Data Acquisition: The Gateway to Energy Monitoring and Efficiency of Existing Buildings

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1 Data Acquisition: The Gateway to Energy Monitoring and Efficiency of Existing Buildings By Rick Schear, Product Manager, Connectivity and Communications, Eaton Corp. and John White, Director, Energy Management and Sustainability Solutions, Eaton Corp. By implementing a data acquisition solution to monitor and determine energy efficiency, facilities can save money as well as become more sustainable. The ability to acquire and manipulate data is the key to implementing a benchmarking plan to measure and verify energy usage to understand the impact of energy saving initiatives. This capability can enable existing buildings to obtain the Environmental Protection Agency s ENERGY STAR label and new buildings to earn Leadership in Energy and Environmental Design (LEED) credits through the U.S. Green Buildings Council. ENERGY STAR is a joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy designed to help building owners save money and protect the environment through energy efficient practices. The program offers tools and resources to strategize and quantify improvements in energy performance. Its free online tools help assess performance, set goals, create and implement action plans, and evaluate progress. To calculate an Energy Star rating for existing buildings, a minimum of 12 months of utility data plus basic building information is input Sample report from Portfolio Manager source into a free online tool called Portfolio Manager. (See for more information.) PU E March 2012

2 Page 2 of 6 Often those who are reviewing existing building infrastructures and looking for opportunities to make them more energy efficient are unaware that it is essential to develop a benchmarking plan, utilize equipment and tools to implement a strategy for collecting the data needed to develop a plan to achieve established goals. While utility bills show building owners how much power they are buying, they do not reflect how much energy is being used. By understanding the value of benchmarking and how an easy to use, economical data acquisition tool can streamline their ability to use data, building Steps in developing a baseline/benchmark owners can gain the insight into how to Decide on boundaries implement a proven energy monitoring and Plant, multiple plants, entire company measurement solution for improving energy U.S. and global operations Manufacturing operations or total operations efficiency and earning the ENERGY STAR label. Choose a baseline year Establish base year (Year 0) or use existing Benchmarking baseline Benchmarking enables organizations to see how and where they use energy, as well as Gather energy use data Energy use data by fuel source, device what factors drive its use. This information Determine primary and site energy including helps identify key metrics for assessing renewable power performance, establishing baselines and setting energy performance goals. Decide on product grouping and units of output Identify product groups & units of output (Year 0) Benchmarking, which is dependent on data Account for changes in product mix (Year 1-10) acquisition capability, can be internal or external. With internal benchmarking an Calculate energy intensity Baseline energy intensity (Year 0) organization can compare the energy use at a Determine change in energy intensity for building or group of buildings to that of others subsequent years (Year 1-10) in that organization. An organization can use the results to compare energy performance Track and report progress Report select data to management (Year 1-10) among buildings, to identify buildings with the Adjust baseline energy use (Year 1-10) greatest potential for improvement, to track performance over time, to identify best Adopted from: Steps to Develop a Baseline: A Guide to practices at individual sites that can be Developing an Energy Use and Energy Intensity Baseline and the Reporting Requirements for the Save Energy Now replicated, and to increase management s LEADER Pledge, U.S. Department of Energy website; understanding of how to analyze and interpret derbaselinestepsguideline.pdf energy data.

3 Page 3 of 6 External benchmarking enables buildings to be compared to other, similar buildings. The results can be used to assess performance relative to peers in the same sector or industry and across other sectors and industries, to compare the energy performance of facilities against a national performance rating, to track performance against industry or sector performance levels, to identify new best practices for improving building performance, and to increase understanding of how to analyze and evaluate energy performance. Benchmarking may be either quantitative or qualitative. In a quantitative benchmarking process, required for establishing an energy management plan, numerical measures of performance are compared. These numbers may be looked at in a historical context such as how the building s performance has changed over time or in an industrial context such as how a building compares to a peer group of buildings. Data Acquisition While metering provides the raw data for energy measurement and profiling, data collection is only the front end of the benchmarking process. Unless raw data can be exported and analyzed, it has limited practical value. Only when data has been collected and converted into useful information for developing strategies for reducing energy expenses, using energy resources more efficiently and improving operating costs does it become an asset. A key to mining the data that is readily available from meters and input/output devices is to implement a cost effective solution that provides the ability to collect and store historical data that is easily accessible, for example via the Internet. This makes it possible for data on energy use, peak demand, time of use metering of water, air, gas, electricity, and steam (WAGES) to be collected and analyzed. It also provides the potential for the measurement and verification of energy initiatives, load comparisons, threshold alarming and notification, multi-site load aggregation, real-time historical monitoring of energy consumption patterns for negotiating lower energy rates, and identifying errors in utility bills that might otherwise have gone unnoticed. Unfortunately, while many facilities across the United States have implemented energy savings programs, they failed to establish a benchmark at the beginning of the process or collect and analyze data to determine energy savings from their efforts, as evidenced by a recently released report from the Government Accountability Office (GAO) Data shortfalls make tracking efficiency grants a tough slog, GAO, Monday, April 11, The issue here is two-fold, recipients of grants for energy-savings projects must complete complicated forms including hours worked on the project funded by grant funds and actual energy data. When it came to data collection for these Department of Energy funded projects, the report found:

4 Page 4 of 6 determining whether recipients are meeting the energy-saving goals in the Recovery Act is difficult, the GAO report found, since many projects won't result in efficiencies until they are complete. Instead, recipients estimate the savings of projects such as powering a city park with solar panels or replacing a convention center's light fixtures with lightemitting diode bulbs. They do not collect actual data. Because actual energy-savings data are often unavailable, DOE must rely on estimates," GAO analysts wrote. "DOE takes some steps to assess the reasonableness of energy-related estimates, but without knowing which methodology or tool recipients used, it is difficult to do such an assessment. Cost Effective Solution In the past few years, several companies have developed data acquisition tools, at various cost points. By implementing a solution with a low-cost energy meter and data acquisition tool, the situation described by the GAO could have been avoided. While many companies market a range of power quality and energy meters with Ethernet-ready connections, these meters might prove too expensive for many projects. However, a wide-range of energy meters at a lower price point without direct Ethernet connectivity is also available. Unfortunately, without a data collection and storage tool, collecting and storing data from these meters can be a tedious process. Eaton Corporation is one company that has filled the gap. Its data acquisition product, the Power Xpert Gateway 200E (PXG 200E), allows those striving to improve the energy efficiency of existing buildings to implement an economical solution for measuring and improving energy efficiency. Power Xpert Gateway 200E Device Page

5 Page 5 of 6 The PXG 200E provides users with the ability to remotely monitor their energy consumption. The PXG 200E used with revenue-grade metering acquires revenue-accurate interval data and makes it available for the real-time viewing as well as recording the key energy values in a five minute fixed interval log file. The PXG 200E collects the data from individual meters, which can be viewed and analyzed via embedded web pages. The PXG 200E has its own web server and web pages, plus the connected meters have their individual web pages. The status of all connected devices is available on a bus page making checking their health and performance quick and easy. Not only is information easily accessible through any web browser, which enables remote monitoring, but there are also additional features to speed installation and lower integration costs through plug-and-play connectivity. More specifically, it acquires and logs data from up to 64 serially communicating meters and input/output devices via INCOM and Modbus RTU connected devices in fixed five-minute intervals. Data from downstream devices is time stamped and stored in non-volatile memory. The supported parameter values can be passed on to existing or new management software packages. Using Modbus TCP, users can view, record, and monitor in their Building Management System or, using SNMP, users can view, record, and monitor in their Network Management System (NMS). Using the PXG 200E s user interface via Ethernet, collected data can be pushed or pulled via HTTP/HTTPS or any Ethernet-based building management system via Modbus TCP or network management system via SNMPv.1. In addition, the interval log file can be exported to Microsoft Excel to generate a report or graph for further manipulation and recording. The PXG 200E also functions with a Digital Input Module to monitor water, air, gas, electric, and steam (WAGES) data acquisition, logging and real-time value display. Tools like Eaton Corporation s Power Xpert Energy Viewer (PXEV), a free downloadable tool, provide expanded views into energy Eaton s Power Xpert Energy Viewer s ( summary report.

6 Page 6 of 6 benchmarking, usage, and savings. This tool, provides PXG 200E users with a way to gather the key energy parameters they are concerned with and display them in a simple tabular and graph report. The PXEV allows users to select up to four devices at a time and any of the interval logged data points to compare the downstream devices energy parameters to other energy parameters or other devices from the same time variable (day, week, month). Proven Solutions Data acquisition, which is imperative for ongoing energy monitoring and increasing usage efficiency, can be a low cost investment that can yield substantial returns. With products like the PXG 200E, products, building owners can save energy, protect the environment, and earn the ENERGY STAR label with proven, cost effective equipment and solutions.