LED traffic signal modules as an incandescent lamp alternative

Institute of Transportation Engineers. ITE Journal, Apr 2003 by Iwasaki, Randell H

An interesting note to this final chapter in the Caltrans LED program occurred in early 2001. In most freemarket environments, unit prices increase when there is product scarcity. What happened in the case of LEDs truly demonstrated the power of government to transform a marketplace.

According to discussions with LED suppliers, an estimated 600,000 LED modules had been installed worldwide from the early 1990s until 2000. With the marketplace incentives from California utilities and CEC, coupled with the increasing cost of electricity, Caltrans was considering installing up to 170,000 modules and other cities within the state were planning purchases that easily could have topped 400,000 units. In early 2001, LEDs (the individual parts, not the complete modules) were in short supply. If the LED market had been mature, conditions would have dictated an increase in LED unit prices.

However, the LED market was not mature. Manufacturers were not producing but they had the ability and infrastructure to significantly increase production without new capital investments. The LED manufacturers stepped in and demonstrated both the power of their newly expanded production capacity and their desire to support the birth of a major new industry in the world. Their prices were lower. Within a three-year period, 12-inch red balls decreased from $180 each to the mid- to low-$60s. When bids were opened in January 2001, every color and configuration of LED fixture came in far under previous unit prices. More recent purchases have shown more price reductions. The same 12-inch red balls are now less than $50 and the price of the green modules is even more astounding at less than $100 per unit.

The power of mass procurement coupled with the lure of the California customer marketplace brought a young industry into full maturity.

CONCLUSIONS

While Caltrans' major procurement and implementation effort is nearly complete, new construction and future replacements will continue to influence the department's effort to improve the product and find new ways to apply cost-effective emerging technologies.

This effort is the result of a team of players from government, utilities, universities, manufacturers and even critics. The result is a high-quality, cost-effective product that improves the reliability of the safety systems in place along the state's roadways.

Primary Benefits

* Reduced energy consumption (up to 85 percent with all LED modules)

* Reduced maintenance activities (re-lamp cycles increased to five years for red modules and 10 years for others)

* Increased reliability ("burn-out" repairs reduced up to 90 percent, less overtime and lower chance of an indication failing)

* Ability to use battery backup systems economically (a battery backup system to run an all-LED intersection for two to four hours costs $3,000 installed)

Secondary Benefits

* Caltrans has had an influence on the LED market. Over the past few years, Caltrans has purchased as many as 30 million individual LEDs. Because of the price reductions, the high brightness LEDs that are used in traffic signals now are economic alternatives in other areas. At the same time, Caltrans has seen improvements in technology. LED efficacy is improving as progress is made in the materials, adding to greater energy savings and improved performance as LED manufacturers try to expand and compete in the LED market.