Savvy lighting and heating control saves £355k a year in RBS’s flagship office



RBS set out to maximise the effectiveness of the existing Building Management System that was in place at their flagship office in London, to help achieve its 15% energy reduction target. The main aim of the project was to focus on doing more with the building infrastructure and systems already in place, meaning that the cost of the simple and innovative energy saving solutions were recouped in less than two months.

With over 2,500 properties across the UK ranging from offices to small high street retail units, reducing energy costs is an area of significant focus for RBS. 280 Bishopsgate in the heart of the City of London houses 2,700 employees over 12 floors and is leased by RBS. It’s representative of the multi-occupancy properties that together account for 60% of the company’s energy spend.

Challenges & Actions

An out-of-hours survey of the building gave some key insights which were fed into the computerised Building Management System (BMS). The team then identified a number of actions that would refine the building’s heating, ventilation, air conditioning (HVAC) and lighting controls to ensure that the systems operated in line with when the building is occupied, therefore saving valuable energy. Another simple yet effective step was to make sure that this specialised system controlled all the main HVAC equipment, in turn reducing the opportunity for manual error.

Other measures adopted included:

  • Using fresh air to cool the building rather than using air conditioning
  • Changing the office temperature based on occupant feedback instead of outside temperature hold-offs
  • Identifying and repairing any defective HVAC equipment
  • Consolidating the control system to ensure that boilers and chillers aren’t operating concurrently
  • Re-commissioning the building’s lighting control system

Lessons & Results

We already had the Building Management System in place so it was a case of coming up with a control strategy and re-commissioning. We’re making maximum use of what is in front of us, which is why it’s so attractive and it’s providing significant savings that will sustain going forward.

Total annual cost savings expected from introducing these measures into our top 40 energy consuming offices would see a saving of £4.1m.

In the 280 Bishopsgate office the direct savings are:

  • Electricity – savings of £340k per year & 3.2GWh per year (26% reduction)
  • Natural Gas – savings of £15k per year & 0.4GWh per year (35% reduction)