When Jason Vogelbaugh, director of Energy Solutions at Alpha Controls & Services, (Schneider Electric’s Rockford, IL, partner) visited Busey Bank’s 100 year-old Executive Center building in Champaign, IL, he saw problems - and enormous potential. “It was ‘the poster child’ for buildings of this vintage,” recalls Vogelbaugh. “The entire building was one zone, running either at full heating off an ‘antique’ boiler system and 2-in. perimeter steam heat, or full cooling, from three circa 1970’s rooftop units (RTUs). Ostensibly, we were there to quote new controls on one of the RTUs, but I found an extremely receptive audience at Busey Bank for making the significant across-the-board improvements in energy efficiency that are almost always possible in an older building.”
Busey Bank promises its shareholders “Balance Sheet Strength, Profitability and Growth,” and they deliver. The U.S. Department of Agriculture Rural Development in Illinois selected Busey as its 2010 Top Lender, and it boasts an impressive balance sheet of $3.6 billion in total assets, 30 full-service, and four teller-service branches serving downstate Illinois, and other branches in Indianapolis and southwest Florida. The thought that the bank could actually be ‘bleeding’ precious energy, and dollars, at its Champaign office building (part of its headquarters campus) was particularly troubling to Donald J. Schlorff, Busey Bank executive vice president.
“To say that Busey runs a ‘tight ship’ where costs are concerned would be a bit of an understatement,” says Schlorff. “In this challenging environment for banks and businesses alike, we’re keenly aware of operational cost - and at the same time the need for green, sustainable practices. What Jason was able to tell us about the building was a real eye-opener.”
ANALYZING ENERGY USE FOR SAVINGS
Armed with Busey Bank’s utility bills, Vogelbaugh put Schneider Electric’s EnergyEdge to work, a proactive process used to assess and analyze a facility’s energy usage and costs, and then create and implement a program that results in sustained energy efficiency and what are generally substantial savings.“Typically, facilities are managed reactively, meaning obvious problems are fixed as they arise, but little is done proactively to counter ever-rising energy costs,” says Vogelbaugh. “But EnergyEdge makes it easy, and in the case of Busey Bank it quickly confirmed what we suspected. For example, we determined that the building’s annual electricity usage was about 1.8 kWh - or 2-1/4 times greater than the typical building of this size and type. We also could see that the 3-million-Btuh boiler system was running at about only 60% of its nameplate rating, meaning there was an enormous potential for saving ‘therms.’ Where the average energy savings determined by using EnergyEdge is generally around 20%, Busey Bank was clearly going to be significantly greater.”
Making the project even more attractive to Busey was the exceptionally short ROI period, adds. Schlorff. “Clearly, the energy savings would be significant, but there was also a powerful additional incentive through our electric utility provider Ameren Illinois and its Act On Energy® program,” he says. “Ameren’s program provides businesses with financial incentives for upgrades of older HVAC systems. Ultimately, we qualified for a 20% rebate (or $18,178) on the total project cost, which essentially gave us a new Schneider Electric control system practically free.”
Vogelbaugh also predicted that electricity savings would put Busey Bank on a new rate schedule with its utility, ultimately reducing electric rates from a current 9 cents per kWh to perhaps as low as just 6 cents/kWh, providing yet another powerful incentive.
RECOMMISSIONING: COMBINING HVAC BRAINS AND BRAWN
With the green light from Busey Bank and Vogelbaugh, Alpha Controls and Schneider Electric proceeded full steam ahead with a recommissioning project fairly typical of a building of this size and type.“We install building automation system ‘brains’ so that the building can detect, and react swiftly to, even the most subtle building load changes caused by solar load, outdoor air temperature, humidity, and even occupancy,” says Vogelbaugh. “We design and install a system of rugged field devices to provide the ‘muscle’ to work dependably around the clock. Schneider Electric gives us the complete range of solutions so the process of installation and integration is that much easier.”
A good example is the work done by Alpha Controls on the rooftop air conditioning units, starting with RTU #1. This vintage ‘70s rooftop unit was originally designed to run at constant volume, so the fan always operated at full speed regardless of outdoor air temperatures or internal load conditions, accounting for considerable energy waste. But by installing a Schneider Electric Altivar VFD, it now became possible for fan motor speed to be matched exactly to changing load requirements within the building, and either increase or reduce fan speed and corresponding outside air volume accordingly.
Installation of Schneider Electric S-Link temperature sensors and thermostats provide building heat load control. When, for example, a thermostat calls for cooling, a Schneider Electric I/A Series MNB-1000 Plant Controller activate one of four cooling stages and instructs the VFD to increase fan motor speed accordingly - and to reduce speed just as quickly and efficiently as soon as the desired temperature is detected. Similar controls were then installed on RTU’s #1 and #2 so that the entire A/C system now operates with vastly improved energy efficiency.
In fact, Vogelbaugh has documented that Busey Bank reduced its kwh usage over the course of 12 months from 1.8 million kWh to just 1.2 million kWh, or a 30% savings. And in addition to the savings in electrical energy, substantial natural gas savings in winter would be realized as well, since far less cold outdoor air would be brought inadvertently into the building.
But perhaps the ‘800-lb HVAC gorilla’ in the building was the steam heating system. EnergyEdge had shown that the two 2,500-gal, 3-million-Btuh antique condensing boiler systems were running at just 60% of nameplate efficiency, consuming and unecessarily wasting thousands of natural gas ‘therms’ a year. While there was nothing inherently wrong with the boilers themselves, the complete lack of separate space temperature zones, or any way to quickly and efficiently adjust for fast changing building load changes anywhere in the building, had created an incredibly inefficient and uncomfortable, environment.
Alpha Controls instead created 16 separate heating zones, and a network of Schneider Electric DuraDrive zone valves and valve actuators worked to precisely regulate steam flowing through the 2-in. steam distribution piping running to each zone. Schneider Electric Altivar 21 VFDs were installed on the hot water pumps to provide more precise control, along the lines of the RTU fan motors. And Schneider Electric temperature sensors, thermostats, and MNB-1000 controllers were again used throughout the system to provide exceptionally accurate and responsive, heating control in each separate zone based on changes in load, time of day, and the demands of the occupants. Just 12 months after installation, these measures would be shown by Vogelbaugh to have cut annual Btuh consumption in the Busey Bank Executive Center by more than half.
Finally, Busey Bank facilities managers and HVAC maintenance personnel now have access to information and system control capabilities that never existed before, thanks to the use of Schneider Electric’s I/A Series® Controllers. In addition to managing the system, they also provide Busey with a remarkable level of information through an enterprise server that can be used to reduce energy consumption, troubleshoot problems, and perform dozens of other tasks that make life a lot easier - and the building greener and more energy efficient. Now, over the internet or WAN (Wide Area Network), the I/A Series®, powered by the Niagara Framework®, puts powerful information at their fingertips that they never had before - everything from an energy usage trend for the entire building right down to what a thermostat is set at in a particular zone.ES