By James Laughlin, WaterWorld Editor
While many cities across the United States are still reading their meters manually, the trend for the past decade has been to automate that process. Today, however, the latest automated metering infrastructure has evolved to offer much more than simple meter reading. In many cases, fixed-network AMI systems rely on a communication network that reaches to every corner of the host municipality, and opens the door to a range of new functionalities – both existing and yet to be imagined.
"We've probably figured out about 20 percent of what we will eventually be able to do with AMI," said Doug Houseman, Vice President of Technology and Innovations at EnerNex, who specializes in the development of automated metering infrastructure for both electric and water networks.
|Water tanks and towers often serve as mounting points for AMI collector systems. Photo courtesy Badger Meter.|
"I think there will be a lot of smart young kids who come along in the next decade that grew up in an app and computer culture. They are going to look at what we're doing today and say, 'here's three other things that you can do, it's real easy, and I'm doing it on my smart phone'."
Along with improved customer service offered by the wealth of information available from near real-time meter reading, utilities across the country are turning to AMI and its communication backbone to track leaks, manage meter shutoffs, and monitor water quality sensors, pump controls and myriad other functions.
The City of Enid, OK, installed a Wi-Fi system as a backup to its AMI backhaul system. The system allows the city to offer free public access to Wi-Fi in the downtown area, said Scott Morris, Utility Services Manager for the City of Enid, OK. While the Wi-Fi units are installed across the city, most are currently not set for public access. Instead, the system is used by city staff and emergency workers to access city records, maps, and other data.
Morris said one advantage of Enid's AMI system is the staff's ability to recognize particular leak types by the patterns in water flow. He said it took only a few weeks for his staff to recognize the patterns.
"As an example, if you see a leak every other day from 2-4 a.m., that might suggest that there is a water softener that is using too much water," Morris said. "We never tell customers definitively what kind of leak they have, but it gives us a little more ammunition so we can help them figure out their problem."
Enid is testing a system that will allow customers to log into a portal and view their water usage information. Users also will be able to enter their email address to be notified when a leak is detected on their account.
"We actually have so many leaks in the city right now that it's not a viable solution to pick up the phone and try to call every customer," Morris said. "This new system will be an advanced warning system for customers when they have a leak. And that will take the pressure off of us."
Water loss control through the use of district-based metering has been a focus area for Veolia North America, which provides contract operations to cities across the country.
|An AMI transmitter is ready for installation. Photo courtesy of Sensus.|
"We're getting a big bang out of district metering, where we take the distribution network and break it into smaller pieces and meter those pieces to see how water is flowing in and out of the particular networks," said Kenneth Molli, Director of Metering Initiatives for Veolia NA. "That helps us prioritize where we need to spend our money for replacing services."
Veolia is also using its AMI communication network to help prevent overflows in the wastewater collection systems. Sensors mounted in strategic locations monitor the flow of wastewater and transmit information via the AMI system.
In another example of alternative uses for AMI, the company has developed a system for monitoring local area recycling bins that transmits bin status via the AMI network. That allows the company to roll trucks when the bins are full "as opposed to wasting truck runs when the recycle bins are half empty," Molli said. "That's been a recent eye-opening experience."
"The urban environment is pretty complex, and the strategy of Veolia is to harness the power of this communication network and make it do more," he said. Having one network perform a variety of services can help cities "develop economies of scale and do things that really help manage the urban environment."
One key goal of any utility is energy management, and AMI systems can help with that, Houseman said.
AMI systems can convey information from system pressure transducers showing pressure levels across the distribution system, monitor water usage by zone in real time, track storage tank levels and control pumping systems.
"If I can monitor and manage in real time my booster pumps and storage and can get the electric utility to give me an off-peak rate, I can top everything off in the middle of the night – and hold the water towers full well into the morning before I actually release them when the electric price starts to go up," Houseman said.
"If it's all tied together, an AMI system can help you do that, especially if you have pressure transducers in the right places," he said. "You can decide you don't need to open the valves on your water towers, if they are set up that way, and you can reserve that pressure and volume until later in the day."
The AMI system has helped Enid save on energy by limiting truck rolls, Morris said.
"When we shut people off for non-pay, we used to have to send a truck out to keep checking to make sure they didn't turn the water back on. Now we can do those checks from our desk and only roll trucks on ones that have turned the service back on," he said.
"Another pleasant surprise is when someone moves out of a house and someone else is also moving in, we don't have to roll a truck. We can just look in the system, see what the meter read is and bill the customer up to that point, and then start the new customer."
Houseman said some of the utilities he has worked with are looking at automated shutoff systems that would also limit the need for truck rolls, especially in emergency situations.
"Among other benefits, the meter can be shut off within minutes if a homeowner calls in a major leak," he said. "With such a system in place, it typically takes less than two minutes from the time the call comes in to shutoff."
While automated metering infrastructure was initially designed to streamline meter reading, it offers a host of other potential uses.
"I don't honestly know where we can go with AMI in the future," Houseman said. "Since we have the network and we are beginning to have the data, people will start figuring out things we can do with it from a water standpoint, and obviously beyond just water. Cities will look at using AMI to manage all sort of things as we move forward."
Still, accurately metering water and monitoring usage serve as the key drivers for AMI installations. Morris is a big fan of his new AMI system at Enid. He said the system upgrade helped improve customer satisfaction and significantly increased revenue for the utility.
"Just speaking in terms of water loss, before the AMI system, we had a water loss rate of 34 percent. After the system, our water loss rate is 14 percent and we've increased our revenue by 18 percent," Morris said. "Those numbers are hard to argue with.