Last year, when Jonathan Smith was still the president of Earth911.com, a Web site dedicated to recycling, he said he would often board a plane after a speaking engagement or a day of meetings with a dead cellphone in hand.
With limited recharging options available, “it was really frustrating,” he said. “Having access to a working port or finding an open plug during layovers at the airport was just too unpredictable.”
Hoping to solve his problem, Mr. Smith bought a portable solar charger he could prop up in the window of a plane. “I’d plug it into my phone and when we landed, I was ready to go again.” The charger meshed well with his environmental values, of course. Still, “when I first started using solar to charge my devices,” he said, “it was out of convenience.”
In fact, Mr. Smith is one of a growing number of business travelers who, out of practicality or concern for the environment, use portable renewable energy devices — primarily portable solar panels, but also hand-cranked electricity generators known as dynamos or freeplay devices — to power up their electronics when they work in places that offer little or no access to electricity.
“Basically, this technology makes our work possible,” said John Poulsen, a tropical ecologist who investigates logging’s effects on animal populations in the forests of central Africa. Often, data collection takes Mr. Poulsen as much as 25 miles from the nearest road. “The research we do requires being in the forest for two to three weeks at a time. And if we had to go back to the village every two or three days for batteries, we just couldn’t do it,” he said.
Generally speaking, portable renewable energy devices cannot power large equipment, like desktop computers or printers. But they can generate enough electricity to operate laptops, satellite telephones, movie and still cameras, sound-recording equipment, GPS equipment and camp lighting, said Stuart Cody, owner of Automated Media Systems in Allston, Mass. The company customizes portable solar arrays and battery backup systems for business travelers and adventurers.
The devices have improved significantly since they were first introduced in the mid-1990s. That was about the time the tree kangaroo conservation program, administered by the Woodland Park Zoo in Seattle, began using portable solar power at its field sites in Papua New Guinea. “Initially, we got panels that didn’t work very well,” said Lisa Dabek, the zoo’s director of field conservation. Now, the solar panels used to power laptops, navigation devices and satellite phones “are much smaller and much more portable,” she added.
The organization uses this technology for reasons that have as much to do with practicality as with environmental concerns. Fuel-powered generators, Ms. Dabek said, are “very heavy. And to hike uphill with them for two days is not really an option.” Moreover, generators “make a lot of noise that would scare away the tree kangaroos.”
Mr. Cody said users should be realistic about how much power portable solar panels could create.
“People who are starting from scratch don’t realize that solar panels don’t always put out a consistent stream of energy,” he said. “The sun comes and goes. There’s a shadow that reduces the current flow.” As a result, Mr. Cody suggested using the devices to charge internal or external batteries, rather than to run electronics directly. “Here’s an analogy,” he said, likening a battery to a water storage tank. “You have a little water pump pumping a small, constant stream of water in a tank. Without that tank, you couldn’t have a shower.”
The occasional intermittence of these devices’ energy supply can be a drawback. But for some users, they are literally lifesavers. “We have lions and elephants nearby here,” said Martin J. Graber, a doctor and international development consultant who works in the Narok district of southwest Kenya. Dr. Graber uses a solar-powered lantern when he goes to the outhouse at night. “I want to make sure there are no animals.”
Dr. Graber said he also used the lanterns in the clinics he helped to develop. “We have a new clinic that has no electricity at present,” he said recently. “There was a young man who came in who had a finger almost entirely amputated. We used the light from the lantern to take care of his finger.”
Mr. Smith, who is now chief executive of Blue Legacy International, an environmental nonprofit group that develops Web films to “focus attention on water issues around the world,” used his portable charger in July to power his Twitter posts when he and a colleague became stranded in the middle of Tonle Sap lake in Cambodia, one of the world’s largest bodies of fresh water. Because Mr. Smith had a solar charger, “we were able to get someone to send us another boat,” he said. “And we were able to save a day of filming.”
Taking these devices on airplanes poses no difficulties, a spokeswoman for the Transportation Security Administration, Lara Uselding, said in an e-mail message. The only exceptions are larger storage batteries that contain “liquid coolant, lubricants, etc.,” she said. They fall under the hazardous materials designation and are not allowed on planes. (Those batteries should be shipped as hazardous materials.)
“I’ve never had any trouble going through airport security with these chargers,” said Mr. Smith, adding that security personnel were often intrigued by the devices.
“When you find these devices that are innovative and socially responsible,” he said, “it’s fantastic.” Business travelers who work in remote locations “have this very real necessity that’s solved by these renewable devices, and it enables us to practice what we preach.”