Why We're Testing
Following the direction of Mayor Chris Coleman and his desire for city departments to embrace "green" practices in the delivery of city services, the Traffic & Lighting Division of Saint Paul Public Works is currently testing new street lights designed to last longer and use less energy. This division operates and maintains 37,000 light fixtures and 32,000 street light poles, so using energy efficient street lamps that last longer can dramatically reduce the public costs for electricity and maintenance.
We currently use three main types of lights: lantern style, globe style decorative lighting and cobra-head highway-style lighting. At present these fixtures are equipped with High Pressure Sodium (HPS) bulbs.
Technology in the lighting industry is continually evolving. Given the promise of reduced costs that flows from changes in the industry, we believe we have an obligation to the public to examine new products as they emerge.
Types of Lighting Being Tested
LEDs (light-emitting diodes) have been around since the 1960s. You've probably seen them used as indicator lights in consumer products. Over the past few years, we have replaced our traffic signal incandescent lamps with LED lamps, resulting in significant energy savings. Although they cost more upfront than the bulbs they replace, LED lights use less energy and last longer than conventional bulbs, which could result in savings on energy and maintenance costs. Other advantages of LED’s is that they produce directional light, which give us more control over what we light, produce a whiter type of light, and contain no hazardous materials.
Lighting induction lamps are high frequency (HF) light sources, which follow the same basic principles of converting electrical power into visible radiation as conventional fluorescent lamps. The life of induction lamps on the market today reaches 100,000 hours. This makes it beneficial to use such lamps in applications where lamp maintenance is expensive. Other advantages of induction lighting are they are capable of producing a wide range of color temperatures and they maintain lumen (light) output over their life.
We are working with various manufacturers to develop, install and test energy efficient Street Lighting. The testing will examine energy consumption, ease and cost of retrofit, illumination levels, and community acceptance. One critical question to be answered is whether energy efficient street lighting produces light levels which meet our current light level standards in St. Paul.
Let Us Hear From You. . .
Although scientific tests are important in the decision-making process, public reaction will also help to guide our decisions. Please share your comments with us by e-mail at:
Where We're Testing:
ORNAMENTAL LANTERN STYLE STREET LIGHTING:
Iowa Avenue between Lexington and Dale
We are testing both LED fixtures from various manufacturers on Iowa Avenue. These lamps are typically 40 watt to 50 watt replacing our standard 70 watt HPS lamps in our city standard Arlington Style Lantern Street Lights.
GLOBE STYLE STREET LIGHTING LED RETROFIT
The City of Saint Paul was the recipient of a $330,000 grant from the American Recovery and Reinvestment Act (ARRA) Energy Efficiency and Conservation Block Grant (EECBG) Funds. The funding was used to convert over 880 High Pressure Sodium Globe Lights to energy efficient LED Fixtures.
The City of Saint Paul was also the recipient of a State of Minnesota, Office of Energy Security Grant for $120,000. The grant funding along with the local match was used to convert an additional 700 of the City’s Globe style light fixtures from High Pressure Sodium Lamps to energy efficient LED Fixtures.
The LED conversion was completed in April 2011 and can be seen around the downtown area in such areas as:
• Wabasha Street
• Rice Park
• John Ireland Boulevard between Kellogg and 12th Street
• St. Peter Street
• Cedar Street between 11th Street and 12th Street
• Minnesota Street between 11th Street and 12th Street
• Robert Street between 11th Street and 12th Street
• Jackson Street between 11th Street and 12th Street
• Robert Street between Kellogg Boulevard and Fillmore Avenue
• Kellogg Boulevard between John Ireland Boulevard and 7th Street
The retrofit will save approximately $30,000 per year in Energy Costs and reduce Carbon Dioxide Emissions by 255 metric tons or the equivalent of savings of CO2 emissions from 28,600 gallons of gasoline consumed.
ROADWAY COBRAHEAD STYLE STREET LIGHTING
Maryland between Earl and east of Frank
We installed 128 Watt LED cobrahead type fixtures to replace 250W HPS cobrahead style fixtures on six street lights on Maryland Avenue from Earl to east of Frank.
Thomas between Mackubin and Arundel
We installed 76 Watt LED cobrahead retrofit kits to replace 150 HPS cobrahead style lamps on four street lights on Thomas between Mackubin and Arundel.
Warner Road and Shepard Road
Existing High Pressure Sodium (HPS) cobra head style fixtures were replaced with LED cobra head fixtures.
In conjunction with the mill and overlay of Snelling and the Bus Rapid Transit project we are installing LED cobra head fixtures as well as Lantern Style fixtures.
LED LANTERN STYLE STREET LIGHT INSTALLATIONS
LED Lantern Style Street Lights are being installed as part of our Street Restoration Projects throughout the City. 50 Watt LED lanterns are now being installed rather than 70 Watt HPS lanterns. This provides a substantial reduction in electrical consumption and the promise of reduced maintenance.