By Nicole Imeson, P.L.(Eng.)
An energy management information system (EMIS) is a comprehensive computer-based program to monitor, control and optimize energy usage. It differs from a building automation system (BAS) because it focuses on energy, whereas a BAS focuses on system operation and thermal comfort. An EMIS is a tool to allow the operations team to make more informed decisions in a timely manner. However, this information is only part of the equation, and action must be taken as well. Identifying broken equipment or failed sequences is the easy part, having someone in-house to fix the broken item is the complicated part. “Without the operations team, you're really just investing in a tool to tell you all the problems you have” told Russell Bock, manager of smart building services at DB Technologies.
Since engagement is key to the success of an EMIS, making the process as simple as possible is essential. Depending on the capabilities of the building and systems, the EMIS is an add-on to complement the features of the BAS without creating the additional hassle of logging into separate systems. Implementing an EMIS “needs to be collaborative with the operations team. Even though sustainability groups are bringing this in for operations to implement, a lot of operations teams see this as replacing them. However, they're experts in their building, and their experience of running the building is not replaceable. This is a tool to help them be more efficient,” explained Bock.
Several factors determine whether a building could benefit from an EMIS. Assessing the energy usage, building complexity, and quality of systems and operations is a great first step. The potential return on investment (ROI) — ideally one to two years — comparing EMIS installation costs and estimated savings should also be reviewed. “Clients with single buildings having complicated systems, such as hospitals and airports, have very different challenges compared to other clients with large portfolios of simple buildings. But the need for centralized data, the ability to analyze data, and the value proposition are the same,” noted Bock. While a simple building itself may not benefit from an EMIS, when an owner has a portfolio of simple buildings, an EMIS helps the energy manager allocate resources regionally to focus on different energy conservation measures (ECMs) and savings targets.
An EMIS typically looks at the energy usage of HVAC systems, lighting, and metering as a baseline. Additional systems can be added, such as elevators and escalators or security and occupancy counting. When submetering is not available or cost-prohibitive to install, whole-building metering is a good start. Newer equipment often has metering capabilities included and available through BACnet connections —for example, data points for energy usage, run times, and output performance of chillers, VFDs, and boilers can be brought into the EMIS through BACnet from the equipment.
Once the data is collected, the energy use intensity (EUI) and thermal comfort are assessed. The EUI is used to determine if energy consumption is above average compared to buildings in the same market sector, which signifies energy-related cost savings potential. The September and October checklist articles explored EUI and thermal comfort when it comes to energy analysis and implementing various ECMs.
When operators and owners are only focused on energy usage, they may start to manually intervene in system operations. Similarly, when the ECMs are viewed in silos rather than a holistic approach to energy management, the building function can shift from the original basis of design. While this can save energy for the specific ECM, it may increase the energy usage of the whole building. For example, turning off an air handler in the winter to save energy will result in occupant complaints about thermal comfort and building pressurization or other equipment working just as hard or harder to maintain the heating setpoint. In addition, the overreaction to thermal comfort complaints takes time and money to resolve and can have massive energy costs.
When it comes to energy management and implementing an EMIS, start small, fail small, and then build up. For an energy management project to be successful, the data is analyzed and leveraged as a tool to act. In a large project with a large amount of data and several ECMs being implemented at the same time, the information and amount of change become overwhelming to all parties involved, and the change is not sustainable. “You're better off implementing smaller, reasonable, and digestible things and then building on it. We tend to see more success because you're moving people along a continuum rather than trying to make extensive changes,” revealed Bock.
Managing technology changes can be a challenge for EMIS’ when comparing the lifecycle of a building in relation to the turnover of new technology. Owners are looking to amortize a piece of equipment over 25 years, whereas the technology world turns over new products every 12-18 months. Adding in the mentality and speed with which people change behaviors, it can be really challenging to implement sustainable change. However, energy management is meant to be a system of continuous improvement. If data is still available and analyzed, and the system is expandible to add new data sources in the future, improvements can be continuously made without reinventing the wheel when a piece of new technology is available.
EMIS can also offer a mechanism for a feedback loop between the construction and operations teams, both of which have very different mandates. The construction mandate is to deliver a project on schedule and budget, and the operation's mandate is to run the building. However, these two businesses often operate separately in an organization. If the operations team discovers issues within the building and does not notify the construction team, the issues cannot be corrected and implemented into the next design. While digital twins and EMIS can help, this is also a key benefit of engaging a commissioning provider (CxP) on every project. CxPs are typically the only party involved in all aspects of the building’s lifecycle. They are the first consultants hired by the owner and follow the building through construction into operations, ongoing commissioning, and existing building commissioning. This offers them unique insight into the limitations of building design with an opportunity to implement changes for future projects.
EMIS’ don’t need to be complex to add value to a building. By starting small with the existing equipment, tools, and systems available, the operations team can leverage the data to start analyzing and modifying operations to reduce energy usage while maintaining thermal comfort. Once the operations team has exhausted the energy usage and thermal comfort measures based on the available information, they can look at expanding the EMIS to include additional data points and metrics.