Managing power through networked electrical systems
Engineers should consider the benefits of networking electrical systems—monitoring and controlling power, its usage, and how it affects system reliability.
- Understand the importance of measurement and verification.
- Know the available monitoring solutions.
- Identify the criteria for integrating electrical networking solutions into facility electrical distribution systems.
In the ever-changing world of technology, at times it seems that marketing a new technology requires either creating new words or stringing old words into new phrases to make it sound new and cutting-edge, or perhaps just confuse the consumer altogether. In fact, it’s hard to imagine a profession that uses more buzzwords and acronyms than the field of engineering and construction. When it comes to networking of electrical systems and power management, there is no shortage of this trendy lingo: “digital energy networks” that monitor “distributed energy resources” tied to the “virtual power plants,” or the “detailed energy survey (DES)” for the “energy conservation measure (ECM)” and its interface with the “building management system (BMS)”—shall I go on? But what does it all mean as it relates to the networking of systems and overall power management?
In recent years, billions of dollars have been spent by electrical utility companies on Smart Grid technologies. A Smart Grid consists of two-way digital communications between energy users (facilities) and the utility’s network operation center. Capturing this smart technology concept and filtering it much further in to the facility (down to the end-use device) opens up opportunities to better manage overall power, ranging anywhere from an individual facility to a large campus system. BMS have been around for decades, providing the ability to monitor and control HVAC components, and more recently, the BMS may integrate fire, security, and lighting control systems. However, programs such as demand response and other energy management curricula have created a strong motivation to fully integrate what traditional BMS systems have left out. Additional components, such as power generation equipment, UPS, power switching equipment, and other metered loads now want to be part of the same smart system. One of the latest buzz phrases to describe this facility trend is “networked electrical systems.” This concept of a networked electrical system not only includes the electrical system that delivers the electricity, but also encompasses the components that use the electricity.
The facility manager’s struggle
Energy is a major operating expense for most organizations and, according to EnergyStar.gov, can represent 30% of a typical commercial office building’s operational costs (see Figure 1). However, managing energy usage can be a daunting task. The facility manager is often fighting mounting pressure to lower costs while energy prices are on the rise. Additionally, the reliability of that energy supply is declining. The expectation that facility managers “do more with less” presents a challenge even for the seasoned and highly qualified facility managers. The paradigm is that the workforce responsible for overseeing these complex energy systems continues to age. According to the International Facility Management Association (IFMA), in 2011 the average age of a facility manager was 49. And according to the Sloan Center on Aging and Work, it is expected that more than 50% of facility management personnel will retire within the next 10 years. The good news is that in 2011, IFMA also reported that more young people are entering facility management with 9% age 34 or younger. This is up 2% from 4 years prior. However, at that rate, a one-for-one replacement will not be possible, which presents a challenge for the design engineer and end user alike. As codes continue to rapidly change and energy costs continue to rise, the engineer is charged with providing a workable design solution for managing a facility. At the same time, the facility manager is responsible for operating the systems as they were intended with less overall manpower. The need for a connected and monitored system where usage can be tracked and controlled from a central location exists in any facility where power is critical. Facilities such as health care, commercial, industrial manufacturing, governmental, data centers, and higher education are perfect candidates for this technology. Large campus-type facilities are particularly good candidates because they have multiple buildings to monitor. A migration to a centralized management system could be the solution.
Measurement and verification
There are several aspects of networking electrical systems that must be considered. Step No.1 is to correlate the popular management statement as it relates to energy: “You can’t manage what you don’t measure.” Understanding what drives energy usage is the first key to managing it. Interpreting the data and recognizing what to do with them is the next step in successfully implementing changes in the system to provide the desired end result.
The industry term “measurement and verification” (M&V) is a process for quantifying savings determined by an energy conservation measure. Although M&V continues to be an evolving art, various standards and protocols demonstrate best practices. One of the most popular is the U.S. Green Building Council LEED rating system. LEED specifically references the International Performance Measurement and Verification Protocol (IPMVP) Volume III: Concepts and Options for Determining Energy Savings in New Construction. Another popular reference is ASHRAE Guideline 14: Measurement of Energy and Demand Savings.
The IPMVP Volume III protocol states that it was developed to “provide a concise description of the best practice techniques for verifying the energy performance of new construction projects. The objective is to provide clear guidance to professionals seeking to verify energy and demand savings at either component- or whole-building level in new construction.”
ASHRAE Guideline 14 was developed to “provide guidelines for reliably measuring energy and demand savings of commercial equipment.”
Using the available guidelines is an appropriate starting point for the engineer to design a solution that provides the facility manager with the proper tools to manage energy in the facility. These guidelines suggest various starting points based on the level of M&V desired, including performing a DES and planning specific ECMs to include in the design. Prior to implementation, however, it is important to assess the end users’ needs and capabilities when selecting the appropriate monitoring approach.