The last time I heard directly from the Swedish industrial giant Alfa Laval, I was looking at biotechnology, but that was back in the 20th century. The company dates back another century, to 1883, and has an impressively wide portfolio, making equipment for heavy industry, including ships’ engine rooms. It’s done a heck of a lot of pumping, heating, cooling and transporting of stuff, and now it is applying some of that expertise to data centers.
In fact, for its data center products, Alfa Laval seems to have partnered with a specialist, Netherlands based Low Speed Ventilation, and adopted an approach that is different from the mainstream in the industry. While most systems pump air quickly, Alfa Laval is pushing this concept of low speed ventilation (LSV).
Alfa Laval cooling array
Source: Alfa Laval
No hotspots, please
Moving air fast can create eddies, fluctuations and hotspots, says Alfa Laval. The Venturi effect means that pressure actually reduces when air faster through any choke-point, and that will remove less heat.
LSV takes the air speed down from a typical eight or nine meters per second, to around 1.5 meters per second. This means the fans have to operate at lower pressure, at tens of Pascals, instead of up to 1000 Pa. This means they use less power and the overall power usage effectiveness (PUE) can go down as low as 1.07.
There are other spin-off benefits, apparently. The fans vibrate less, so there is less danger of damage to other components in the data centers, and the fans themselves last longer. The overall investment is also apparently lower.
Obviously there are trade-offs to be made. Low speed ventilation has to be reliably produced, and the system requires larger volumes of air. This means it needs more fans, and therefore larger coolers.
But the technique can be applied as an upgrade to existing systems, and works with hot or cold aisle layouts, according to Alfa Laval.
The LSV site says that Low Speed Ventilation is a part of the Dutch company Boersema Installation Advisors, and under this flag it seems to have been getting started in the Netherlands for a few years. LSV is mentioned in a Dutch Energy Ministry white paper of 2012, along with some other Dutch data center technologies.
It really does sound a lot like telling data centers to calm down and breathe more gently, which certainly has some appeal. It presumably works well with the trend to allow server temperatures to increase, which has been gaining ground recently as groups like ASHRAE revise their guidelines, and users accept this can be done without increasing failure rates of the IT equipment too much.
I will be interested to hear more about it and, if it delivers what Alfa Laval says it does, I’m sure we will hear more in due course.