Recommendations of air-conditioning inspection reduce carbon emissions from Eland House
Implementing the recommendations of an air-conditioning inspection carried out by Efficient Air last year has improved the energy performance of the Eland House headquarters of the CLG by 12.6%. The energy saving is 662 MWh a year, valued at £41 000. CO2 emissions are calculated to have been reduced by 250 t.
The air-conditioning inspection was the third stage in assessing the performance of this 11-storey building in London. Eland House has a C rating for its Energy Performance Certificate but only an F for its DEC for operational efficiency.
Efficient Air worked with consulting engineers Faber Maunsell and the resident facilities-management team, MITIE Engineering, during the inspection. Its aim was to identify zero- and low-cost initiatives and opportunities for capital investment.
Implementing the 10-point action plan prepared by Efficient Air would improve the building’s operational efficiency to an E rating.
Carl von Reibnitz, sustainability manager at CLG, says, ‘The “Article 9” air-conditioning inspection has proved to be a great success, with the initial costs being recouped very quickly. It not only backed up our own analysis, but provided us with further low/no-cost quick wins and capital-investment opportunities.’
The 10-point action plan is listed below.
• Standardise on temperature set-points to eliminate fighting between units and chilled beams.
• Ensure a dead band of at least 3 K (±1.5 K) is factored into BMS strategies to prevent simultaneous heating and cooling between air-handling units, perimeter heating and chilled beams.
• More frequent calibration of temperature and pressure sensors for optimum control efficiency.
• Replace faulty cooling and heating valves, letting by when closed.
• Reduce the over-supply of airflow on AHU 4.
• Set control damper actuators for free cooling and heat reclaim optimisation from re-circulated air.
• Increase frequency of filter changes.
• Replace old-technology fans with new high-efficiency technologies.
• Change the control of the ‘on floor’ chilled-water pump to reduce use of chilled beams during winter.
• Repair and improve lagging on ductwork and pipe-work to minimise losses.