Tempe City Council approved more than $800,000 in federal stimulus money in October to fund the replacement of high-pressure sodium streetlights with induction lights, which are cost-effective and reduce energy use and greenhouse gas emissions. The year-long project is set to begin the third week of December, according to Amanda Nelson, spokeswoman for Tempe.

The induction bulbs are expected to use between 30 and 50 percent less energy than the current sodium streetlights. The lower end of that estimate is figured for residential areas while the higher end is anticipated downtown, according to research from the city's Public Works, Finance and Technology and Community Development departments.

The city predicts lower maintenance costs due to the lifespan of the induction lamps (20-plus years) compared to the current streetlights (three years). The induction lights have around one-tenth the mercury that the sodium lights do and are easier to recycle.

Induction lights emit a white light instead of the yellow cast of the sodium lamps. The brighter light allows for greater visibility for residents on roads and sidewalks. Tempe also hopes it will aid in solving crimes, as witnesses and victims could potentially better identify and describe details of incidents.

The fixtures that will support the induction bulbs are compliant with guidelines from the International Dark Sky Association, an organization dedicated to reducing light pollution (artificial light that obscures the sky). The fixtures are designed to direct light downward and avoid uplight. The new lights have about half the wattage of the current lights and give off less reflective glare.The funding comes through the American Recovery and Reinvestment Act. The city received money from two grants - the Energy Efficiency and Conservation Block Grant Program ($377,000) and the Community Development Block Grant Recovery funds ($432,500) administered through the U.S. Department of Housing and Urban Development."City staff conducted the research, looking at lighting programs in other cities, as well as researching a variety of lighting options and gathering/analyzing data from our own lighting installations," Nelson said in an email.

The new lights are planned for north and central Tempe as well as downtown, but officials are seeking to expand the project city-wide.