GLASGOW-based Smart Metering Systems (SMS) has taken on extra office space in Glasgow after a big increase in its workforce over the past year as it recorded its fastest rate of expansion in the firm's history.

SMS revealed that pre-tax profit was up 42.9% at £7.5 million for 2013, from £5.2m last year. Revenue was up 33% at £27.9m.

The group, which last week announced a new £105m credit facility with Barclays, Clydesdale Bank and Bank of Scotland, saw accelerating growth during the year and its executives belief there is still a large market opportunity to seek.

Chief executive Alan Foy said: "It has been our biggest year of growth so far."

He said that the company had opened another office on Glasgow's St Vincent Street as it hired a another 40 members of staff.

The company now employs around 120 people.

Mr Foy said that the company continued to invest large amounts in staff training to ensure that the data it provided to clients was "absolutely accurate".

SMS's total meter portfolio increased by 38% to 469,000 over the year.

Having added 60,000 to its meter portfolio in the first half, growth accelerated in the latter part of 2013, with another 69,000 added.

The company's focus is on the industrial and commercial sector and it secured contracts with major clients, including Dong Energy, during the year, leading to growth of 118% in its portfolio of business meters last year.

"The current estimates are for a total programme in excess of 22,000 meters by the end of 2014, of which more than 2000 had already been delivered by December 31," the company said.

Its gas supplier client base grew from 13 to 17, who between them represented 80% of the UK business market.

Mr Foy estimates there is a market of 250,000 to 300,000 meters in the industrial and commercial sector to aim for.

"There is a big market in front of us," he said.

He said he was pleased with the company's progress since listing on the stock market three years ago, during which time it has issued profit upgrades three times.

Mr Foy said: "Our progress in 2013 continued to be in line with our strategic priorities, at both a financial and operational level.

"Our gas meter portfolio increased by 38% year-on-year and we signed major new contracts with gas suppliers. We now have contracts in place with 80% of the I&C (industrial and commercial) meter market."

The company has now installed more than 16,000 of its ADM smart metering devices, which allow remote meter readings every half an hour.

SMS's chairman, the former John Menzies finance director Paul Dollman said: "Since SMS floated on AIM in 2011, the company has continued to demonstrate year-on-year growth and has an established and growing market position in the UK smart metering market.

"The business strategy in the medium term is to maintain high levels of service to customers in the gas supplier market, increase the run rate with these customers, and continue to grow the meter asset portfolio.

"SMS has consolidated this position and invested heavily over the years in IT infrastructure to provide a strong foundation for growth with the gas suppliers in the market."

SMS's shares closed down 13.5p or 4% at 328p.