The extraordinary amount of energy used by people “mining” bitcoin has been in the news recently, and it’s helped focus attention more generally on the energy we use for computing and data applications, including data centres.
Bitcoin is the cryptocurrency that has been grabbing headlines as it zooms up like a rocket – before falling back again like a damp squib. No doubt it has many more ups and downs to come. People who provide computing power for bitcoin globally are called “bitcoin miners” and the head of Iceland’s power generation company has recently had to explain that these people are now the biggest users of power in his country – using more power than all households combined.
Data centres set to produce as much CO2 as airlines
In fact, commentators have recently been speculating that quite soon, the energy used in cooling IT equipment will exceed the power used in running the systems. That’s before new, power-hungry tech like blade servers are widely introduced. A McKinsey report has apparently stated that by 2020, data centres and IT will produce as much CO2 as the airline industry.
Enormous data centres, critical to Cloud computing, are massive users of energy. Where large amounts of energy are produced, you get a heating effect. Of course, servers don’t like high temperatures, so data centres have to use specialised heating, ventilation and air conditioning (HVAC) to keep the equipment at the correct temperature – potentially using yet more energy.
Where there’s a high energy bill, it’s worthwhile spending some money to lower it. So specialist HVAC surveys and installations are now being commissioned by these centres, in an effort to “green” their power use.
This effort needs to start with the data centre managers, who are often not that knowledgeable about heating and cooling systems, tending to overcool the air being supplied. The trick is actually to get the fans in the servers to work more efficiently – and that’s a matter of airflow management, rather than simple cooling.
Airflow management matters more than cooling
Once airflow is properly managed, temperature is more evenly distributed across the facility and a lower volume of cooled air needs to be supplied. This can reduce air con costs by an estimated 20% – 30%, especially if outside air is used when the temperature permits. Cooled air often escapes between the server cabinets, so another strategy is to ensure that gaps are blocked off and the cooled air has nowhere to go but through the servers.
It’s clear that a combination of better airflow design and management, with an understanding of the actual temperatures required, could contribute to lower energy usage in data centres. The first step has to be to get a company with experience of HVAC in this kind of environment to take a look at where the energy loss is occurring, and then to identify where efficiency could be improved.
Data centres are already being restricted in some areas because of the amount of power they draw – so efficient heating and cooling is going to be high on the agenda as managers look to reduce their energy bills.