A 10-storey upgrade of fan coil units has seen a London services firm claim energy savings of the order of 75 per cent. RAC reports
A collaboration between fan giant ebm-papst, FM firm Norland Managed Services and energy specialist Cinque Energy Solutions has reaped huge savings upgrading the fancoils on the London commercial office building.
The upgrade on the HQ of an unnamed multinational professional services firm, involved replacing AC fan motors nearing the end of life with high efficiency EC fans with a customised control platform.
The entire upgrade involved 1,200 fan coil units (FCUs) across the 10-floor building.
The aims of the upgrade were: to reduce the energy consumption of the HVAC equipment; to reduce noise; to reduce maintenance; and to increase the controllability of the HVAC system in the building.
As part of the upgrade, a customised control platform was incorporated, allowing the HVAC system to be controlled effectively on-site. The control platform also enabled the performance of the system to be properly monitored following the upgrade.
The full upgrade is predicted to provide total energy savings of 75 per cent.The client initially requested Norland Managed Services to recommend a range of energy saving opportunities within its headquarters building in London.
Based on the selected project identified by the client, the consortium of ebm-papst, Norland Managed Services and Cinque Energy Solutions estimated that the upgrade of 1,200 FCUs would provide energy savings of the order of 60 to 70 per cent.
The project consisted of manufacture, supply and installation of new EC fan decks and new controls, replacing AC fan decks with EC fan decks with variable speed control between 0 and 10v.
Based on the upgrade proposal, the collective team conducted a trial to highlight the potential of the energy saving opportunities. One fan coil unit of each size was manufactured and then installed in the building.
The power draw was measured on the original units before and after the new EC deck was installed. These measurements showed a huge difference in power consumption.
For the larger unit, the AC fan deck drew 247 W, compared with just 49 W for the EC fan deck, while for the smaller unit, the AC fan deck drew 150 W, compared with 54 W for the EC fan deck.
Following the trial, the consortium made a series of modifications, including increasing the number of fans in the large unit, which allowed the fans to be run at a slower speed, leading to a further reduction in kW and a further reduction in noise.
Additional controls and monitoring were also requested to allow remote speed setting and feedback.
After the trial, the upgrade of all fan coil units on the first floor commenced, comprising installation of the EC fan decks and a new control system for the fan coils.
This was then rolled-out across the entire building - 1,200 fan coil units in total across the ten floors, together with new controls.
When deciding what controls would be selected, the teams had to take into account the requirements from the client for a customised control system, including remote fan speed control and alarm monitoring.
The team also needed to ensure that these installations were achieved without office disruption.
The agreed controls solution included a thermal management system (TMS) controller for control and monitoring of up to four fans; a zone controller for control and monitoring of a network of FCUs; and a master controller for all of the FCUs within the building.
Each set of controls interfaced with the other to allow the entire set of FCUs within the building to be controlled and monitored.
The completed project is predicted to achieve nearly £54,000 in savings each year, along with improved controllability and monitoring for the occupant. Other benefits included perceptibly lower noise and an extended life for the system.