Small adjustments in energy use add up to big savings when spread among public buildings throughout a county or state; but pinpointing air conditioners that can afford to run one degree warmer or air exchangers that could use a shot of WD-40 in these scattered facilities is a daunting proposition.
With a crippling energy crisis not long behind them, it's no surprise that two government agencies in California have harnessed IT to help cut energy consumption and costs. As part of its Enterprise Energy Information Management System (EEMIS) program, Los Angeles County implemented the EEM Suite from Silicon Energy to help analyze its use of power. And California's Department of General Services (DGS) uses WebGen Systems' Intelligent Use of Energy (IUE) system to monitor consumption in more than 60 state buildings and automatically control its use of power in about 45.
In Los Angeles County, the EEMIS program's goal is to collect data on energy consumption in the county's largest buildings and use that information to cut energy use, said Howard Choy, energy division manager with Los Angeles County's Internal Services Department. Some savings will come from strategies that allow existing equipment to operate more efficiently; other improvements will come from replacing climate control, lighting and other systems using older technology.
Los Angeles County spent a year exploring energy management systems before it began implementing the EEM Suite in June 2001, Choy said. The county now has about 80 buildings connected to the system and hopes to expand that to 150. Los Angeles County uses more than 60 million square feet in more than 2,500 buildings, but these target facilities account for about two-thirds of its energy use, he said.
The EEM Suite employs data collected in near real time from meters and electrical devices to produce a variety of energy consumption and cost reports. Silicon Energy's customers run the software on servers in their own facilities; users access it through a Web browser. Los Angeles County paid $1 million for the software and its implementation. In each building, the county installed hardware to collect data and transmit it to the central server. Equipping a typical building to collect only utility meter data costs as little as $2,000. Buildings can also be equipped to gather as much information as desired from additional devices, Choy said.
Spot the Spike
Viewing the software-generated reports, it's easy to locate consumption spikes and problems, Choy said. "Every time we look at an operating profile of a building, there's typically something to see that raises a question," he said. "Why is this spike here, or why did this equipment come on at two or three in the morning?" Unfortunately, the reports present more data than anyone can absorb.
In the next phase of EEMIS, the county will manage by exception. When operations in a building fall outside established parameters, Silicon Energy's software will send an alert.
For example, the county can define the highest consumption level a building should reach. That number is important, Choy explained, because for nonresidential customers, utility companies base half the monthly bill on the "demand charge" -- a charge defined by the peak consumption level for the month.
"We can look at what that high point has been historically, and we can establish an alarm when we get to 75 or 80 percent of that level," Choy said. "When we get the alarm, we can investigate circumstances and implement procedures in the building -- for example, ramp back on certain pieces of equipment -- so we don't exceed the next level and get hit with higher charges."
The county has not used EEM Suite long enough to quantify its benefits, but the potential for improvement is clear, Choy said.
Other public-sector customers using Silicon Energy's software include Sacramento County, Calif., and California State University at Long Beach.