University cuts annual water costs by $70,000 with data loggers
Above: With more than 27,000 students, Plymouth University in England sought efficiencies for its water use.
Plymouth University is the largest university in southwest England. The 1.6 million-sq-ft campus has approximately 50 buildings to house its more than 27,000 students. With such a large community, it is no small task keeping up with the high demand for water resources. Seeing to that demand is Paul Lumley, Plymouth University’s energy and environmental manager. Lumley’s responsibilities include meeting the university’s water needs while also identifying and reducing waste in the infrastructure.
Gathering Water Data
When Lumley assumed his responsibilities several years ago, the campus had room for improvement. Annual water usage was about 11 cu meters per student, and there was no comprehensive system in place to keep track of how the water was being used. Although some buildings were individually metered, many of the smaller buildings shared meters. Lumley had some initial success in lowering water usage by installing flow restrictors and pressure-reducing valves, but he wanted to take it a step further.
“You can’t effectively manage a resource when you can’t track the quantity that you’re currently using,” Lumley said.
In 2011, Lumley made the decision to deploy data loggers at 21 sites around the campus to give him a better idea of where the water was going. The devices, COMLog data loggers from HWM (known as Fluid Conservation Systems in the U.S.), measured water usage every half hour and wirelessly transmitted data twice daily to a web-hosted server, Datagate. The server then distributed the data to the local water utility company as part of the university’s resource management strategy.
The data loggers use accumulative pulse counting technology to calculate index readings against a known volume. They are compatible with any meter that has a volt-free, pulsed output. The loggers use internal general packet radio service technology for rapid data transmission at a low cost. Even with increased transmission rates, the low-power electronics enable a battery life of five years. The units also are available with external battery packs to maintain the five-year life span should the user choose to transmit data at an increased rate.
Data loggers transmit water usage twice each hour to a web-hosted server. The information was used to develop a resource management strategy.
Analysis & Savings
The data loggers let Lumley see water usage information for each area monitored, and how usage fluctuated based on the time of day. In addition to identifying potential leaks quickly, Lumley could monitor trends in specific buildings and alert staff of any wasteful or unintended use.
“The information is paramount to affect behavioral change,” Lumley said. “I can think of two instances where I’ve relayed information to building users regarding large consumptions caused by equipment. Staff have responded really positively once they see and understand the need to improve control, and the related cost savings.”
Lumley’s conservation attempts were a success. Plymouth University’s water usage rate dropped from 11 to 3 cu meters per student—a reduction of more than 2,100 gal per student per year, saving the university more than $70,000 in water consumption costs.
Paul Lumley, Plymouth University’s energy and environmental manager, installed data loggers at 21 sites to track water usage throughout campus. The information was shared with the local water company to help manage water resources.