Data Centres Case Studies

  • British Airways


    Star Refrigeration’s ammonia thermosyphon cooling system has been granted Millennium Product status by the Design Council, after Prime Minister Tony Blair challenged businesses to show that Britain is the creative powerhouse of the world.

    The thermosyphon cooling system is a highly efficient, water-chilling system designed to provide “free cooling” when weather conditions allow. When the outside temperature is low enough, cooling is achieved without running the chiller’s compressor, which is its major energy consumer, allowing a natural circulation of refrigerant between the evaporator and the condenser to be set up.

    According to Star's Managing Director John Rowell: “In 1997 we developed the thermosyphon cooling system, in association with the building services consultants Justham Dunsdon Partnership, to operate with ammonia as the refrigerant. This system has arguably the highest efficiency and lowest environmental impact of any mechanical refrigeration plant in operation in the world. I am hoping that as a Millennium Product, the ammonia thermosyphon cooling system will be selected for inclusion in the Millennium Dome.”

    The first ammonia system, with a cooling capacity of 3,300kW, was installed for British Airways’ new computer data centre at Heathrow.

    Its power consumption is only 34% of the next most efficient system considered for the project, saving the customer an estimated £166,000 per year in electricity bills. Other thermosyphon cooling projects recently completed include the first single chiller installation for comfort cooling of Natwest’s new telephone call centre in Bradford and a paint cooling application for the Ford Motor Company at their factory in Genk, Belgium. The Natwest Project was the winning entry in the 'As Built Environment' category of the Engineering Council’s 1999 Environmental Award for Engineers.

    Andrew Summers, Chief Executive of the Design Council, said: “We offer our warmest congratulations to Star Refrigeration for the selection of the ammonia thermosyphon cooling system as a Millennium Product. We sincerely hope that it will be a big success for the company and we hope that Millennium Product status will encourage Star Refrigeration in further successful developments.”

    Star Refrigeration is the UK’s largest independent industrial refrigeration engineering company. Star focuses on the design, manufacture, installation, commissioning and maintenance of industrial refrigeration systems. The company offers a turnkey package to all users of refrigeration plant.

    Established in Glasgow in 1970, Star has over 260 employees nationwide and provides fast response 24-hour technical support from a network of nine branches to customers throughout the UK.

    Star’s technical advisory arm, Star Technical Solutions (STS), operates as an independent consultancy providing advice on engineering issues. Star also owns food freezing and chilling equipment specialist Starfrost, as well as mechanical and electrical contractors Penec.


  • Financial Institution Data Centre


    Star Refrigeration has installed a bespoke cooling system at a UK data centre operated by a major financial institution for retail and commercial banking.

    A world leader in cooling and heating system innovation, Star replaced an existing R22 refrigeration plant with a highly energy efficient, low maintenance solution. Star has provided the banking client with a state-of-the-art data centre cooling system designed for low carbon, cost saving operation.

    Operating as a data centre since 1990 in a confidential location, the building features two main data halls, each with independent power and cooling infrastructure. Earlier this year IT and computer server systems in one of the data halls were being replaced as part of a major refurbishment programme.

    Elevated air temperature within the refurbished hall due to the new server equipment demanded a new cooling system with a total capacity of 4,400kW.

    The existing plant had a total cooling capacity of 2,700kW and operated on R22, an ozone-depleting HCFC refrigerant currently being phased out by EU regulations.

    The new cooling system features four 1,100kW chillers operating on the synthetic refrigerant R134a. The innovative design incorporates revolutionary oil-free Turbocor compressors, with variable speed drives and high efficiency at full and part load. The chillers also feature an air-cooled refrigerant circuit configured for thermosyphon operation to provide “free cooling” when possible.

    Star Refrigeration’s Director of Sales – Process, Alan Walkinshaw, says: “Power consumption in data centres has quadrupled by some estimates over the last decade. Operators are increasingly looking to reduce energy usage by IT and associated building support systems such as cooling.”

    He adds: “In this case our banking client wanted a cooling solution with up to date technology, high efficiency and minimal environmental impact. The solution we adopted was an innovative design using revolutionary Turbocor R134a compressors and an air-cooled refrigerant circuit. The system is configured to provide free cooling by automatically switching to thermosyphon operation for much longer periods than the previous system.”

    Additional AHUs (air handling units) to deal with the increased heat load were mounted on the perimeter of the data hall to maintain room air at a supply temperature of 22°C. A new exterior deck was built alongside the existing plant room to accommodate flatbed air-cooled condensers.

    The condenser features variable speed EC fans for low noise operation and maximum efficiency, with epoxy coated fins for longevity. The chillers are fully packaged to minimise potential for refrigerant leakage, with welded steel piping and bellows seal valves.

    When it comes to designing energy efficient cooling and heating systems, Star is a natural innovator. Star works with strategic partners across the globe to deliver low carbon, cost saving solutions.


  • GSK, Brentford


    Star Refrigeration has installed a high efficiency Indigochiller cooling system for specialist air conditioning at GlaxoSmithKline’s global head office.

    GlaxoSmithKline (GSK) is one of the world’s leading research-based pharmaceutical and healthcare companies. GSK House in Brentford, Middlesex, is the company’s prestigious global headquarters.

    Star has designed and installed an environmentally conscious, low carbon footprint chiller solution for GSK House. Star’s compact, packaged Indigochiller is serving a new IT data centre at the Brentford site.

    The data centre operates around the clock with a continuously high base heat load generated by a mass of computer servers. Star’s Indigochiller was chosen following a competitive tender process, which highlighted a significant saving in energy, carbon emissions and lifecycle running costs.

    GSK’s water-cooled Indigochiller has a total capacity of 1,000kW. The system employs water from the local canal to cool the condenser and maximize efficiency. Located externally, the compact packaged chiller delivers cooling to the data centre building via chilled water pipework.

    Star’s Sales Director Rob Lamb says; “As a reliable, high efficiency system, Indigochiller met GSK’s carbon reduction requirements and exceeded expectations with its low life cycle running costs.”

    He adds: “Indigochiller offers the ultimate cooling solution to forward-thinking operators. It is designed for unrivalled performance in process cooling and air conditioning.”

    Star worked in conjunction with the facilities management company for GSK House. The contract was one of a number of cooling projects undertaken by Star for GSK in 2008, including sites at Ware, Barnard Castle and Dungarven.

    Star’s Indigochiller is a low charge, high performance chiller for medium to large scale air conditioning and process cooling operations. Available as an air-cooled or water-cooled unit, Indigochiller has capacity options ranging from 240kW to 1,500kW.

    Indigochiller is highly energy efficient. Star’s research shows that it uses only 60% of the energy required by a standard chiller operating on typical load and ambient profiles. This offers end users a significant saving in energy and running costs.

    Indigochiller is engineered to have minimal effect on the global environment. Developed in direct response to F-Gas regulations, the design aims to eliminate refrigerant leakage. It features bellows seal valves, sealed expansion valves and welded steel pipework.

    Indigochiller features the revolutionary Turbocor centrifugal compressor. It operates on low noise electromagnetic bearings and uses the synthetic refrigerant R134a. The unique oil-free system offers reliable, hassle free performance and requires minimal installation, servicing and maintenance. A robust PLC control system allows the user to monitor running conditions and optimise efficiency.

    Indigochiller is part of Star’s range of environmentally conscious cooling and heating solutions for the building services and process cooling markets. Other products include the low charge ammonia packaged Azanechiller, Freechiller – the ‘free cooling’ solution for IT data centres and Envitherm, providing cooling and heating for hotels, offices and factories.

    Star Refrigeration is the UK’s largest independent industrial refrigeration engineering company. Star focuses on the design, manufacture, installation, commissioning and maintenance of industrial refrigeration systems.


  • Strathclyde University


    Students using the library at the University of Strathclyde in Glasgow are keeping their cool thanks to an air conditioning system from Star Refrigeration.

    The University of Strathclyde was looking to replace an aging refrigeration plant in the Curran Building. The six-storey facility is home to the Andersonian Library, which houses university archives and main collections including books, journals and electronic resources.

    Star had previously supplied an Indigochiller refrigeration plant for cooling in another building on the Glasgow campus. The university was impressed with the build quality and performance of Star’s Indigochiller, which is designed for reliable and highly efficient operation.

    The university’s library had an existing air conditioning plant operating on R22, a refrigerant currently being phased out due to its ozone depletion potential. Engineered to have minimal effect on the global environment, Star’s Indigochiller has a robust design that aims to eliminate refrigerant leakage and offer over 20 years service.

    Star designed, manufactured and installed two Indigochillers on the roof of the Curran Building, each with a 750kW cooling capacity. The chillers cool water from 12°C to 6°C, which is then pumped to air handling units throughout the six-storey building for comfort cooling. The building also houses training facilities for the University of Strathclyde’s National Centre for Prosthetics and Orthotics.

    Andy McWatt from the University of Strathclyde’s Estates Management department says: “In recent years the failure of standard package chillers from other manufacturers had proved both disruptive and expensive for the university. We considered various products featuring the state-of-the-art Turbocor compressor. We found Star’s Indigochiller had the operating efficiency and build quality we were looking for.”

    Star Refrigeration’s Sales and Marketing Director Rob Lamb adds: “Indigochiller stands out from the rest of the market thanks to a range of unique design features and leak-tight components. It is manufactured to ensure maximum efficiency, longterm reliability and low life-cycle costs. These were key considerations for the University of Strathclyde when selecting a chiller.”

    The low charge, high performance Indigochiller features the revolutionary Turbocor compressor, which is low maintenance by design to ensure lifelong trouble-free running. The oil-free compressor operates on electromagnetic bearings and uses the synthetic refrigerant R134a. The system offers reliable performance and requires minimal installation, servicing and maintenance.

    Indigochiller is manufactured from the highest quality components selected to minimise the risk of refrigerant leakage, reduce maintenance costs and enhance operating life. Standard features include ‘leak-free’ bellows seal valves, sealed expansion valves and welded steel pipework. The air-cooled Indigochiller has epoxy coated condenser fins as standard to reduce the risk of corrosion damage.

    With growing demand to cut refrigerant leakage to meet F-Gas regulations, Star developed its Indigochiller for medium to large scale air conditioning and process cooling. Highly energy efficient, it uses only 60% of the energy required by a standard chiller operating on typical load and ambient profiles. This offers end users a significant saving in energy and running costs.

    Available as an air-cooled or water-cooled unit, Indigochiller has capacity options ranging from 250kW to 1,650kW. A robust PLC computerised control system allows the user to monitor refrigerant charge, running conditions and optimise efficiency.

    When it comes to designing energy efficient cooling and heating systems, Star is a natural innovator. Star works with strategic partners across the globe to deliver low carbon, cost saving solutions.


  • Thermosyphon Chillers


    Freechiller from Star Refrigeration provides unrivalled efficiency for medium to large scale elevated water chilling applications (e.g. data centres). As ambient temperatures fall below the return water temperature ‘free cooling’ is available by ‘thermosyphon’ circulation of refrigerant around the chiller without running compressors.

    Freechiller annualised Coefficient of Performance (COSP’s) ranges between 10 to 15, depending on design temperature, chiller configuration and method of heat rejection. Generously sized heat exchangers coupled to high efficiency compressors and motors all contribute to reduce power consumption.

    Freechillers have a robust industrial construction using high integrity components that ensure a plant life in excess of 20 years. Studies of Freechiller installations have shown Life Cycle Costs typically 55% of standard chilled water systems using packaged air cooled HFC chillers. Additionally, use of ammonia allows the installation to be 'futureproofed' and avoids the risk of uncertainty about future use of HFC synthetic (global warming) refrigerants.

    Major financial and government institutions have deployed Freechiller systems for over 20 years to provide efficient, reliable cooling in their data centres. These sites have a high continuous base heat load 24/7, which benefit from low energy consumption and unrivalled resilience Star’s Freechiller delivers. Over 3,000,000 operation hours have been attained without loss of cooling.

    The chillers are typically connected in series in the water circuit to allow them to change operating mode and run independently for optimum system efficiency. The switch to thermosyphon operation is made by simply rotating a 3-way ball valve on the refrigerant side to bypass the compressor. Telstar control system manages this transition automatically and maximises the system run hours in ‘free-cooling’ mode. There is no need for large water diverting valves and additional heat exchangers that are incorporated into other ‘free-cooling’ chillers. Offsite monitoring of the system can also be provided.

    The water circuit has the chillers connected in series to allow each unit to change operating mode when ambient temperatures allow. Standby chillers are normally installed which act as back up mechanical capacity when required and also enhance the annual ‘free-cooling’ run hours.

    Individual Freechiller capacities start from 300kW, with large multiple chiller systems up to 5MW installed. Air cooled and evaporative condensers are available. The wet cooling systems are best suited to larger chillers with space constraints and offer the largest energy savings. Freechiller has low maintenance requirement since they have less compressor run hours than standard chillers.

    Star Refrigeration is the UK’s largest independent industrial refrigeration engineering company. Star focuses on the design, manufacture, installation, commissioning and maintenance of industrial refrigeration systems.

    Star offers a turnkey package to all users of refrigeration plant. Established in Glasgow in 1970, the company provides fast response 24-hour technical support from a network of nine branches to customers throughout the UK.

    Star's technical advisory arm, Star Technical Solutions (STS), operates as an independent consultancy providing advice on refrigeration engineering issues. Star also owns food freezing and chilling equipment specialist Starfrost, as well as mechanical and electrical contractors Penec.