MU professor builds a solar

Bin Wu, an engineering professor at MU, has only used his car twice in the past four months after putting together a tricycle that runs on solar power.

He calls his solar-powered trike "a horse that doesn't need feeding."

"It's literally and technically true because the motor that I have is 750 watts," Wu said. "That is exactly equivalent to one horsepower."

The design of his tricycle is similar to that of any solar-powered system, using solar panels, an electronic control device, a battery and electricity stored in the battery. In total, it cost Wu $500 to put it together.

All of the supplies were recycled, except the motor, one of the batteries and the charge controller. He said he wanted it to be as environmentally friendly as possible.

"The solar panels are old ones I used to have, and the frame is made of old chairs," Wu said. "The other things like the screws were old, too."

Bin Wu rides his solar-powered tricycle past the MU Columns. He wishes more people knew about the benefits of solar power. "If people paid attention and knew the benefits, it could change the world," Wu said.

When charging with solar, it costs him nothing to "feed the horse," and it needs only a few hours to complete.

"It has 200-watt solar panel on top and two 500-watt-hour lithium batteries," Wu said. "Under the ideal condition, it will take up to about three to four hours to fully charge each battery from completely empty."

With normal maintenance, he expects to use his trike for a long time, depending on the life of the batteries.

"The life cycle of the lithium batteries, according to the manufacturer, is up to 3,000 charge-discharge cycles," Wu said. "Assuming I empty the batteries completely each two days, they should last over 16 years before needing replacement."

The life of the solar panels is another factor, he added, but they normally last at least 10 years.

The design and building process for the trike took a few months, but once it was finished, Wu said he was eager to test it before showing it to his students.

He was delighted to find that it rode with ease, prompting him to test it on the MU campus.

"I just tried it out in the neighborhood, and then tried it on the MKT Trail, and it seemed to be holding," Wu said, "Finally, I decided, that's it, I’m going to take this all the way to the university, which I did."

Bin Wu rides past campus buildings on the Francis Quadrangle. His students at the Engineering School gifted him a horn to attach to the tricycle. "It made my day," he said.

When weather conditions are not favorable, Wu charges his trike using his regular household supply.

"My total battery capacity is one kilowatt-hour," Wu said. "If I plug it in, one kilowatt-hour of electricity costs about, let's say, between 10 cents and 15 cents, allowing me to cover 35 miles."

But the trike can go much longer when the sun is shining. He said the trike usually goes about 15 mph during normal use but can go faster.

"On flat, smooth road, it goes 20 miles per hour maximum," Wu said, "When fully charged, the trike will cover 35 miles on battery power alone. If the sun is out and with a little pedaling, this range is much extended."

When Wu uses his trike to get to campus, it takes him about 25 minutes, which he said is faster than when he drives.

"It takes about 25 minutes door-to-door to cover about 6 miles," Wu said. "This is often less than the time needed if I drive, taking into consideration the traffic conditions, as well as time needed for parking and walking from the parking lot to the office building."

The idea for the trike struck him last fall when he was teaching "Industrial Energy Efficiency and Management," a course he created about industrial energy issues and their environmentally friendly solutions.

The class covered solar energy, he said, which sparked his notion of building a tricycle.

"It occurred to me that instead of just talking about the setup, the theory and the components, it would be nice just to make something like the solar trike and show my students," Wu said.

He added that he likes to consider himself a professor who not only "talks the talk, but walks the walk." It's important to him that his students see how possible it is to make something like his trike a reality, he said.

When his students finally saw the trike, they were eager to give it a try.

"My students really love it," Wu said.

Since that first ride, Wu has been using the trike instead of his car for almost everything, typically shopping, recreation and trips to campus.

"I just jump on it, and I ride on the trail and listen to the birds," he said. "There's no tension, no traffic, no noise. It's very meditative and tranquil."

He also said he appreciates what the trike does for his health, as well as the money he's saved by not depending on gas. He has needed to fill his car only twice with gas since building the trike.

"I would like to point out that since an average American spends between $150 to $200 on gas every month, my DIY electricity trike has paid for itself already," Wu noted.

Other than the health and cost-saving benefits of the trike, Wu said one of his favorite aspects of riding is the people who stop to ask about it.

"Every time people go by, they say ‘wow,’ and I tell them ‘this is a horse that doesn't need feeding,’ " he said. "They’re so impressed and interested."

Bin Wu sits in his solar-powered trike he made by hand last week on Francis Quadrangle at MU. Wu, an engineering professor at MU, said it took two to three weekends to create the machine. "I take it out on trails when the weather is nice," he said. The tricycle only cost Wu $500 to create.

Since graduating in engineering from Brunel University in London, Wu has become an internationally recognized expert in the design and management of manufacturing and supply systems.

Since moving to Columbia in 2000, he has taught students about engineering in relation to industrial systems design and energy efficiency.

Although his initial goal was to show students how knowledge could be transformed into something real and sustainable, he now wants to spread the word about solar to the rest of the community.

"It's really my wish to let them know what is possible and how wonderful it is," Wu said. "You do not have traffic, your mind is totally free, it's an enjoyment, and you don't have to pay for gas."

Wu also emphasized that the trike is far better for the environment and is a more reasonable replacement for a car than some might think.

A 2021 study by the U.S. Department of Energy discovered that on average, more than 50% of daily trips made by car drivers cover less than 3 miles.

"And a majority of these short trips only involve the driver," Wu said.

Knowing this information and the joy the trike brings him, Wu said he decided to use his car only when necessary.

"My plan is that I am not going to use my car in the future," he said.

Community reporter, spring 2023. Studying journalism with an emphasis in news writing and reporting. Reach me at [email protected], or in the newsroom at 882-5700.

Visual journalism reporter, second-year graduate student studying photojournalism. Reach me at [email protected], or in the newsroom at 882-5700