Monday, March 9, 2015

Energy Efficiency and Benchmarking

My experience with energy efficiency has been an interesting one. It all started back in 2006 while going to school and working as an usher for an historic movie theater in the Bay Area, where I would spend time every week finding and replacing burnt out light bulbs with a like-for-like replacement. I didn’t have a degree in mechanical or electrical engineering, but I knew that those incandescent bulbs needed to go. Unfortunately at the time, market forces weren’t strong enough to make LED or cold cathode fluorescent lights, those dimmable CFL-like bulbs, cost effective. I still have the very basic walkthrough audit that I did as part of an Urban Ecology course hosted at the EPA.
One of the slides I produced for my work and a class at the EPA office.
Now fast forward several years to my work here at SJVCEO.  One important part of my job is to benchmark the energy consumption of municipalities, both city and county governments, throughout the San Joaquin Valley.  Energy benchmarking consists of gathering a building’s energy consumption, along with a few simple variable inputs like number of employees, computers and operating hours, and compares it against a national survey of buildings.  Thanks to formulas and software, energy benchmarking is pretty straightforward--you plug in the numbers and the system does the rest.  And with California investor-owned utilities stepping up with their own systems to complement energy benchmarking, you’ll never have to enter in billing information, removing the possibility of sore hands from data entry, and headaches because of incorrect entries.

With businesses occupying a single building, benchmarking isn’t very difficult to do.  I even benchmarked my house from start to finish in about 10 minutes!  But imagine a business occupying 10 buildings, or multiple businesses occupying a 10-story building, and things get a little more complicated.  With cities, it’s just a matter of imagining hundreds, even thousands of “buildings.”

With local governments, we use energy benchmarking not only to compare against a national average, but also an easy (and more importantly, free) energy management system.  Using EPA’s ENERGY STAR Portfolio Manager, a city can input every energy account it has and be able to analyze consumption every month.  You can easily see, using historical energy usage, how much previous energy conservation projects have made an impact, and whether or not energy consumption is drifting excessively.  It’s even able to normalize energy consumption based on weather, so you’ll be able to compare energy performance in a hot summer year versus a moderate summer year.

But why benchmarking?

Benchmarking is a cost-effective approach to prioritizing building audits and retrofits.  Why get a costly audit done if you don’t know how your buildings stack up?  If you were concerned that your car may not be getting the gas mileage you expect, wouldn’t you check to see how it stacks up?

The images above refer to a building, built in 2002 but too small to receive an ENERGY STAR Score. It has been consuming less energy every year—normalizing for weather—but it’s also consuming more energy per square foot than its peers do. If other buildings in the portfolio have smaller “drifts” from the median, then this customer may want to prioritize work on this building first, assuming that there have been no changes in operation that could account for the change in consumption.

Imagine being able to pull a report monthly, and seeing how energy consumption is changing, along with the weather. If something is drawing too much energy in a short amount of time, you'll have time to address the issue and potentially save a lot of energy and money.  And when you measure your energy usage, you can manage your energy usage.

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