Treat Yourself to M&M
Shortly after deciding to install a submeter in his New York City building, Mr. Facility Manager discovered a 400-kW spike in his facility's electric profile one day in June. Upon further investigation, he found that his utility operator apparently decided to slack off, leaving the chiller running at full blast all day.
Shortly after deciding to install a submeter in his New York City building, Mr. Facility Manager discovered a 400-kW spike in his facility’s electric profile one day in June. Upon further investigation, he found that his utility operator apparently decided to slack off, leaving the chiller running at full blast all day. The result? The facility’s peak demand was bumped up, resulting in an additional $20,000 tacked on to the electric bill.
While nothing could be done retroactively, the new meter should prevent such an incident from occurring in the future.
In another case where a submeter was installed on a boiler at a testing laboratory, it came out that an energy management system programming mistake was triggering an air damper to open for a few hours in the middle of the night. This error was causing excess air to enter the facility, thereby forcing the boiler to work harder the next morning.
This had been going on for years at a price tag of thousands of dollars, but without a submeter it would have never been discovered.
Running the Numbers
In addition to discovering costly errors, the main benefit of metering and monitoring technology is simply being aware of how much electricity is being consumed and where it’s going.
“You can’t manage what you can’t measure,” says Gilbert Shaw, a market unit manager with Enterprise Energy Management Group, Alameda, Calif.
Armed with such valuable information, facility managers can then load-shift at peak demand times to avoid buying power when it’s most expensive, and make appropriate building system adjustments or changes.
“More and more facility managers are realizing that by employing sophisticated metering and monitoring equipment, they can improve the cost of electricity and improve its quality and reliability,” claims Alan Mayzenberg, P.E., director of electrical engineering for EwingCole, Philadelphia.
But even though the arguments for metering are convincing, submetering technology has only penetrated regions of the country where power is more costly.
“It’s a mature niche, but it’s still a niche,” according to Don Millstein, president, E-Mon, Langhorne, Pa.
“It depends on how energy pricing is affecting the market,” notes Ben Guth, P.E., a project electrical engineer with Power Engineers, Boise, Idaho. “They [end users] either want a whole bunch of metering or none at all.”
Lindsay Audin, president of Energywiz, Croton, N.Y., explains that “energy-intensive facilities have been doing this stuff for years,” especially since electricity can easily account for up to 90% of their monthly expenses.
For example, says Millstein, when he approaches these particular end users, “We go in there and say, ‘Look, you have a million, or even $10 million electric bill every year. Wouldn’t it pay to invest in submetering to see where that energy is going?’ They can see where they’re wasting energy. Change equipment or load shift and it goes right to the bottom line with minimal investment.”
And according to Hugh Lindsay, manager of British Columbia-based Power Measurement’s commercial, government, information, communication and technologies markets, it’s an easy sell, as most industrial facilities “have already bought into the idea that metering and monitoring is a good idea for them.”
But for commercial facilities, where energy falls between 1% and 2% of overhead, the cost of electricity has to be expensive enough—usually around 10 cents per kilowatt hour—to make submetering worthwhile. “When the cost of electricity becomes double digits, submeters seem to spark interest,” says Audin.
Also, if the payback is attractive—less than three years—end users are more likely to consider the investment. “You have to make an economic case to acquaint an end user with the time value of energy,” Audin explains.
For example, for a typical 100,000-sq.-ft. facility, it usually takes no more than a dozen submeters—installed in key places such as the chiller, cooling tower, large air handler, elevators and common area lighting—to realize at least 2% energy savings, he says.
Another incentive is demand response programs, offered by utilities in some areas of the country. Where this is the case, utilities actually pay end users to load shift during peak demand times in order to help protect the integrity and reliability of the grid.
Currently, demand response programs are most common in places where electrical capacity is an issue, such as California, the Chicago area, Minnesota, parts of Iowa, the Northeast and the mid-Atlantic region, including Pennsylvania, Maryland, New York and New Jersey.
“There are a lot of demand response programs and more are coming on,” notes E-Mon’s Millstein.
Some government agencies are even offering rebates for installing metering, such as the New York State Energy Research and Development Authority and the California Energy Commission. And others have packaged metering data as value-added services in the form of end-user usage profiles. According to Millstein, utilities sometimes offer such perks as part of their customer retention program, or they may sell the service to create more revenue.
Case in Point
But regardless of whether demand response programs are offered as an option to end users, the positive experience that many facility managers have had with metering and monitoring equipment serves as convincing testimony.
For instance, a pharmaceutical process plant was considering adding another 2,000-kVa substation to meet its power needs. However, once Mayzenberg assisted them with the installation of submetering, they discovered that a number of existing transformers were only loaded 40%. Consequently, they had much more capacity than they had thought, and essentially saved the millions of dollars it would have cost to building a new substation.
In another case, a New England foundry was under the impression that 60% of its energy use was being consumed by process A, while the remaining 40% went to process B. As a result, the manufacturer was considering relocating part of its operations to a place where power was less expensive. However, “with meters, they found out that the reverse was true,” explains Millstein. “They took that information to management, stayed in New England and saved money.”
Millstein also mentions a situation involving a building owner who was utilizing 10-year-old leases to rent out office space. After installing meters, this landlord discovered that his tenants were using twice as much power as they were a decade ago. With this information, he was then able to make the necessary adjustments in their leases.
Oftentimes, owners will actually realize savings with no further investment than the meters themselves. “A university that we were worked with had a sense of where its energy was going, but no real detail. They used metering information to tweak their building automation system and modify their cooling system. It cost them nothing and they managed to save $40,000 per month, during the summer months,” relates Lindsay.
One situation where energy management software proved invaluable was for a pharmaceutical company during the Northeast blackout last summer. Being that an unplanned loss of power is detrimental for production, facility operators were able to avoid this by using the system to properly shut down the equipment before power was cut off by the utility.
Although there are countless examples of end users cashing in on metering and monitoring, one area where they can easily be overwhelmed is information overload. Basically, a typical interval meter takes a reading every 15 minutes. So, in a 24-hour period, that’s 2,880 data points. And in the old days, meter readings had to be recorded manually, albeit less frequently, which was quite a cumbersome task.
But today, in order to manage reams of data, sophisticated software is employed to “take raw energy data and turn it into actionable information,” says Lindsay. Referred to as a data acquisition system, such software organizes and presents the information in a readable form, in addition to notifying the end user when things are out of the norm.
However, in some cases, this may still not meet an end user’s needs. “The problem is that corporate engineers either don’t have the time or experience to run the software and do the evaluation of the information coming from the meter,” claims Guth. “They have all this great information, but they don’t know how to implement it.”
Fortunately, meter data service providers take it a step further installing meters at no cost to the end user and then charging a monthly fee to manage the data on behalf of the building owner. “Without such a system or service, you’re pretty much up the creek,” claims Audin. “It’s useless to do metering without it.”
Although many software packages offer both basic and advanced functions, it’s been Millstein’s experience that end users prefer to grow with the system, starting out at a more elementary level and then adding functionality as they get comfortable with the system. In a nutshell, Millstein likes to offer a buffet of functionality and services, what he calls a “Chinese menu,” and let end users choose what they want to serve their individual needs.
In general, the way most providers operate is they send a technician out to spend a day with the end user both to install the system and offer training, explains Millstein. For follow-up, operators then have access to a technical support number.
While technical support for metering and monitoring appears to be adequate, says Robert S. Butt, Jr., P.E., project manager with The RMH Group, Lakewood, Colo., end users are still underutilizing the equipment.
“This is primarily due to the complexity of learning additional features beyond the basic desired ones, and then remembering the equipment operating procedures, i.e., menu structures, selection and adjustment, alarm codes, etc.,” claims Butt. “In many cases, facility personnel do not have the time to learn, and relearn, all the details associated with setup, data acquisition and analysis.”
As the technology continues to improve, Audin predicts that things will become more simplified for end users. “We’ll eventually see software that can look at a load profile, figure out what needs to be adjusted and do it automatically,” he says.
Audin adds that as chips become less expensive, this will also affect the affordability of metering and monitoring: “We’re always looking at ways to reduce installation, communication and maintenance costs.”
End users can also anticipate getting more bang for their buck as more functionality is built into the equipment. “Advanced metering on the market is already providing not just kWh and demand, but power quality information as well,” says Millstein.
“Robust meters can look clear to the 63rd harmonic,” concurs Guth.
Another big area where manufacturers are making advancements is in communications. Over the past few years, communications capabilities have evolved from fixed, wireless networks to public networks utilizing telephone lines, and now Ethernet.
“With Ethernet, end users can look at meters in real time, do some alarming and set thresholds,” claims Millstein. “Once you’re on that Ethernet line, you can get that data as often as you want. It’s a cost-effective way for a poor man’s energy system.”
Taking it a step further, the next thing on the way is satellite communication, which would be ideal for remote locations because “running an Ethernet line to places where you don’t need Internet connectivity, like remote sites or substations/towers sitting in the middle of nowhere, may not be cost effective,” according to Millstein.
But whatever the case may be, submetering, and its accompanying management software, has already proven to be a wise investment and is expected to continue doing so.
Submetering systems are commonly used to measure energy consumption, allocate tenant or departmental costs, monitor power quality and reduce peak demand charges. They have also evolved into essential data-gathering tools for predictive equipment maintenance and operational process improvements. In recent years, the demand for a comprehensive summary of energy usage has resulted in submetering software that integrates the entire spectrum of facility resources, including electricity, gas, water and steam. These new energy intelligence systems provide property and facility managers with a total building “snapshot” and help them understand when, where and how energy is being used.
These systems also enhance building automation and industrial process systems by monitoring equipment loads and using this data to optimize control parameters. Historical tracking of electrical demand (kW) and usage (kWh) graphically depicts how energy-intensive equipment, such as HVAC systems, compressors and production lines, contribute to peak demand. This data can then be used to shed or move non-critical loads, diagnose inefficiencies and improve equipment performance. The operator can also evaluate, in real time, whether or not specific peak-shaving activities are delivering the requisite reduction in energy use.
Businesses can also use load profiling for trend analysis and predictive maintenance. Evaluating the performance of pumps, compressors, heaters, chillers, conveyors and other electrical-powered loads requires accurate, real-time status feedback. The graphical summaries provided by new submetering software give facility and plant engineers the information they need to predict service requirements.
For example, the upward trending of the power draw on a generator or compressor could indicate worn bearings and allow the operator to schedule maintenance before an unexpected and costly outage occurs. Or, a ragged demand profile may lead to the discovery of a failing valve or inappropriate gate settings.
In operation, the submetering system accumulates energy consumption data from a variety of sensors, digitizes it and relays it to a host computer via RS485 cable, a modem or other communication devices. This information is date/time stamped and transmitted via data cable, modem or standard RF technology to authorized users. The most recent generation of energy intelligence systems also offers compatibility with popular building energy management and industrial control systems, either through Ethernet/IP addressability or ModBus RTU protocol.
The Internet has become another valuable resource for helping users track and analyze their energy consumption—from a single circuit in one facility to multiple sites around the world. This service tracks usage of electricity, water, natural gas, oil and steam from an Internet browser—in real time. Other popular functions include viewing load profiles and weather data on a weekly, daily, hourly or more frequent basis, as well as setting energy-usage threshold alarms via the browser.
Customizable energy intelligence software permits access to data points from any location and can be interfaced with most existing energy management or BAS. Systems that also accept external inputs from water, gas and other meters provide a comprehensive summary of facility resource consumption. This critical data can be used to reduce costs, improve operational efficiency and provide incentives for energy conservation.
Metering and Monitoring, Southern Style
The Commission of Public Works in McCormick, S.C., located next to the Georgia border, operates a number of infrastructure systems, including a town-owned wastewater treatment facility and a distribution system for electrical energy that it purchases in bulk from South Carolina Electric & Gas (SCE&G).
Recently, the wastewater treatment facility was expanded to handle flow from neighboring developments, as well as its own water supply. Because the facility uses a UV decontamination system, electrical power reliability is critical to the safety of the water supply, because without power, there is no decontamination process. Consequently, state and federal regulations required that the town install a backup generator.
Because it also acts as an electrical power distributor, McCormick had a unique opportunity to manage its wastewater treatment facility and its electrical distribution system symbiotically. By controlling load in the wastewater treatment facility and cogenerating power into the electrical distribution system, the town would be able to reduce its peak demand levels, thereby avoiding high peak demand charges and lowering its overall cost of electricity.
The McCormick Commission of Public Works came up with an innovative solution to maximize its investment in the necessary generation assets for the wastewater treatment facility. Instead of installing a basic generator with simple on/off functionality that would be incompatible with the peak-shaving scheme the commission had in mind, they chose a more sophisticated system that offered a stepped approach to generation. The new 1,000-kW diesel generator offers seven stages of functionality from off at Stage 0 to maximum generation at Stage 6. A 2,500-gal. fuel tank was also installed to provide a substantial reservoir for the generator in case of an emergency power interruption on SCE&G’s end.
To complete the peak-shaving system, an energy-monitoring system was also required. Comprised of two meters and enterprise software, the technology provides the complete data and information-gathering network that is needed to run McCormick’s integrated power and water treatment facilities. It acts as the central nervous system, allowing individual elements to work in conjunction toward the goal of cost-effective and reliable municipal services.
One meter monitors the incoming utility service at the main substation where the utility load for the town is monitored. This meter provides an accurate reading of utility power levels for demand control, as well as providing detailed data that can be used for bill verification to ensure accurate billing on the part of the utility.
The other meter monitors and controls the generator at the treatment plant. A workstation running the software is located at the treatment facility as well. The substation meter is connected to this workstation through a continuous modem link and the generator meter is connected through an RS-485 serial connection.
The generator switches on when the utility reading reaches a set-point value. The generator output makes up the difference between the current load—power consumed—and the defined peak-shaving set point. As demand grows above the set point, the generator is stepped up to increasingly high output levels. When demand levels drop, the generator switches down to lower stages until it switches completely off. The stepped approach allows the generator to tailor its output to best meet the demand, minimizing wasted capacity and less money is squandered on fuel and generator maintenance.
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