Solar Signs Making Appearance

Flashing, solar-powered devices can be seen two miles away.

By John Andrew Prime - Jul. 19, 2007

This solar-powered, illuminated stop sign is one of many
cropping up in northwest Louisiana and other parts of the
country. They can be seen up to two miles away at night
and can catch your eye even in the daylight. (John
Andrew Prime/The Times) BlinkerSign® from TAPCO

This solar-powered, illuminated stop sign is one of any cropping up in northwest Louisiana and other parts of the country. They can be seen up to two miles away at night and can catch your eye even in the daylight.

The next time your passenger asks you if you saw the blinking sign, it may not be a criticism of your driving.

New solar-powered traffic signs are cropping up in dimly lighted rural areas and places where traffic engineers want to grab drivers' attention.

"The state uses them, parishes use them and cities use them," said Keith Tindell, an engineer with the Louisiana Department of Transportation and Development in Bossier City.

Tindell said he first noticed the signs in Waskom, Texas. "I came across this flashing sign at night and said 'What's that?' I came back in the daytime and checked it out."

You use them when and where you really want people to see this sign."

Tindell contacted his counterpart with the Texas Department of Transportation and Development, Carlos Ibarra, and was steered to the Wisconsin company TAPCO, which makes the environmentally friendly traffic controls.

"We put our first two in at Kickapoo, at (U.S.) Highway 171 and state Highway 5," Tindell said.

The signs have low-voltage but powerful LEDs that can be seen up to two miles away and don't require being wired into a system, as overhead flashing caution lights would. That means expensive power lines, which can also constitute a hazard in case of wrecks and flooding, don't have to be installed. And it means the signs can be easily relocated as traffic needs dictate.

"They're specialized," Tindell said. "You use them when and where you really want people to see this sign."

An example of rural use in Caddo Parish is at Wallace Lake at Flournoy-Lucas roads, where four command the attention of drivers coming from each point on the compass.

Examples of use in Shreveport include crosswalks near public libraries, such as at Shreve Memorial's Cedar Grove branch, warning drivers on busy Line Avenue of crosswalk traffic.

Michael Erlund, Shreveport traffic engineer, said only a handful of the signs are in use in the city: at about six pedestrian crossings and about half as many stop signs. They were installed about 18 months ago, he said.

One sign has been stolen, but Erlund is pretty sure it was so damaged in the removal that the thief gained nothing.

Even at $1,500, the signs are a 10th of what it costs to install an overhead light, he said. "I see some increasing use but, then again, that expense is considerable.

"So when we install them, we're looking at locations that have a specific need that can't be addressed by anything else."

And familiarity breeds contempt, especially on streets and highways.

"If you overuse them, people think 'well, that's just a blinking sign' and they don't see it," Erlund said. "We want to use them where there's a real, obvious reason."