Introduction

Building controls, whether stand-alone units or full building energy management systems (BEMS), are designed to provide a comfortable climate for building occupants while ensuring this is delivered with the lowest possible energy consumption.

Controls can be used to manage heating systems, cooling systems, air conditioning systems, lighting systems and blinds, as well as fire and security systems and lifts. They can also be used to directly collect and display data from meters. Energy data can then be displayed on the BEMS; having good quality data about actual energy consumption is the key to achieving an energy efficient building.

Demand-based control is the most energy efficient approach; turning systems off when not needed or, if this cannot be done, then at least turning them down.

Energy can account for about 40% of the running costs of a building over its lifetime (Figure 1). Anything that can be done to help manage this effectively is a benefit to building owners and occupants. Any decision on what to specify should be based on lifecycle costs, not short term thinking about the initial capital cost.

Controls can be applied equally successfully to a new or refurbished building. A growing trend is greater integration. The best way to achieve this is to use products which utilise open communication protocols such as BACnet, KNX, LON, Modbus and M-Bus.

Remote access is also now possible, allowing a Facilities Manager (FM) or a Service Engineer to interrogate the system remotely and diagnose problems. It may even allow for the plant to be switched on or off for special events without the need to be on-site.