© Empa

Using waste heat from data cen­ters — heat­ing while computing

A new­ly installed data cen­ter in the NEST research build­ing is not only used for data pro­cess­ing, but also helps to heat the entire build­ing. The serv­er facil­i­ty is part of the EU research project “ECO-Qube”, which is inves­ti­gat­ing the inte­gra­tion of data cen­ters into build­ing sys­tems and their ener­gy-effi­cient operation.

A click on the Inter­net leaves traces. Not only in the net­work itself, but also in the form of a large eco­log­i­cal foot­print. Because even though all our data sup­pos­ed­ly floats in the cloud, phys­i­cal data cen­ters are need­ed to process and store it, and these con­sume huge amounts of ener­gy — a sig­nif­i­cant por­tion of which is used to cool the facil­i­ties. The big tech giants are now well aware of their respon­si­bil­i­ties, invest­ing gen­er­ous­ly in renew­able ener­gy and look­ing for ways to opti­mize the ener­gy effi­cien­cy of their serv­er farms. One of these paths leads to the Arc­tic Cir­cle, for exam­ple, where some of the largest data cen­ters are now locat­ed. The cold tem­per­a­tures there help reduce the amount of ener­gy need­ed to cool the equipment.

How­ev­er, with the lat­est dig­i­tal trends such as arti­fi­cial intel­li­gence (AI), “aug­ment­ed real­i­ty” or “Inter­net of Things” (IoT) come the next chal­lenges: The vol­umes of data to be processed are increas­ing immea­sur­ably, and at the same time, reac­tions are required in real time — with­out laten­cy. To achieve this, the pro­cess­ing loca­tion of the data must once again move much clos­er to the point of ori­gin of the same. For exam­ple, in the form of a micro data cen­ter in the neigh­bor­hood. In the best case, how­ev­er, this local data cen­ter is not only used for data pro­cess­ing, but — con­nect­ed to the ener­gy sup­ply — is also used to heat the build­ings. A field test with micro-com­put­ing cen­ters in the NEST research build­ing at Empa and at two oth­er sites in Turkey and the Nether­lands aims to explore the poten­tial of this idea.

Intel­li­gent cooling

The project, called “ECO-Qube,” is sup­port­ed by the EU’s Hori­zon 2020 fund­ing pro­gram and brings togeth­er research and indus­try part­ners from Switzer­land, Turkey, Spain, Ger­many, the Nether­lands and Swe­den. “Our goal is to reduce both the ener­gy demand and CO2 emis­sions of small data cen­ters by one-fifth each,” says Çağatay Yıl­maz, Inno­va­tion Man­ag­er at Turk­ish IT solu­tions provider Lande and project man­ag­er of “ECO-Qube.” Accord­ing to the Sus­tain­able Dig­i­tal Infra­struc­ture Alliance, anoth­er project part­ner, con­ven­tion­al data cen­ters often only oper­ate at a uti­liza­tion rate of around 15 per­cent. Nev­er­the­less, the servers con­stant­ly need pow­er and are cooled. To counter this prob­lem, the cool­ing of the “ECO-Qube” data cen­ters is made intel­li­gent: The sen­sor data of the indi­vid­ual IT com­po­nents are accu­mu­lat­ed in Big Data struc­tures and help to ensure that the heat dis­tri­b­u­tion with­in the facil­i­ty is accu­rate­ly record­ed at all times. Arti­fi­cial intel­li­gence com­bines this data with air­flow sim­u­la­tions so that cool­ing can be high­ly tar­get­ed. At the same time, the com­put­ing loads in the three test data cen­ters in Switzer­land, Turkey and the Nether­lands are dis­trib­uted in such a way that all three facil­i­ties can be oper­at­ed as ener­gy-effi­cient­ly as possible.

Use waste heat

The three data cen­ters will be inte­grat­ed direct­ly into the ener­gy sys­tems of the sur­round­ing neigh­bor­hoods and will be pow­ered by renew­able ener­gy when­ev­er pos­si­ble. In NEST, for exam­ple, the pow­er for oper­at­ing the data cen­ter comes from the pho­to­volta­ic sys­tems of the NEST units and the mobil­i­ty demon­stra­tor move, among oth­ers. The waste heat from the data cen­ter is dis­charged to the exist­ing medi­um- or low-tem­per­a­ture net­work. In win­ter, it thus direct­ly feeds the build­ing’s heat­ing sys­tem and, through­out the year, simul­ta­ne­ous­ly serves as a source for a heat pump that pro­vides domes­tic hot water.

“For us, it is inter­est­ing to look at the micro data cen­ter not just as an elec­tri­cal con­sumer, but as a dynam­ic com­po­nent in the over­all sys­tem that we can use so that cal­cu­la­tions take place when it makes eco­log­i­cal sense. Cou­pling the elec­tri­cal and ther­mal world with the IT infra­struc­ture and data pro­cess­ing offers great opti­miza­tion poten­tial towards sus­tain­able oper­a­tion,” says Philipp Heer, head of the “Ener­gy Hub” (ehub) at Empa.

The project will last about three years. Upon com­ple­tion, the team hopes to be able to pro­vide guide­lines for plan­ners and build­ing oper­a­tors to help them inte­grate data cen­ters into build­ings and neigh­bor­hoods in an ener­gy-effi­cient manner.