THE ENERGY YOU USE MAY BE YOUR OWN

Whether or not oil supplies are peaking may be a matter of controversy but it is abundantly clear that cheap energy is nothing but a memory. Efficiency is a necessity. Beyond energy efficiency is energy scavenging. Max Poulshock, president, Thermo Life: "Energy-scavenging has been around for years, but because of the fuel crisis, everyone from big companies to small ones is looking to utilize it…It's a very hot topic."

The idea is that any movement creates some kind of vibration or recoil from which watts or microwatts could be harvested and used for small tasks like charging a cell phone or driving a pacemaker. Even an existing temperature differential creates energy that can be harvested.

Max Donelan, kinesiologist, Simon Fraser University: "People like the idea of generating their own power…If you do things in a clever way, you can get energy cheaply."

As the article reveals, there is no end to the power of human creativity to find useful energy. That is fortunate because U.S. political leadership is lagging behind in the building of a 21st century energy infrastructure. As the author of the article says, “there’s not a watt to waste.”

In the same way a hybrid car captures braking energy and turns it into battery-charging power, this brace captures leg-stopping energy and stores it. (photo by Greg Ehlers - click to enlarge)

Finding Energy All Around Us
Bryan Walsh (w/ Laura Blue and Bruce Crumley), March 6, 2008 (Time Magazine)

WHO
Max Donelan, kinesiologist, Simon Fraser University; Arthur Kuo, biomedical engineer, University of Michigan; Max Poulshock, president, Thermo Life; Steve Beeby, engineer, University of Southhampton/director, EU Vibration Energy Scavenging Project; Roy Freeland, CEO, Perpetuum; Jean-Jacques Chaillout, French Atomic Energy Commission; Rama Venkatasubramanian, thermoelectric expert, RTI International

Vibration energy can be captured and stored as electricity. (click to enlarge)

WHAT
Energy scavenging: harvesting small and otherwise wasted watts and microwatts.

WHEN
The era of cheap energy is gone. Time to get energy anywhere it is.

Via the thermoelectric effect, a temperature difference can drive electrons, generating an electrical current. (click to enlarge)

WHERE
- Beeby’s vibration harvester can collect a bridge’s vibrations to drive its illumination or power sensors that monitor its structural integrity. Or it could collect a heart’s vibrations to drive its pacemaker.
- Chaillout thinks his piezoelectric device can be used inside nuclear reactor towers where there is a constant drip of condensing water after the reactor has boiled water into steam to drive the plant’s turbine.
- Poulshock’s Thermo Life has a system to generate energy from temperature differentials.

WHY
- Donelan’s knee braces collect 5 watts (enough to charge 10 cell phones) of energy from gait applying the principles of regenerative braking used in gas-electric hybrid vehicles.
- Beeby created a vibration harvester: Anything that vibrates moves a magnet inside a copper coil, generating an electrical current. Bridges vibrate. The human heart vibrates.
- Chaillout has devised a way to collect a microwatt from each falling raindrop using a 25-micrometer-thick (a thin human hair) strip of piezoelectric (electricity-sensitive) material.

Thermo Life wants to use the thermoelectric effect or another form of energy scavenging to drive medical devices. (click to enlarge)

QUOTES
- Steve Beeby, engineer, University of Southhampton/director, EU Vibration Energy Scavenging Project: "It's very unlikely on a big scale…It will never compete with wind power or anything like that."
- Roy Freeland, CEO, Perpetuum: "[In the human heart] there's no source of power but plenty of vibrations…You can just fit [a pacemaker] and forget."
- Jean-Jacques Chaillout, French Atomic Energy Commission: "When you add up all the materials and costs in powering, battery production and charging you save with [piezoelectric strips], it really adds up…"
- Rama Venkatasubramanian, thermoelectric expert, RTI International: "Sixty percent of the world's energy is wasted as heat…If we could tap into just 10% of that, it would be a big thing for energy efficiency."