Pilot scheme is energy-saving success for Land Securities
Published: 08 September, 2016
How did a 12-month proof-of concept scheme lead to Land Securities achieve its 2020 energy-reduction targets four years earlier than expected? Chris Coath of NG Bailey explains.
Energy savings and sustainability are high on the corporate agenda at the minute. While this is not something that can be achieved overnight, a short-term focus can deliver long-term benefits.
Last year we developed a 12-month ‘proof of concept’ pilot scheme in partnership with Land Securities to reduce energy consumption within six of its highest energy-using properties in London.
Having managed the facilities at a number of key Land Securities properties across London, we were already attuned to one of its key corporate goals — to be the leader in sustainability in the UK-listed real-estate sector.
The pilot scheme was born out of Land Securities’ specific sustainability targets — to reduce energy usage across its property portfolio by 15% by 2020.
Land Securities set us a target of an 8% energy saving. By the end of the 12-month programme, we had achieved a 9% reduction in energy consumption across the sites.
The success of the pilot was based on the two companies working in partnership to collate and analyse key energy, control, asset and environmental building data in order to identify and deliver the energy savings.
While there was no shortage of building data available, the key to achieving success in the short-term was being able to access, analyse and act upon the data, often in real time.
We developed an approach and processes that would ensure all the relevant data could be analysed remotely and acted upon quickly by our on-site teams of maintenance engineers to maximise the energy-saving benefits.
The data analysis enabled us to identify assets within each building that could be optimised and upgraded. These were distilled into energy conservation categories and prioritised.
By using a blend of different services and products, a number of energy-reduction projects could be tailored to the specific needs of each building.
We developed a remote energy centre to manage the data analysis, and our energy experts were able to increase efficiencies by providing detailed reports to the on-site energy teams, which managed the individual systems.
The delivery took four key stages.
• Asset optimisation to maximise energy efficiencies.
• Capital projects to replace or upgrade assets.
• Proactive and reactive maintenance by our on-site teams of engineers.
• Communication with tenants to demonstrate how their behaviours could positively influence energy consumption.
More than 40 separate energy-management projects were identified and completed over 12 months.
For example, during warmer temperatures in the heating season. a boiler glide strategy was applied at each site to reduce gas consumption and make use of the thermal energy stored within the building, saving over 100 000 kWh.
Widening the dead bands of fan-coil units and resolving rogue demand signals in the HVAC systems allowed for more constant temperatures across customer floors and helped to mitigate uncomfortable hot and cold spots. This contributed to a 213 000 kWh saving at one site.
And optimising of the time scheduling of the major HVAC plant at New Street Square helped reduce gas consumption by 97 000 kWh and achieve electricity savings of 70 000 kWh.
At 80-100 Victoria Street, which will be home to Land Securities’ head office from 2017, the chiller plant was optimised, allowing for sequencing with a bias towards energy efficiency and saving over 125 000 kWh of electricity a year.
Analysing energy-consumption data at the same site also led to a project designed to reduce normal out-of-hours energy usage.
Overnight and at weekends, the energy consumption for central plant was high for only one or two occupiers’ requirements. This resulted in high gas usage out of hours and excessive electricity usage associated with pumping and distribution.
The building’s boilers were not operating sequentially in line with demand, and three boilers were running in low-fire mode simultaneously. The building controls strategy was not allowing for boilers to ramp back in low-demand conditions.
As a result of the system changes made, the central boiler and chiller plant were corrected to run sequentially, and ramp back, in line with occupier demand.
We saw immediate savings in energy usage outside of occupied hours, and the optimisation of central plant systems is now being explored across the rest of the commercial portfolio to see if similar savings can be achieved elsewhere.
Overall, the pilot resulted in a 7.2 GWh reduction of energy a year and a saving of more than 2100 t of CO2.
While we achieved this in just one year, this was about investing together in a long-term partnership and developing smarter ways of maintaining Land Securities’ buildings, achieving further energy efficiencies.
This saving contribution led to Land Securities achieving its 2020 energy reduction targets four years earlier than expected, kick-starting its new and ambitious energy and carbon journey.
Chris Coath is head of energy at NG Bailey.
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