How Does EcoCooling Work?

Celsius and EcoCooling have been working with data centres and server room equipment manufacturers to develop a modular system of cooling for retrofitting to existing facilities to provide energy efficient cooling. Comprehensive process controls maintain compliant temperatures together with all of the connectivity required for the secure and safe operation of the total package.




Computer Room Air Conditioners (CRACs) use a refrigeration system to cool air and pass it to the void under the raised floor.



An EcoCooling unit takes external air and passes it to the void under the raised floor. Below 18°C ambient air is taken and mixed with air re-circulated from the hot aisle. Above 21°C the EcoCooler uses evaporative cooling to provide air which never exceeds 22°C.


For the vast majority of the year the air in the UK is significantly below the ideal temperature of a Data Centre, there is a lot of 'free cooling' out there, so why don't we use it? Having studied the cumulative count of hours over 5 years (including 2003 with the record hot days) for UK weather conditions we see that it was only above 21C for 2448 hours which represents 4.9% of the time, so for 95.1% of the time it is below 21Co. We also see that the Wet Bulb Temperature of the air never went over 23C. 


An EcoCooling free air system provides a constant flow of low carbon cooling, attemperated air between 18°C and 22°C. No refrigeration is used 'the air is cooled by evaporative cooling when ambient temperatures are high and is heated by recirculation of air from the server exhaust when the ambient temperature is low. No refrigeration is used as all of the cooling is achieved using evaporative cooling. This results in energy saving in excess of 90% compared with traditional Computer Room Air Conditioners (CRAC's)

Modern IT equipment is robust and has a typical environmental operating range of 10C to 35C and a humidity range from 20% to non-condensing. Close control refrigeration equipment is not necessary to maintain these conditions, low carbon cooling can be used if controlled correctly.

It really is legacy thinking to keep Data Centres at 20Co when it is costing a fortune to maintain such low temperatures, even ASHRAE have recently moved their specification to reflect this increased reliability of the modern equipment in Data Centres, by increasing the temperature required to between to 18Co '27Co for Data Centre Cooling.

ECPCREC – The EcoCooling Computer Room Evaporative Cooler is designed to meet the Data Centre cooling needs of modern IT equipment. This is a modular system based on the standard ECP EcoCooler incorporating a patented 'attemperation' system.
Energy Efficient 'Attemperation' Using the warm air in the Data Centre to temper the cold incoming air in the winter.

Importantly, this 'attemperation' section allows the cooler to maintain perfect Data Centre conditions year round 'perfect whether it's a sweltering 35Co outside or a freezing cold -15Co the data centre will still be ASHRAE temperature compliant.

1 Fresh air is brought into the system though primary filtration and wetted filter pads
2 EcoCooling Evaporative cooling operates during warm periods
3 Low carbon cooling is achieved by a Low energy axial fan air distribution
4 Patented control system controls air supply temperature
5 Air flow is matched to density of cooling required
6 Hot and cold aisle arrangement of racks is preferred
7 Room is kept at a positive pressure
8 Ceiling void can be used for exhaust path
9 No exhaust fans are used to reduce complexity and energy use
10 Hot air is exhausted to atmosphere


 The air flow required for the system is dependent upon the total IT load and the server design. Using a typical IT of 10C a single EcoCooling CREC can support a load of 35kW for Data Centre Cooling. The systems can be either fixed or variable flow.

The low energy air distribution system uses axial fans which can accommodate most applications. Where raised floors are used, the overall design, in particular the floor grill numbers and position, should reflect the pressure drops and rack cooling load density to achieve true low carbon cooling.

Most EcoCooling systems are controlled centrally. This allows fully automatic control and identification of any fault conditions.


The following must be taken into account when providing an EcoCooling solution:

Temperature: In Europe an EcoCooling system can provide 100% Temperature compliance against the latest ASHRAE[1] standards and meet all manufacturer environmental specifications. Some early main frame systems require close control and evaporative cooling is not suitable.

Relative Humidity: In Europe an EcoCooling system can provide 99% compliance against ASRAE allowable conditions. Older equipment such as paper tape and magnetic tape systems are less tolerant and evaporative cooling is not suitable, in these increasing rare occurrences we can offer standard CRAC cooling, we will always offer the best solution for the application in looking for low carbon cooling.

Dust: The filter pads provide an adequate level of filtration for modern IT equipment with sealed bearings and closed drives, but additional higher efficiency EcoCooling wrap round filters can be provided if required.

Redundancy: 'The required redundancy is met using the EcoCooling modular system.

The key benefits of using EcoCooling compared with conventional refrigeration based air conditioning are:


-          Over 90% reduction in electricity usage
-          Lower capital costs
-          Lower maintenance costs
-          EcoCooling systems qualify for Interest free loans from the Salix schemes, as they are low carbon cooling.


-          Low energy ventilation system
-          Low cost spare parts holding
-          No F gas compliance costs
-          Simple technology
-          Ability to cope with very hot days, the hotter the day the more efficient the EcoCooling unit.
-          Allows release of available power for other activities


-          External access for maintenance.
-          No internal space used
-          EcoCooling Modular system achieves required redundancy
-          Simple expansion through modular design

Environmental Benefits

-          No refrigerants
-          Less than 10% of the carbon footprint of conventional air conditioning
-          Can fit into Carbon Reduction Commitment energy reduction scheme for low carbon cooling.
[1] – 2008 ASHRAE Environmental Guidelines for Datacom Equipment
Contact us on 01926 887470 today for a no obligation quote.