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1. Limiting the amount of Electricity being used in a 15 minute Electrical Demand Window: The Danfoss system monitors the electrical demand through the primary utility service meter, located at the service entrance to the building. The Danfoss system instantaneously measures the incoming electrical demand and predicts the electrical demand for the sliding 15 minutes period to facilitate a pro-active response to rising electrical demand. This allows the controller to maximize electrical demand savings in real time.
2. More Accurate Refrigerated Space Temperature Control: The Danfoss electronic space temperature sensors are highly accurate and self-calibrating. The Danfoss electronic temperature control provides a 2-degree, ‘start & stop’ temperature range for refrigeration systems. This eliminates over cooling of the space and increases the refrigeration system efficiency. The existing mechanical refrigeration thermostats typically have a ‘turn on/turn off’ range of up to six degrees Fahrenheit. This wide spread in temperature causes the existing mechanical space thermostats to be set lower than the Danfoss electronic space temperature controller must be set at. This means that more energy is required to maintain the same temperature. This is due to the fact that that the refrigeration system must operate longer than it needs to as compared to the more precise means of establishing and regulating the required temperature that is provided by the Danfoss system. Furthermore, when the refrigeration system over cools a space, it accelerates the transfer of cool air to the outside spaces through the walls and ceiling. Finally, as the refrigerated space temperature decreases, so does the efficiency of the compressor(s), which causes even greater, wasteful energy usage.
3. Limiting the Evaporator Fan Motor Run Time: The evaporator fan motors consume large amounts of electricity in two ways. When the fans are operating, the motors use electricity to run. They also produce heat that the refrigeration system must ultimately remove. The Danfoss controller program turns the evaporator fans ‘on and off’ with the refrigeration system. A smart electronic ‘off delay’ allows the Danfoss controller to take advantage of all of the refrigerated air within the evaporator before turning off the evaporator. Another smart Danfoss control program prevents stratification of the refrigerated box’s temperature by monitoring the run time of the evaporators and turning on the fan motors to mix the box air every 30 minutes. This happens if the fans did not run in the previous 30 minutes time period.
4. Monitoring Compressor Status: This allows for the user to see the on/off status of the compressor, compressor short cycle monitoring, compressor off and on cycle timers, compressor total run time and number of current daily run cycles at a central location.
5. Monitoring Refrigeration Compressor Head Pressure: Higher than normal refrigeration compressor head pressure makes the compressor work harder, causing increased wear and electric energy consumption. The electronic head pressure transducers constantly monitor the refrigeration system head pressure and send an alarm signal when the pressures go out of the normal operating range. This informs the EMS service provider and/or the facility’s management, of a minor refrigeration problem (e.g., condenser fan motor failure, dirty condenser coil) before it causes excessive compressor wear, increased electrical consumption, possible safety limit trips, and/or compressor failure. Any of these events could result in product loss. This would be a major liability for this and most customers and has served as yet another motivating factor for the installation of this system by Dairyland.
6. HVAC Demand Load Control and Time of Day Savings: The HVAC controls were upgraded to time of day temperature control with demand load control. This reduced energy usage when the offices are not being used and when peak electrical usage periods are detected by the Danfoss system.
7. Battery Charger Demand and Time of Day Control: This allows the forklift battery chargers to be automatically turned off when peak electrical usage periods are detected by the Danfoss system.

Queens, N.Y. – By moving part of its food production Hebrew National Kosher Foods Inc. received a 60 percent discount on its electric demand rate, but left its energy management system behind. The food company then asked the design and install engineering firm that had installed the system – Energy Consulting Services (ECS) Inc. New York City – to duplicate the EMS at the new location and to improve upon it.

The improvement was the addition of an extensive alarm capability that is preventing costly losses in food spoilage at the new production and cold storage facility according to ECS president Jack Davidoff. By hardwiring 16 analog input points to the system, the plant’s freezer and cooler temperatures can be monitored continuously. When the temperature drifts above setpoint limits, the EMS generates an alarm signal and calls assigned phone numbers, Davidoff said.

This has worked so well in the new system that the older system has been upgraded with the alarm function also, noted Hebrew National’s vice president of engineering, James De Prima. The original 54-point system had no alarm capability whatsoever, and the user did not know when cooler or freezer setpoints were exceeded, Davidoff said. When this happened, though, a mechanical override would bypass the EMS, and equipment would run until someone noticed and reactivated the control system, he explained.

Both the original 54-point system and the new 20-point were designed and installed by Energy Consulting Services, its president Mr. Davidoff said.

The older system at the Queens plant used powerline carrier equipment when it was installed, Davidoff said. “The first job we did for Hebrew National, the user wanted us to do inexpensively,” Davidoff explained. He said the size of the facility in Queens – 100,000 square feet – made it much more economical to use PLC than to hardwire the system.

The system was upgraded with an alarm capability, he added. The new 20-point system was hardwired, Davidoff said. It was less expensive to hardwire this system than to use PLC because the building's electrical service is rated at 480 volts, and this would have required coupling the PLC signals around dozens of transformers, he added.

"The second time around, the user trusted us to do the job properly and show him what it could do," he said. Hebrew National's incentive to split its operation and move some of the food production was largely due to a special "area development" electric rate from its utility company, De Prima said.

A utility spokesman said this rate is available to commercial and industrial users who are willing to move into specified depressed areas. For Hebrew National, this meant a 60 percent discount on its electric demand rates for the next five years, after which the rate will be prorated back up to a non-discounted charge, the spokesman said. De Prima estimates monthly fuel and electric bills at the new location will reach $30,000 when the refrigeration systems begin working at full capacity. He said the demand discount will trim about $3,300 from this bill. The EMS control strategies, which schedule about 20 points of coolers, freezers, air conditioners, and pasteurizes used to sterilize kosher pickles, will save an additional $20,000 per year, he added.

Kearny, N.J. - Goody Products, in seeking an energy management system, bypassed the branch offices of major equipment manufacturers and made its decision based on its regard for the efforts of a local contractor. Energy Consulting Services (ECS), New York, offered the lowest bid, but the user said that his decision was influenced even more by the contractor's thoroughness in his assessment of the Goody facility.

According to John Snyder, director of office services for Goody, "Other vendors simply did a walk-through and based their bids on that. Jack Davidoff - the president of ECS - went up to ceiling, crawled around in back, made measurements, and came in at night to see what was happening, and their estimates were based on 'experience' not data.

Goody also based its decision on recommendations from other ECS customers and visits to previous ECS installations to verify energy savings, Snyder said. ECS's system uses a power-line carrier transmitter to control 42 points, he added.

The installation, completed in January, paid for itself in avoided gas and electricity costs in seven months, Snyder said. Honeywell Inc.'s West-field, N.J., office bid a 23 control point system, according to Snyder. New Jersey Bell Co., now AT&T Information Systems Inc., Morristown, N.J., offered to lease Goody an AT&T system to control 32 points. Timothy McCabe, technical consultant at AT&T Information Systems in Wood-bridge, N.J., said that at the time the bid was submitted, AT&T was only offering larger systems on a leased basis, but the company now has smaller systems that would have been more appropriate for the Goody installation. IBM did not submit a formal bid, but proposed a system that could interface with Goody's existing mainframe IBM computer, at an estimated cost of $100,000, Snyder said. "They wanted to give us more or would ever use," he said.

The ECS bid was selected because it was 10 percent less expensive than Honeywell's offering, but had additional features such as more control points, and because ECS submitted a more in-depth proposal for work to be done, Snyder said. "I could offer a better price because I spent more time preparing my bid than they did," explained Davidoff. "I spent enough time to figure out exactly what needed to be done, so I didn't have to include extras in the bid to cover unforeseen circumstances."

Snyder says Goody is "very pleased" with the services provided. "When the system went in, lots of fine-tuning was required. We were never charged extra for all the tinkering that inevitably had to be done," Snyder noted. The EMS is being monitored and fine-tuned remotely via telephone from the ECS offices, he added. After being hired to install the electronic energy management and control system, ECS proposed and installed a flue gas heat exchanger. Although initial estimates indicated a payback in about two years, the system has saved over $36,000 in the first eight months, and is expected to save $60,000 annually, Davidoff noted. The Goody facility consists of 93,000 square feet of warehouse and factory space, and 8,000 square feet of office space. The system controls the facility's HVAC equipment, including fans, heaters, air conditioners and a hydroponic loop for space heating, Davidoff said. The system performs duty cycling based on temperature set points, enthalpy control, start/stop optimization based on outside temperature, and demand limiting.