Solar power lights up East Grand Forks bike path
 |
Solar-powered streetlights were the most cost-effective way to light a bike path that runs along the flood plain of the Red and Red Lake rivers in East Grand Forks, Minn. In case of emergency, qualified city workers can remove the lights without the help of a line crew. (photo courtesy of East Grand Forks, Minn.)
|
Cyclists taking an evening ride along the Greenway Project bike path in East Grand Forks, Minn., might notice something unusual about the lighting—that is, if they haven't already heard about the city's experiment with solar-powered street lights.
That would be unlikely, since the municipal utility expended a lot of effort to install the 19 lights and wants to share its experience with others interested in problem-solving applications of the green power source. "It was a bit of an experiment, and there was a learning curve," admitted General Manager Dan Boyce.
Although the lights have only been fully operational since May 2003, Boyce said that the city would definitely consider using solar energy in other situations where it offered a cost-effective alternative to conventional power.
Conventional lines cost, risk make solar attractive option
The location of the Greenway Project bike path presented exactly that type of situation. The path route runs for 4,800 feet along the Red and Red Lake rivers, a wonderful place to walk or ride on a sunny day. However, it was the site of a devastating flood in 1997. The money used to build the bike path was part of a $2 million grant from the Minnesota Department of Transportation to repair and rehabilitate the utility's system and build a permanent levee against future flooding.
The city wanted to light the path so residents could get the most use from it, but the requirements for stringing electrical line in the flood plain are stringent. Between lines and labor, the installation would run into tens of thousands of dollars, and East Grand Forks would have to self-insure the lines.
After all that expense and risk, traditional hardwired lights would be at the mercy of the weather. Debris swept along by even a minor flood can cause serious damage to stationery streetlights and power lines. In a serious flood, a city line crew would have to remove the lights. "In an emergency, line crews have better things to do, believe me," Boyce declared.
Those challenges alone were enough to make East Grand Forks look at alternative ways to light the bike path. The municipal utility saw some opportunities, as well. "We had been advocating the use of alternative lighting. The bike path gave us a low-risk setting to put it into action," explained Boyce. "It also helps us fulfill some of our renewable requirements."
Research, communication, second try make new technology work
The decision made, the footwork began. The utility contacted Western for information about PV applications and surfed the Internet for engineers, proven products and similar projects. "I exchanged e-mails with people all over the country including Washington State," Boyce said, referring to concerns about whether a solar project could work so far north.
The plans for the path lighting were only a small portion of the entire reconstruction project. "We drew them up more than two years before installation," Boyce recalled. "At that point, we were still learning which questions to ask."
The experience taught the city that good internal discussions are essential when adopting a new technology. The original units designed by Solar Outdoor Lighting, Inc. used 80-watt, flat-mounted collector panels that stored only enough energy to run the lights for five hours, and then only in the summer months. "If we want our ratepayers to support green power sources, we have to show them that they are not losing any service and wherever possible, getting better service," Boyce said.
Determined to make the streetlights work, engineers added a second battery and a bracket to tilt the array at a 45-degree angle facing directly south. The lights now burn six hours per night year around, more than enough time in the summer when the sun sets as late as 10 p.m., and even enough to light the way for cross-country skiers in the winter. As an added bonus, if river waters rise, qualified city workers can move the lights, freeing line workers for more pressing duties.
Ultimately, the decision was driven by the bottom line. "This is always a high priority for small utilities," Boyce said. "The bike path was a niche application where the alternative happened to be the most cost-effective solution."
The general manager went on to recommend that solar options be considered wherever there is an on-going cost. He added that he has been impressed by the number and ingenuity of solar applications. "The technology has matured in the short time since we installed our lights. There's a lot more products and information out there now."
Better yet, for those new to green power, there are people like Boyce who believe in sharing their stories.
