The majority of large European businesses plan to expand their data centre facilities in the coming year, according to a survey backed by Digital Realty.

The survey polled 200 senior IT decision makers at European businesses with over £500 million in revenue. It found that 85% plan to expand their data centre facilities, up slightly from 2011.

However, only 23% of respondents said that expansion would "definitely" take place – fewer than last year – with 62% reporting that it will "probably" happen.

There was growing interest among respondents in building their own data centre facilities, with 42% preferring that option this year, up from 30% in 2011. Fewer organisations expressed interest in leasing data centre space from a dedicated provider (32%) but that proportion grew at a faster rate, doubling from 18% last year.

More respondents were aware of the power usage effectiveness (PUE) of their data  centre facilities this year, up from 82% in 2011 to 88%. Digital Realty took this as a sign that "organisations are making greater efforts to improve the efficiency of their existing data centres", although it could simply reflect the growing prevalence of PUE as a metric.

The average reported PUE among respondents was 2.61, meaning that 38% of the electricity put into the data centre ends up powering IT workloads.This is down (i.e. an improvement) from 2.66 last year.