As part of a senior project supervised by electrical engineering professor Hür Köser, electrical engineering major Henrique Rocha ’09 has devised a mechanism that harnesses the energy generated by a stationary exercise bike at Payne Whitney to charge small electronic devices like iPods and cell phones.
The green workout PRECOR bike, which was retrofitted with the new technology last month, is just a prototype for a larger-scale project the team is planning — a project to harvest the energy generated by gym goers in order to power parts of the gym itself.
“The general idea is that normally all the power generated is dumped in a load,” Rocha said. “Our approach is to extract the energy before it is dumped so that we can do something useful with it.”
Köser explained that most stationary exercise equipment already has a small alternator fitted to it that generates electricity from the user’s motion to power the control panel. But this process is inefficient, since only about 1/10 of the generated electricity is used, while the rest is dissipated as heat. According to Rocha’s calculations, a regular exercise bike could produce 200 to 250 Watts of power — more than enough to power a multitude of small electronic devices.
In fact, if expanded to the remaining 60 machines in the gym, enough energy would be harnessed to power gym light fixtures, televisions and other utility devices — an eventual goal of the project, Köser said. (Specifically, the combined electrical generating capacity would be around 10 kW — enough to power several average-sized households.)
The technology could save a significant amount of energy that normally goes to waste, Köser said, considering that many people charge their personal electronic devices overnight — but charger adapters continue to dissipate energy even after they have fully charged the device.
“If people were to unplug their power adapters as soon as their mobile electronic batteries were charged,” he said, “the savings in electricity and emissions across the country would be substantial.”
As fossil fuel reserves continue to be depleted at an alarming rate, Köser said the project aims to spread awareness about the importance of developing alternative ways of harnessing energy — and inspiring others to think out of the box.
“Our main goal is to raise energy awareness and to show that, little by little, things add up,” he said.
The team, which also includes Bozidar Marinkovic GRD ’11, also has plans to work with the Yale Athletics Department, the Office of Sustainability and Information Technology Services to outfit the entire gym with a wireless sensor network and multimedia information board that will inform users how much energy they are saving, Köser said.
But Bob Ferretti, the education & outreach manager at the Office of Sustainability said the recent budget cuts have stalled the project for the time being.
“Everyone is very excited about the possibility of moving forward with this project,” he said. “[But] given the budget issues the university is facing, we are having difficulty locating the necessary funds.”
At this stage, Köser said, the team is working on gathering feedback from those who have used the bike — specifically, on how long they can go without plugging in their electronic devices.
Of the eight people interviewed at the Israel Fitness Center at Payne Whitney on Saturday afternoon, none had heard about the “green workout” bike, nor tried the technology for themselves.
Still, when told about the idea, all eight responded enthusiastically, adding that they would be interested in using the technology in the future.
“It’s a really good idea — especially if it can be implemented on a large scale,” said Emmanuelle Salgues GRD ’09, who was on a stationary exercise bike similar to the green workout bike.
Brian Young ‘10, who was lifting weights, was also positive about the idea. He said his iPod and cell phone often run out of battery while he is exercising.
“It’d be a great help,” he said.
The Office of Sustainability will administer a survey to obtain feedback about how gym goers may interact with the ‘green’ improvements planned for the gym in the coming weeks, Rocha said.