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Services & Maintenance: Energy Measurement And Verification

Written by Services and Maintenance Contributor. Posted in Energy, In-Depth Articles, Magazine, Services & Maintenance, Sustainability

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Published on March 18, 2009 with No Comments

By John Schinter

Published in the March 2009 issue of Today’s Facility Manager

A facility management (FM) department operating a corporate portfolio of buildings in the U.S. spent nearly $30 million on energy costs in 2005. This organization was able to reduce its energy usage by more than 7% in the three years that followed, helping to keep costs stable at a time when some regions were seeing 20% rate hikes.

facility management energy measurement verification
Today, this organization is on track to meet its five year goal of reducing greenhouse gas emissions by 15% through the implementation of additional portfolio energy management strategies. It also hopes to establish an increased commitment to renewable energy.

The actions taken to achieve these results involved ordinary energy management tactics, but the case illustrates the importance of measurement and verification (M&V) in two ways. First, the fact that energy and environmental data across a large portfolio can be accurately measured and reported at all is unusual. More important, the sophisticated tracking and reporting system that captured the data also helped the energy management team maximize results by quickly identifying and correcting the most serious inefficiencies.

M&V Guidelines And Resources

There are many ways to measure and verify energy efficiency. Engineers generally equate M&V with the Efficiency Valuation Organization’s (EVO) International Performance Measurement & Verification Protocol (IPMVP) as a way to measure systems in isolation or to conduct whole building comparisons (see sidebar for more on EVO).

Meanwhile, the ENERGY STAR Portfolio Manager from the U.S. Environmental Protection Agency (EPA) has gained wide acceptance as an effective way to identify baseline efficiency and to quantify degrees of progress over time. ASHRAE also has standards for determining a baseline.

The U.S. Green Building Council’s (USGBC) LEED building rating system draws on IPMVP, ENERGY STAR, and ASHRAE for various standards of measurement. However, the most recent LEED for Existing Buildings-Operations & Maintenance (EBOM) standard (which replaced the Existing Buildings standard) does not directly give facility managers (fms) credit for M&V follow through. Buildings that have metering installed do get credit under LEED-EBOM, and fms are expected to have a plan for monitoring the data, but whether the data is collected and used productively is an open question.

Regarding new buildings, in March 2008, the New Buildings Institute based in Vancouver, WA concluded a study funded by the USGBC, with support from the EPA, on the energy performance of LEED for New Construction (NC), version 2 buildings. Of the 552 LEED certified buildings invited to participate in the study, management in 250 of those was willing to supply information, but only 121 could supply the energy usage data typically found on monthly bills.facility management energy New Buildings Institute

Moreover, even though about 40 of the participating buildings had achieved the LEED credits that mandated M&V for at least one year of operation, only four could provide actual M&V data. (The chart shown here is from the study and shows the breakdown of participants (buildings) by their available metrics.)

In short, an fm in a LEED certified building who can maintain a good ENERGY STAR rating may have no motivation to monitor energy usage. However, fms (corporate, especially) should be strongly motivated to do so, whether or not their buildings are recognized by LEED or ENERGY STAR. Not only are these professionals under pressure to lower costs, but corporations increasingly need to report reductions in carbon emissions—a large percentage of which may come from their facility operations. Here the M&V challenge is not limited to a single site, but to every building in the company’s portfolio.

Hence, there are five levels of granularity in M&V, from the portfolio, down to buildings, then to systems and machines, and, finally, components. Can any M&V system effectively encompass all these levels? The answer is yes, it can, and it is being done at some of the largest facility portfolios in the U.S. In fact, the larger the portfolio, the easier it is in some ways to identify opportunities for improvement.

The International Performance Measurement
And Verification Protocol (IPMVP)

Compiled from information provided by the Efficiency Valuation Organization

The Efficiency Valuation Organization (EVO) is an international, non-profit organization focused on creating measurement and verification (M&V) tools to foster increased efficiency in energy (and water) use. The EVO asserts that in order for efficiency to be considered a reliable resource, its energy savings, including the persistence of savings, must be verifiable, and project transaction costs must be kept to reasonable levels. If energy efficiency is to realize its full potential, EVO’s stance is that facility management (FM) professionals, service companies, consultants, contractors, and financiers need to adopt common technical, financial, and legal standards that guide the M&V of savings.

Currently, the EVO-owned International Performance Measurement and Verification Protocol (IPMVP) is a leading international standard in M&V protocols. The IPMVP is a widely referenced framework for measuring energy or water savings. It is especially used in energy performance contracts where savings must be reported to a client and may form the basis of a payment to an energy services company (ESCO). M&V activities can include site surveys, metering of energy or water flow, monitoring of independent variables, calculation, and reporting.

Definitions
The IPMVP includes numerous definitions for users to reference in their M&V efforts. Following are several terms mentioned in this article. A full list can be found in the IPMVP literature on the EVO’s Web site (see end of article).

Baseline Period. The period of time chosen to represent operation of the facility or system before implementation of an ECM. This period may be as short as the time required for an instantaneous measurement of a constant quantity, or long enough to reflect one full operating cycle of a system or facility with variable operations.

Energy Conservation Measure (ECM).
An activity or set of activities designed to increase the energy efficiency of a facility, system, or piece of equipment. ECMs may also conserve energy without changing efficiency.

Several ECM’s may be carried out in a facility at one time, each with a different thrust. An ECM may involve one or more: physical changes to facility equipment; revisions to operating and maintenance procedures; software changes; or new means of training or managing users of the space or operations and maintenance staff. An ECM may be applied as a retrofit to an existing system or facility, or as a modification to a design before construction of a new system or facility.

Measurement Boundary.
A notional boundary drawn around equipment and/or systems to segregate those which are relevant to savings determination from those which are not. All energy uses of equipment or systems within the measurement boundary must be measured or estimated, whether the energy uses are within the boundary or not.

Savings. The reduction in energy use or cost. Physical savings may be expressed as avoided energy use or normalized savings. Monetary savings may be expressed analogously as “cost avoidance” or “normalized cost savings.” Savings, as used in IPMVP, are not the simple difference between baseline and reporting period utility bills or metered quantities.

Measurable Action
The IPMVP provides four options (A, B, C, D) for FM professionals to determine savings. Choosing which option to use for M&V of a project involves a number of considerations including the location of the measurement boundary. For instance, option C or D may be favored if the facility manager (fm) wishes to determine savings at the facility level. However, if only the performance of an energy conservation measure (ECM) itself is of concern, a retrofit isolation technique may be more suitable (option A, B, or D).

Following are brief explanations of each of the four options that can be used to determine energy savings, as contained in the 2007 edition/Volume 1 of the IPMVP from EVO.

A. Retrofit Isolation: Key Parameter Measurement.
Savings are determined by field measurement of the key performance parameter(s) which define the energy use of the ECM’s affected system(s) and/or the success of the project. Measurement frequency ranges from short-term to continuous, depending on the expected variations in the measured parameter and the length of the reporting period.

An example of an application would be a lighting retrofit where power draw is the key performance parameter that is measured periodically. Users estimate operating hours of the lights based on building schedules and occupant behavior.

B. Retrofit Isolation: All Parameter Measurement.
Savings are determined by field measurement of the energy use of the ECM-affected system. Measurement frequency ranges from short-term to continuous, depending on the expected variations in the savings and the length of the reporting period.

An example of when this approach would be used is in the application of a variable-speed drive and controls to a motor to adjust pump flow. Users measure electric power with a kW meter installed on the electrical supply to the motor, which reads the power every minute. In the baseline period, this meter is in place for a week to verify constant loading. The meter is in place throughout the reporting period to track variations in power use.

C. Whole Facility.
Savings are determined by measuring energy use at the whole facility or sub-facility level. Continuous measurements of the entire facility’s energy use are taken throughout the reporting period.

A typical application would be a multifaceted energy management program affecting many systems in a facility. Energy use is measured with the gas and electric utility meters for a 12 month baseline period and throughout the reporting period.

D. Calibrated Simulation.
Savings are determined through simulation of the energy use of the whole facility or of a sub-facility. Simulation routines are demonstrated to model actual energy performance measured in the facility adequately. (This option usually requires considerable skill in calibrated simulation.)

This approach is typically used in a multifaceted energy management program affecting many systems in a facility but where no meter existed in the baseline period. Energy use measurements, after installation of gas and electric meters, are used to calibrate a simulation.  Baseline energy use, determined using the calibrated simulation, is compared to a simulation of reporting period energy use.

The IPMVP is currently in its fourth edition and can be downloaded at www.evo-world.org under the Products & Services tab. IPMVP is prepared in three Volumes: Volume I, Concepts and Options for Determining Energy and Water Savings; Volume II, Indoor Environmental Quality (IEQ) Issues; and Volume III contains specific application guidance manuals for Volume I. The EVO has offices based in Washington, DC. 

 

Drilling Down As Far As Needed

The key to successful M&V is to gather information on each building on a timely basis in a program that automatically translates the data into a series of on-demand charts and graphs. Visually expressed, the relevant data can be viewed on one computer screen—an interface known as a dashboard—for any type of information, time period, and level of stakeholder, from concise overviews for corporate and business unit leaders to detailed single facility assessments for fms. The dashboard data also facilitates accounting procedures for the organization by integrating with bill processing and payment firms for automatic uploading of information.

The dashboard user follows a practice known as “management by exception,” which, in simple terms, means looking for data that is out of sync.

A dashboard makes this easy: when one bar in a chart is longer or shorter than the others, or when a line on a graph suddenly lurches, it is worth further investigation to determine what has happened. With an interactive system, investigation may be a matter of clicking on a specific facility or time period to drill down to the next level of information or deeper, if necessary.

An example: The dashboard for a company with a dozen similar plants shows that one location has significantly higher electric bills than the others after adjusting for climate. Clicking on a year over year history of that facility’s bills as well as data over the previous three months, it appears that the increase has occurred in the past 60 days. The FM department reports identify a small number of projects during that time that could account for the change; by analyzing the meter data from systems relating to those projects, the FM team is quickly able to isolate the piece of equipment that was installed incorrectly.

Note in this example that the centralized dashboard data need not include every component or even every piece of equipment in the facility. The centralized energy management needs only enough measurement data to determine anomalies. Once a problem has been detected, the investigative work is at least partly in the hands of the FM team at the site, which can look at meter data and interview team members to diagnose the problem and take corrective action.

Such a system is the fastest and most cost-effective way to achieve energy savings, because it enables the FM team to identify priorities and develop a cost-benefit equation for improvements. An fm operating an old, inefficient system might make the case to upper management that an upgrade is necessary, but that case will be much stronger when the fm can show the cost differential between that facility and others like it.

The ability to compare quickly the running cost of inefficiency with the one time cost of replacement facilitates the decision making process and ultimately leads to a program that balances energy efficiency and cost effectiveness. In this way, M&V is not just an academic exercise or a rote process to ensure a facility’s LEED or ENERGY STAR certification, but it becomes an essential part of an energy management program.

As president of energy and sustainability services at Jones Lang LaSalle (JLL), Schinter directs teams with the goals of reducing energy use in facilities, saving money, and avoiding greenhouse gas emissions. He has worked with JLL teams on 116 completed or current LEED projects totaling more than 35 million square feet worldwide. Schinter was named 2008 Energy Engineer of the Year by the Association of Energy Engineers (AEE). He can be reached at john.schinter@am.jll.com.

(Image credits: Photo (JupiterImages); Chart (New Buildings Institute))

To download a copy of the New Buildings Institute report mentioned in this article, visit www.newbuildings.org/research.htm and go to “LEED Energy Performance Project.” 

About Services and Maintenance Contributor

Facility managers are often required to take a reactionary approach when it comes to problem solving. This column provides proactive, “how to” solutions to some of the ongoing issues. For additional Services & Maintenance articles, click this link.

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