One of the six big pledges in the Conservative Party’s 2019 manifesto was to reach Net Zero carbon dioxide emissions by 2050. However, the nation’s building stock is responsible for nearly a fifth of domestic greenhouse gas emissions – so it stands to reason that building owners and managers are likely to face growing pressure to save energy.

Looking specifically at power distribution, Smart Buildings Magazine asked Sean Massey, product marketing manager at ABB, to explain how the latest breed of moulded case circuit breakers (MCCBs) can help.

How are priorities changing for power distribution systems?

MCCBs are widely used to control the flow of power in commercial and industrial buildings. They work reliably, are affordable and provide a straightforward service.

However, today’s operators want to save energy, deploy remote monitoring and condition-based maintenance. This will help to control budgets and future-proof themselves against coming legislation.

We’re also seeing operators want functions such as accurate sub-metering of feeds to tenants; remote control and communication capabilities for participation in Demand Side Response (DSR) schemes; or avoiding penalty tariffs such as the ones introduced by Ofgem under the DCP161 legislation in 2018.

These functions require three capabilities: accurate metering, digital communication and in-built intelligence in the circuit breakers that are central to power distribution.

How can the latest MCCBs help?

The latest generation of MCCB provides more performance in a smaller package than previous units. For example, ABB’s Tmax XT can provide up to 1600 A breaking capacity in a smaller size than older models. This can help operators to squeeze more functionality into their existing electrical cabinets.

New MCCBs are available as a straightforward circuit breaker for sites that don’t need smart functionality. However, they can also be supplied with accurate metering of current, voltage, frequency, power and energy. In addition, they can integrate with SCADA or building management systems as they offer compatibility with multiple communication protocols such as Modbus RTU and Modbus TCP, Profibus, Profinet, DeviceNet and IEC 61850.

Lastly, MCCBs can be equipped with software to enable them to provide the sophisticated level of protection needed to operator motors and generators, to act as the controller for a grid edge facility or to provide protection for a grid connection for solar panels or wind turbines.

How can MCCBs help to minimise energy consumption?

A power management function has huge potential to help building owners manage their energy more efficiently. When Ofgem introduced the DCP161 legislation, it enabled utilities to charge penalty tariffs of up to three times the standard energy price when a customer draws more power than agreed. As a result, building owners are keen to ensure their Half Hourly (HH) consumption never exceeds the maximum agreed value.

Traditionally, power management has been carried out by installing load control devices to manage each load individually, as well as accurate metering, PLCs and switchgear controllers.

The latest generation of MCCBs is capable of providing the same functions with no need for engineering a system of load control devices.

The MCCB will monitor its own metering data to evaluate average HH power demand. An in-built algorithm with then automatically deactivate low priority loads to keep power demand below peak, before reconnecting them when demand has subsided.