Energy Management Systems (EMS) vs Building Management Systems (BMS): What You Should Know

An EMS and a BMS serve two different functions but can work together in a building, here's what you should know about them and their purposes.

An EMS and a BMS serve two different functions but can work together in a building, here's what you should know about them and their purposes. As buildings continue to become more technologically advanced and energy efficient, two systems are often used to control and optimize energy usage: Energy Management Systems (EMS) and Building Management Systems (BMS). While these terms are sometimes used interchangeably, they refer to two distinct systems with different functions and purposes.

With the average commercial building wasting 30% of the energy it consumes, energy efficiency in the building sector is on the minds of many. In this blog, we will discuss some of the common terms we run into when discussing improving and optimizing building efficiency, and discuss the differences between EMS and BMS, their key features and benefits, and how they can be used to improve energy efficiency and reduce costs in commercial and industrial buildings.

Whether you are a building owner, facilities manager, or energy professional, understanding these systems is essential for optimizing energy usage and achieving sustainability goals.

What is a Building Management System?

A Building Management System (BMS) is a computer-based centralized control system used to manage and monitor a building's mechanical, electrical, and plumbing systems (MEP). The BMS is responsible for controlling heating, ventilation, air conditioning (HVAC), lighting, security, and other building systems to ensure they operate efficiently and effectively. BMS technology is an essential component of modern building automation systems and is widely used in commercial, industrial, and institutional buildings.

A BMS's primary function is to ensure the electrical and mechanical systems in a building are operating effectively and allow facility managers and chief engineers to centralize and automate the control of the building's various systems. 

Some benefits of a BMS include:

  • The ability to control multiple systems in a building
  • Being able to monitor the performance of various systems
  • Improved maintenance schedules which can extend equipment lifetime
  • Allowing automation in the systems the BMS monitors 
  • The ability to provide consistent building comfort automatically 

Are a BMS and a BAS the Same Thing? 

A Building Management System is also known as a Building Automation System (BAS) and both terms tend to be used interchangeably. This system is a distributed control system that involves multiple systems and can sometimes help in the automation of certain controls or settings. 

What is an Energy Management System? 

An Energy Management System is a specialized software system that is used to monitor, analyze, and optimize a building's energy usage and power distribution. EMS technology is specifically designed to measure and manage energy usage across a building's systems and operations.

An EMS collects data from various sources, including the BMS, system equipment, utility meters and sensors, and can provide real-time data insights into energy usage patterns, trends, and anomalies. A facilities manager can then use this information to identify areas of inefficiency, diagnose issues, and adjust systems accordingly. 

By automating and optimizing building operations, an EMS can help reduce energy consumption, lower operating costs, and improve occupant comfort and safety.

Do Buildings Need Both an EMS and a BMS? 

As building energy management continues to grow in significance, building owners may be wondering if their buildings need both an EMS and a BMS running in them. 

While a BMS focuses on managing and controlling the system in a centralized location, an EMS is specifically going to allow for optimizing efficiency in a building. By combining both systems, facility managers and building operators can obtain a comprehensive view of their building's performance, identify areas of inefficiency, and take corrective actions. 

For example, a BMS can help identify the most energy-consuming equipment, and EMS can provide insights into energy usage patterns and trends across the building systems. By combining these insights, facility managers can optimize energy usage and reduce pollution contribution. 

Whether your building needs both systems will rely on what goals you have in place, such as being part of a community making an effort to reduce building CO2 emissions such as cities like New York City and Seattle that are implementing carbon drawdown laws. 

Energy efficiency goals can be met by implementing overlaying systems and utilizing other technology aids to assist in reducing pollution and energy consumption. 

Using New Technology With Existing Systems

With ambitious goals to reduce energy waste around the world, it's clear that Building Automation Systems and Energy Management Systems will provide energy professionals with the information necessary to strategize ways toward efficiency. Lucky for building operators, there are a variety of options for automation and optimization, and smart building technology such as machine learning and artificial intelligence tools will be at the helm of providing these abilities. 

There is a lot that can be done with equipment data, and while a BMS and EMS can control and collect it, you'll need more technology in the mix such as ML-powered algorithms that can optimize energy efficiency and provide energy professionals with the information they need to make decisions. Tools such as these can communicate with a building's BMS and EMS to provide additional energy efficiency measures. 

Venturing into the world of building energy requires some specific knowledge. If you're interested in learning more about these systems and how machine learning can support them, schedule a call and chat with someone on our team.

Ruth Favela
Ruth Favela
March 6, 2023