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Submetering Leads to Better Energy Management

October 23, 2013 | 6 comments

Nothing drives home the value of energy management initiatives like data that proves cost savings and usage reductions.

Submetering can be a cost-effective way to measure actual utility reductions from some of your energy- and water-saving initiatives. Installing submeters allows facilities professionals to separately monitor electricity, gas, water, steam, and other utilities for individual tenants, departments, or pieces of equipment.

A typical submeter monitors a specific utility usage, sending data approximately every 15 minutes to energy management software for analysis. Facilities professionals can then use that data analysis to identify utility savings and usage-reduction opportunities. Submetering can also help building owners and facilities managers:

  • Obtain actual energy and other utility usage information (no estimations or guesses)
  • Analyze the appropriate allocation of costs
  • Measure and verify energy conservation programs and projects
  • Receive immediate feedback on projects to improve building operations and utility usage
  • Identify possible equipment failures and problems (equipment running at night, for example)
  • Offer comparison and benchmarking across similar facilities in a portfolio and over time
  • Detect errors in utility bills by comparing submeter data with the actual bill

Whether it’s owner-occupied or not, almost any commercial or institutional facility can benefit from a submetering strategy. Recently, the 30-story Hyatt Regency Houston decided to install a submetering system to measure energy savings from window film installation.

The hotel was having trouble keeping hotel rooms cool during the day; staff members were also receiving complaints from guests about warm temperatures. Before the hotel decided to invest in a new or upgraded HVAC system, staff members wanted to explore more cost-effective ways to address these issues.

To save energy, reduce HVAC loads, and increase guest comfort levels, the Hyatt Regency Houston decided to install window film in 48 southeast- and southwest-facing rooms. To measure heating and cooling savings, the hotel installed submetering to measures HVAC usage in the 48 rooms with window film, as well as in 48 southeast- and southwest-facing rooms without window film. The data from the submeters confirmed that window film installation reduced cooling energy use by 23%, and heating energy use by 25%. Without submetering, this data wouldn’t have been captured to prove that window film was a cost-effective, energy-saving investment that would provide a quick ROI.

By submetering critical loads, such as HVAC and plug loads, facilities professionals have access to data that will help uncover exactly what’s happening with building operations. And once problems are identified, steps can be implemented to reduce usage in necessary areas of the building or improve operations.

Have you implemented submetering in your facility? Has it helped you break down utility usage?



  1. Robert Mabry
    September 27, 2015

    The benefits of sub-metering also apply to cooling towers or other water cooled equipment. Sewer credits related to evaporation may be available from a local water or sewer utility that will reduce operating costs and also pay for the sub-metering equipment in a very short time. Savings from sewer credits can pay for window film, lighting upgrades, or other energy saving modifications. And sub-metering may also make the building eligible for LEED points.

  2. Anatoli Naoumov
    October 2, 2015

    Energy savings aside, films have contributed in a number of other valuable ways:
    - room comfort -> guest satisfaction -> higher occupancy -> higher profits
    - less calls from unhappy guests -> service has more time to address other needs -> better guest experience -> higher occupancy from happier guests -> additional revenue from other services -> higher profits
    - reduced CO2 emission -> green image -> better market position -> new services: conferences, et al -> higher profits

    This list can be continued. These benefits will ONLY be realised if the benefits are measured. Submetering energy use is just a beginning.

  3. Anatoli Naoumov
    October 2, 2015

    btw, Return On Investment (ROI) is measured in %%, it can be high or low, but can’t be quick.

  4. Vista
    October 5, 2015

    Great feedback, Anatoli. Thanks so much – and we agree!

  5. Vista
    October 5, 2015

    Hi Anatoli … it likely depends on your definition of “quick.” If you receive a full, 100% return on your investment in three or four years as a result of energy savings, many facilities professionals would in fact consider that a fast ROI. Especially when compared to other energy-efficiency projects which may take years longer before they pay for themselves. Hope this offers a better explanation!

  6. Vista
    October 5, 2015

    Robert, you make a great point. Thank you!

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