Renewable Energy & Advanced Lighting Systems for Grid-Connected Exterior Applications

Line of trees along the street illuminated by lighting posts

Exterior lighting generally operates from early evening through early morning, a period of little to no renewable energy generation, which means this lighting is primarily powered by carbon-dense fossil fuels. Fossil fuel use is a significant contributor to greenhouse gas emissions (GHG), poor air quality, water pollution and land degradation. In addition, low-quality exterior lighting characterized by poor color, inappropriate light distribution, and inadequate light levels has also been linked to increased crime rates and reduced physical activity within the surrounding community. For many California cities, antiquated electrical infrastructure combined with aging fixtures and sources has created insurmountable maintenance challenges resulting in inoperable luminaires that further exacerbate already poor exterior lighting conditions. Combine these conditions with Public Safety Power Shutoffs (PSPS), which are increasingly common, and you have a carbon-intensive system that disproportionately impacts disadvantaged and low-income communities already suffering from an unsafe exterior environment with substandard lighting.

To address these issues, the California Energy Commission funded CLTC to develop and demonstrate renewable energy and advanced lighting (REAL) systems equipped with many of the advanced features absent from today's commercial exterior lighting systems. These features include hybrid power (solar and grid-tied); battery energy storage (BES); control systems equipped with two-way communication between the grid/utility and the lighting network for real-time updates (i.e. time-of-use, PSPS, etc.); best-in-class energy-efficiency; predictive and adaptive occupancy-based dimming; and use of circadian-appropriate lighting spectrum. REAL systems will be designed specifically to have hybrid power, smart controllers for best battery charging time, light and health, reduced carbon emissions, reliability and community safety.

Importantly, this project re-invents lighting design practices specifically for low-income and disadvantaged communities by engaging residents and business owners directly in a series of local community studies and technology demonstrations. Only by pursuing this inclusive, community-focused relighting strategy can the true potential of energy-efficient, demand-flexible, exterior lighting for improved safety and health be realized.  CLTC will collaborate with its industry partners and committed demonstration communities to ensure REAL systems meet community technical and cost effectiveness needs, including:

  • Reduced energy use of up to 80% compared to each community’s baseline;
  • Stored solar electricity in an integrated battery that can power the luminaires at night;
  • Integrated adaptive, networked controls to enable grid flexibility capabilities that maximize the use of low-or-no carbon electricity sources;
  • Occupancy and schedule-based dimming;
  • Interconnection with utility to participate in net energy metering or similar utility programs, where available;
  • Safety and security, glare reduction, enhanced visibility and safety for drivers and pedestrians; and
  • Potential for deployment of REAL systems in other communities after the project concludes.

Project duration: July 2021 to March 2025
Project funding: $4,166,306

Project Type