Building energy management systems BEMS
Building Energy Management Systems (BEMS) are integrated, computerised systems for monitoring and controlling energy-related building services plant and equipment such as heating, ventilation and air conditioning (HVAC) systems, lighting, power systems and so on.
The phrase Building Energy Management Systems is sometimes used interchangeably with Building Management Systems (BMS), however, strictly speaking, Building Management Systems can be used to monitor and control a wide range of building systems, including fire, smoke detection and alarms, motion detectors, CCTV, security and access control, lifts and so on. Building Energy Management Systems relate specifically to energy-related systems.
Small buildings may have independent controls for energy systems, but for larger or more complex buildings, sites with a number of buildings, or organisations with buildings on a number of sites, the integration of systems operation through a single Building Energy Management System offers greater control and can achieve significant savings. NB Increasingly, simple BEMS are being developed that are suitable for even the smallest buildings.
BEMS provide real-time remote monitoring and integrated control of a wide range of connected systems, allowing modes of operation, energy use, environmental conditions and so on to be monitored and allowing hours of operation, set points and so on to be adjusted to optimise performance and comfort. BEMS can also trigger alarms, in some cases predicting problems and informing maintenance programmes. They allow records to be kept of historical performance, enable benchmarking of performance against other buildings or sites and may help automate report writing.
In 2014, BSRIA reported that the global BEMS market was worth $3.5 billion, or 3 billion Euros, and was growing globally at more than 10% per annum. This increasing interest has resulted from the rising cost of fuel, concerns over energy security, increasingly aggressive environmental targets and the reduced cost of sensors, analytics software and data storage.
Claims for the scale of savings that can be achieved by BEMS range from 10% to 25%. Operated properly, they should allow energy use to be optimised without compromising comfort or performance. However this requires a thorough understanding of how buildings are supposed to perform, and how different systems within them interact.
To function correctly they must be properly designed, installed and commissioned and must have a user interface that is easy to operate. They should then be continually assessed and fine-tuned as performance is better understood over a number of seasons and modes of operation, and changes are made to buildings or operations. Maintenance is also necessary to ensure systems continue to operate correctly, for example, replacing sensors and batteries, checking connections, checking the operation of dampers and valves, upgrading software and so on.
BEMS can be independent installations with separate maintenance contracts, or manufacturer installations which include maintenance. They can be wired or wireless systems. To determine whether a wired or wireless system is the most appropriate, buildings should be audited to test how well signals can be received and how likely disturbances are. Choosing the correct BEMS system then depends on the size and usage of the building, the scale of the project and the budget. As a general rule, larger, more extensive projects tend to be best suited to wireless solutions.
BEMS may have remote outstations that can be interrogated locally, or may be accessible from mobile devices. However, major buildings may be vulnerable to cyber attack, especially when they are associated with prominent organisations. This can be a particular issue where functions operate in the 'cloud', such as cloud-based analytics, and the ability to access and manage multiple buildings remotely. The ability to access live analytics, or receive alarm notifications from hand-held devices has great potential benefits, but may also bring additional risks.
[edit] Related articles on Designing Buildings
- Air conditioning.
- Automated blinds.
- BACS building automation controls - the information revolution.
- BS EN 15232 Energy performance of buildings: impact of building automation, controls and building management.
- Building Automation and Control System BACS.
- Building energy efficiency - is building automation the answer?
- Building energy management systems (BEMS) for data centres.
- Building energy simulation software.
- Building management systems
- Building services.
- Building services engineer.
- Commercial building automation market.
- Cyber threats to building automation and control systems.
- Data centres.
- Energy management and building controls.
- Energy management in the built environment: A review of best practice.
- Global BACS market resilience.
- Global building energy management systems market.
- HVAC.
- Internet of things.
- Mechanical, electrical and plumbing MEP.
- Smart buildings.
- Smart meter.
- Smart technology.
- US Smart Connected HVAC in Commercial Buildings Study 2017.
- Wireless vs wired building energy management system.
Featured articles and news
The UK's Modern Industrial Strategy: A 10 year plan
Previous consultation criticism, current key elements and general support with some persisting reservations.
Building Safety Regulator reforms
New roles, new staff and a new fast track service pave the way for a single construction regulator.
Architectural Technologist CPDs and Communications
CIAT CPD… and how you can do it!
Cooling centres and cool spaces
Managing extreme heat in cities by directing the public to places for heat stress relief and water sources.
Winter gardens: A brief history and warm variations
Extending the season with glass in different forms and terms.
Restoring Great Yarmouth's Winter Gardens
Transforming one of the least sustainable constructions imaginable.
Construction Skills Mission Board launch sector drive
Newly formed government and industry collaboration set strategy for recruiting an additional 100,000 construction workers a year.
New Architects Code comes into effect in September 2025
ARB Architects Code of Conduct and Practice available with ongoing consultation regarding guidance.
Welsh Skills Body (Medr) launches ambitious plan
The new skills body brings together funding and regulation of tertiary education and research for the devolved nation.
Paul Gandy FCIOB announced as next CIOB President
Former Tilbury Douglas CEO takes helm.
UK Infrastructure: A 10 Year Strategy. In brief with reactions
With the National Infrastructure and Service Transformation Authority (NISTA).
Ebenezer Howard: inventor of the garden city. Book review.
The Grenfell Tower fire, eight years on
A time to pause and reflect as Dubai tower block fire reported just before anniversary.
Airtightness Topic Guide BSRIA TG 27/2025
Explaining the basics of airtightness, what it is, why it's important, when it's required and how it's carried out.
Construction contract awards hit lowest point of 2025
Plummeting for second consecutive month, intensifying concerns for housing and infrastructure goals.
Understanding Mental Health in the Built Environment 2025
Examining the state of mental health in construction, shedding light on levels of stress, anxiety and depression.
The benefits of engaging with insulation manufacturers
When considering ground floor constructions.
Lighting Industry endorses Blueprint for Electrification
The Lighting Industry Association fully supports the ECA Blueprint as a timely, urgent call to action.