The high efficiency ECHO IT Cooling System takes advantage of all the available energy saving opportunities currently available in data centre cooling technology. When compared to a modern conventional downflow chilled water system, the ECHO achieves energy reductions in the region of 56%, with payback of the increased capital costs of the system retrieved in less than a year.
The ECHO system meets the cooling parameters of latest IT hardware, not only in terms of temperature but also airflow and pressure. This ensures the right air temperature, in the correct quantity and at the correct pressure is presented to the server inlet, enabling it to breathe efficiently. By varying the air volume, the ECHO system operates not only with air volumes 50% less than traditional cooling systems but much more efficiently and with elevated water temperatures that allow up to 95% free-cooling.
At the hub of the ECHO system is an ACE (Active Cabinet Exhaust) unit which sits on top of the server cabinet, drawing precisely the right amount of hot discharge air from the servers and rejecting it away into the ceiling void, without any impingement into the IT
environment. The air is ducted directly to an Airedale ECHO CRAC unit which in turn is linked to one or more Airedale ECHO free-cooling chillers via interactive controls logic and intelligent software. This smart, controls logic, matched with all the latest technology
direct drive EC fans and chilled water coil technology, is key to the ECHO’s ability to communicate from rack to chiller and gives the ECHO system its intelligence, high efficiency and resilience.
The ACE combined with the Airedale ECHO CRAC unit creates a temperature neutral environment that intelligently measures and provides the air volumes demanded by each individual rack. Because the hot discharge air from the servers is managed, there is no re-circulation into the IT space eliminating the need for any hot aisles. This allows the
optimum utilisation of data hall floor space. Since the Airedale ECHO CRAC unit provides the primary heat transfer of the cooling system, the ACE is completely dry, involving movement of air only. Moreover all noise is contained. The ACE unit is contoured to allow data cabling to the rear of the cabinet and allows access to the rack without impairment. The Echo system ensures that the entire data centre, front and rear of rack, is at server inlet temperature creating a more comfortable working environment for IT operatives.
With the higher operating temperatures of the ECHO system, concurrent free-cooling and mechanical cooling can be achieved for 95% of the year and full free-cooling for over 50% of the year. The graph shows the ambient profile for London, where the ECHO system enables free-cooling even with ambient temperatures up to 21°C. Free-cooling is achieved indirectly, which means there is no introduction of air from outside which would require a higher degree of filtration, humidification and a full mechanical cooling installation for times of peak load. This keeps operating costs to a minimum and reduces indirect carbon impact.
By measuring pressure in the server rack, the ECHO system controls the ACE fans to ensure they mirror the fans cooling the servers inside the cabinet. The ACE is sympathetic to IT hardware and is fitted with the exclusive Cabinet Differential Pressure Control (CDPC) system maintaining pressure in the rack within the server design envelope, whilst still ensuring temperature is controlled.
Monitoring points of the control system maintain a positive pressure within the floor void and at the front of server, while creating a negative pressure at the rear of the IT cabinet and return air void to ensure no discharge air short circuits to the server inlet. Slight differential pressure across the IT hardware is precisely controlled so that air is not ‘forced’ through the IT equipment.
By installing the ECHO system, it is possible to future proof the data centre such that it can operate at low, medium and high densities. The system allows a uniform heat load density per cabinet that can be altered over the life cycle of the data centre, so there is no need to stipulate high density cabinet positions from day one.