Are your energy bills hiding energy savings?

Photo by Flickr user dougwoods

Take a look at the bills below for a small commercial building. Below the monthly cost, you can see the year-on-year change. The July and August bills saw nice dips, followed by a big 17% jump up in September.

bills-no-ops

This building installed a large controls project in June which they expected to save about 8% of total energy spend. This is every facility manager’s worst nightmare — a large investment in energy efficiency followed by an increase in the utility bill! My stomach churns just thinking about the nasty call from the asset manager.

Of course, a variety of factors influence bills and the change from year to year (or from budgeted to actual):

  • Weather: Especially because of volatility in demand charges, costs are highly responsive to hot weather.
  • Rate: Utilities tend to raise rates year after year, and the intersection of time-of-use effects with individual energy use patterns results in unpredictable changes to your bill.
  • Calendar: Bill period length can vary by 10% or more, and the exact number of weekends and holidays in a billing period show up in your costs.
  • Operations: Once all the other sources of variation have been accounted for, operations is what’s left over. This category includes everything from occupancy effects to events to equipment failures.

The beauty of an energy model is that it can isolate the signal from the noise, breaking down variance according to source. The bill data up above is collected and presented in Gridium’s Billcast product, which also performs variance analysis. Billcast automatically corrects for the uncontrollable (weather, rate, calendar), showing exactly what portion of the year-on-year variance should be ascribed to operations:

bills-ops
Phew! The nightmare is now over. After correcting for weather, rate and calendar, the project is saving even more than expected. Join me in feeling the relaxation flow though your body as you calmly drop the numbers into an email to your asset manager.

Variance reporting is part of our Billcast product and quickly becoming a most favorite feature among customers.

About Tom Arnold

Tom Arnold is co-founder and CEO of Gridium. Prior to Gridium, Tom Arnold was the Vice President of Energy Efficiency at EnerNOC, and cofounder at TerraPass. Tom has an MBA from the Wharton School of Business at the University of Pennsylvania and a BA in Economics from Dartmouth College. When he isn't thinking about the future of buildings, he enjoys riding his bike and chasing after his two daughters.

0 replies on “Are your energy bills hiding energy savings?”

You may also be interested in...

4CP Season 2024: A Look Back & Lessons Learned
4CP Season 2024: A Look Back & Lessons Learned

How did our new 4CP alerting service help Texas building operators and owners get ahead of costly demand charges this summer? Check out the results and learnings from another active, heatwave-y 4CP season in ERCOT territory.

Boosting Building Performance on a Budget: 4 Takeaways from BOMA 2024
Boosting Building Performance on a Budget: 4 Takeaways from...

Earlier this month, the Building Owners and Managers Association (BOMA) International hosted its 2024 conference in Philadelphia, PA. Here are a few of our takeaways from the event for those of you who couldn’t make it out! Focus on the…