You can’t calculate ROI of a metering system any more precisely than you can for a financial accounting system, but experience shows energy monitoring always leads to reducing consumption by 10 to 20 percent or more.
"…. In several of our projects, energy costs for the total facility were reduced 40% or more with no capital improvements required; the savings resulted entirely from changes in accountability, responsibility, operation, maintenance and control that were only possible because of the data from the monitoring system. …."
"There are no magic bullets, no simple solutions for complex problems as so many would like to believe. Energy use in large buildings and systems is very complex. My advice is to return to the fundamentals of good engineering problem-solving and financial management: start by installing instrumentation, gather the actual information, the facts, then view energy as dollars; treat energy management as financial management and integrate it with your existing financial management and accounting system."
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