Gemma Reeves , Business Unit Manager specialising in Data Centers for EMEA at Alfa Laval UK , discusses the need for more efficient heat transfer within data centre cooling systems , and how heat exchangers can act as an enabler of green IT .
ccording to data centre specialists , it has been said
A that the world ’ s 9 million data centres ’ CO 2 emissions were equal to that of global air travel in 2019 , and this only continues to rise . The last two years have seen a significant drop in air travel due to COVID-19 but the global lockdowns have prompted an explosion of video conferencing and remote working , leading to some referring to digital infrastructure as ‘ the fourth utility ’.
What many people don ’ t know is that at present , 40 % of an average data centre ’ s energy usage is used solely for cooling . Developing more efficient heat transfer systems and looking at not just the cooling , but the reclamation of the waste heat will be paramount to achieving net zero targets by 2050 . There is a desire in the industry to become greener , however , many data centres are currently far too reliant on mechanical cooling techniques which are simply not a sustainable option for the future . Cue the heat exchanger .
The role of the heat exchanger
There are many possible applications for heat exchangers in a data centre . At the heart of the data centre is the server room , a pristine white space processing millions of megabytes of data every hour . Such sensitive electronic pieces of equipment need protecting at all costs from the dirty exteriors that surround them , and heat exchangers fulfil that exact role as a protective shield , while enabling accurate control of temperature .
There are many common applications for a heat exchanger include a cooling tower interchanger , providing free cooling utilising localised water sources such as the sea or a river , a free cooling interface with dry or adiabatic air coolers , or some of the newer applications in the industry drive to a greener future including liquid immersion cooling and waste heat recovery . We will go on to discuss some of these in more detail .
Heat exchangers come in many forms such as gasketed and copper brazed , and are ideally suited to data centres and their demanding performance targets to achieve reductions in power and water usage . It is crucial to specify the right heat exchanger for the job , involving the heat exchanger manufacturer early in the design process will ensure a design that delivers the right performance over the whole life cycle .
An invaluable indicator of a heat exchanger ’ s performance is whether it is certified by the industry-trusted Air-Conditioning , Heating and Refrigeration Institute ( AHRI ). This independent organisation develops standards and certification programmes to ensure that the unit supplied will perform as specified .
Reducing reliance on mechanical cooling
While mechanical cooling has certainly served a purpose over the years , it is fundamentally based on using energy to cool a system , often using fossil fuels or electricity to achieve this . These days , it is
Improving heat transfer efficiency in data centres
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