Written by: Lisa Clifton, Senior Client Data Manager
WHAT IS IT?
EPA’s ENERGY STAR Portfolio Manager (ESPM) is a free online tool used within an energy management program to track energy and water use in buildings, and benchmarking usage against similar properties nationwide. These benchmarks are determined based on the Commercial Buildings Energy Consumption Survey (CBECS) database.
“Portfolio” refers to the ability to track and compare multiple properties, such as all the campuses in a school district, or all the office buildings or retail stores managed by one company. Users enter monthly utility bill usage and cost data into ESPM; some utility companies will also push monthly data into ESPM upon request.
Certain building types, such as K-12 schools, offices and retail stores, receive an ENERGY STAR Score of 1-100 and may be eligible for national recognition by achieving a score of 75 or above.
WHY SHOULD YOU USE IT?
ESPM is great for gauging how energy efficient your building is compared to similar type buildings in locations with similar climates.
Utility bill data is normalized to a calendar month, and adjustments are made for things like gross floor area, number of staff, operating hours, number of computers, etc. and, making it easy to compare “apples with apples”.
ESPM also provides a single number for each property so it’s easy to compare properties and track whether your annual energy use is increasing or decreasing over time.
WHAT TYPES OF ENERGY DOES IT TRACK?
Your building’s “number” includes all building energy sources – grid electric, solar electric, natural gas, wind, etc. It’s also possible to generate and download reports that include metrics like annual grid electric usage or annual grid electric cost/square foot.
ESPM also calculates the impact of your energy usage on greenhouse gas (GHG) emissions, which contribute to climate change, by accounting for the GHG emission rates of various energy sources. For example, solar electric has lower GHG emissions than grid electric, which is typically produced by burning fossil fuels such as coal or natural gas. GHG emission rates are therefore specific to every utility service provider.
A range of energy-related statistics are available for comparing properties to each other and over time, including weather-normalized energy usage based on 30-year average weather conditions for your area.
WHAT ESPM DOES NOT TRACK.
ESPM is primarily designed for benchmarking and reducing total energy usage and GHG emissions, not for troubleshooting individual utility accounts or managing utility costs.
ESPM doesn’t track solar costs, such as monthly solar lease payments, undercounting the total paid for electricity. Reporting and graphing functions are all annualized – scores are based on a rolling 12 calendar month period. While you can generate reports comparing this year to a previous year, it is not possible to compare this month or quarter to a previous month or quarter.
Graphing tools are very basic, and designed for situations where one building is tied to one electric and one gas account, for example, a stand-alone office building or retail store. In contrast, a hotel, higher education or K-12 school campus may have several buildings and multiple electric and/or gas accounts, and often lack 1:1 correlation between building and account.
Reporting functions are limited and focus on total usage rather than on individual accounts. The data can be downloaded into Excel for manual analysis, however this type of analysis and troubleshooting requires time, effort and expertise.
ESPM does not collect any information on electric demand (KW) a growing source of cost on utility bills.
ENERGY STAR Portfolio Manager is a great tool for benchmarking your energy usage against similar buildings nationwide, for comparing the performance of properties in your portfolio, and for tracking progress as you work to reduce energy use over time. However, it lacks the necessary functionality to be a true utility management, sole energy management tool and troubleshooting tool.
If you would like assistance analyzing your current energy management program or have questions on where to begin, please contact us.