HANOVER, N.H. - Dartmouth College is installing a Spinwave Systems mesh network based on Spinwave sensors to monitor and manage its heating, cooling, and electrical systems across the campus, the company has announced. The network encompasses more than 200 pulse counters to transmit data every 15 minutes from meters in 125 college buildings spread out over 250 acres on the Dartmouth campus in Hanover, N.H.

Spinwave, a leading sensor and mesh network company, uses a patent-pending implementation of IEEE 802.15.4, a very low-power-consumption data communication protocol. Spinwave’s version adds a self-adapting frequency agility that shifts the signal from channel to channel within the 2.4 GHz radio band (used by WiFi, many cordless phones, and Bluetooth) to avoid the interference that can occur with other versions, said the company.

The college expects to reduce fuel requirements by 5 to 15 percent a year and it expects to recoup its expenditures on the new system in a year at the 5 percent reduction rate, according to Stephen R. Shadford, Dartmouth’s energy engineer in charge of the project. The college has operated a pilot installation since March 2009; full implementation began in January and it is expected to be completed this summer.

“We’re very pleased that Dartmouth selected Spinwave as its partner in this challenging implementation, and that the college will recoup its investment so quickly through the energy savings,” said Rainer Wischinski, vice president of marketing for Spinwave Systems.

“Now, we can analyze equipment use, factor in weather forecasts, and adjust the system appropriately, while also locating problems like faulty meters and leaking pipes,” Shadford said. “We can fix, optimize, and really use the system.

“Spinwave has the full range of products we need and they are purpose-built for this application. This is a very wide area network,” said Shadford. “It’s not a generic mesh network. It’s elegantly simple to install. You just connect two wires and [the pulse counter] starts sending to the gateway.”

The monitoring system Dartmouth is replacing is a collection of dozens of freestanding, almost entirely un-networked meters located across the campus. The college uses a central steam plant for heating campus buildings and the meters in each building measure the amount of steam that has condensed into water, and electricity consumption. For the most part, the college had four people whose job it was to walk around the campus, recording readings by hand once a month.

Because the data had been collected and entered on a monthly basis, it was impossible for engineers to develop a load profile (a snapshot of current usage) or to adjust the system operation in response to current requirements. For the college it was, Shadford said, “like getting your bill from the fuel company once a month.” In addition, if a meter failed, it might be weeks before the failure was even discovered, losing valuable data in the meantime.

“We’ve gone from one data point a month [per meter] to 3,000 a month,” Shadford said.

For more information, visit www.spinwavesystems.com.

Publication date: 08/09/2010