Self-Powering, Wireless Energy Sensors Join the Internet

EnOcean's self-powering sensors -- found inside these switches -- can now communicate via TCP/IP, eliminating the need for pesky wires. Photo courtesy of EnOcean

Humans are inherently inefficient creatures. We leave lights on needlessly, keep the home thermostat cranked up with the windows open, forget to turn off our televisions when we leave the house.

And despite the advances in computing power over the past few decades, our buildings aren’t doing anything to make up for our inefficiencies.

“Most buildings today are dumb,” says EnOcean Chairman Graham Martin, “meaning they completely lack automation systems to manage energy use.”

EnOcean wants to change that. The company created a self-powered, energy-harvesting sensor, which which can be found inside of the inexpensive, easy-to-install light switches and thermostats EnOcean manufactures.

Now those sensors are able to communicate via TCP/IP networks, which means that when installed, the energy use of any web-connected building can be managed from another web-connected device.

EnOcean’s sensors are the latest in a wave of increasingly connected and intelligent objects that some people have termed “the internet of things.” British microprocessor giant Arm Holdings, for example, has bolstered this development with its mbed project, which gives engineers a cheap toolkit to work on a microcontroller, and the encouragement to come up with novel ways to connect them to other (often unconventional) objects. Other companies, like EnOcean and semiconductor maker Atheros, are focused on developing low-cost, low-consumption devices that can operate on wireless networks.

Pressing an EnOcean switch to turn a light on generates enough energy to send out a wireless signal, which enables communication between the switch and a wireless receiver up to nearly 100 feet away. Until recently, EnOcean sensors were only communicating amongst themselves and a specific wireless receiver within range. Now, with TCP/IP enabled communication, any computer hooked up to the internet can communicate with the sensors.

These sensors are cheap and easy enough to install that EnOcean foresees a wide market for them. Current industrial automation systems can cost hundreds of thousands of dollars to install, not to mention the need to rip open walls for installing hardwired energy management sensors.

EnOcean’s sensors eliminate those costs. At approximately $50 to $100 a pop (depending on the type of measurement needed), EnOcean’s switches are peel-and-stick; there’s no need for messy construction crews to tear down your drywall. Instead of batteries, the sensors capture energy from their surroundings using a combination of solar cells, thermal and linear motion converters. That means they’re completely self-powering.

With the flick of a switch, for instance, the Eco 100 linear motion harvester converts the movement of an internal spring into a small amount of usable energy (around five volts). This is enough to transmit the wireless signal without the need for a separate battery to power the operation. No muss, no fuss.

The sensors have already been installed in over 100,000 buildings already, consisting mostly of retail establishments and commercial buildings. But EnOcean has its sights set on wider, more mainstream applications, such as college dorms, hospitals or your house.

Can2Go's Android app lets you control your thermostat from the comfort of your smartphone. Photo courtesy of Can2Go

Installing them is easier than you may think. After hooking up a gateway device — which looks and works much like your everyday router — EnOcean sensors use internet protocol-based communication to relay temperature settings and energy use to the server. You can access that info via a widget from any internet-connected desktop or laptop, whether you’re at home or not.

And yes, there’s an app for that. Android, iPhone and BlackBerry users can install remote access apps like VenergyUI or Can2Go, which let you monitor and control your home energy usage from your smartphone.

Of course, it’s a cost-efficiency thing for larger enterprises. “Where we?re seeing the most savings are the buildings where people don?t pay for the energy themselves,” Martin said. “Hospitals, hotel rooms — there’s no incentive to turn off the heater when you aren’t paying for it in your bill.”

Realistically, you probably won’t be saving wads of cash by installing one in your own home. It’s an idea that appeals to scalable business models and larger operations.

Still, any idea that lets you crank up the heat in your place before you get home at night, all through the use of your smartphone, is okay in our book.