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Photo of an employee replacing light bulbs.

The County's recently completed lighting retrofit saves more than 3 million kilowatt hours and more than $350,000 taxpayer dollars per year.


Switching to more energy-efficient lighting is a great example of a win-win, saving money while reducing greenhouse gases. In 2009, advances in lighting technology offered enough energy and life-cycle cost savings to inspire the County to complete its second large-scale lighting retrofit in 15 years. The retrofit included 26,000 fixtures in over 3 million square feet at 52 county owned & leased buildings.

How We Did It

  • Completed an energy audit of our buildings and determined that installing energy efficient lighting could provide a significant savings and pay for itself in less than 4 years.
  • Secured $250,000 in incentives and obtained a low interest loan (3.95%) from the California Energy Commission. Each building pays a portion of the debt service, which is more than made up for by the energy costs they save. No upfront capital was needed.
  • Worked with a lighting contractor to pilot and select the appropriate technology for our needs, acquire the materials, and perform the installation in stages with minimal disruption to our workforce.
  • Replaced older technology T-8 fluorescent lamps with long-lasting, low-mercury, 5,000 Kelvin T-8 lamps and retrofitted electronic ballasts to third generation technology. High intensity discharge (HID) lighting fixtures were replaced with new T-8 lamps and fixtures.


In some cases, employees complained that the lighting was too bright. The solution was easy. We just removed a lamp from those fixtures, saving even more energy.


The new lighting:

  • Gives off a wider spectrum of light which is whiter and closer to daylight.
  • Uses 30% less electricity and lasts 6,000 hours longer than older lighting, reducing the labor needed to maintain lighting.
  • Reduced mercury in County buildings by 350,000 milligrams by specifying low-mercury lamps.


  • Reduces energy use by nearly 3 million kilowatt hours per year.
  • Reduces our carbon footprint by 1.6 million pounds annually.