% ROI. Finally, the annual energy savings, up to $3.4 x 109 for end users and about $5 x 109 for utilities, representing unneeded generating capacity, will be available to capitalize other areas of our economy.