Brewing and Distilling Case Studies

  • Guinness Brewery Dublin

    Cooling specialist Star Refrigeration has completed a major project for RWE Solutions at Diageo’s Guinness production plant in Ireland.

    Diageo, the global leader in premium drinks, was looking to increase production of its world famous Guinness stout at the St. James’s Gate Brewery in Dublin. The company wanted to boost the production capacity of its brewing process plant and associated utility equipment to the equivalent of 12 million kegs per annum.

    A significant increase in refrigeration plant capacity was critical to the success of the scheme. It was essential that the upgrade of existing plant and additional refrigeration capacity required was achieved within a six-month programme of work, with minimal disruption to production.

    Star was contracted by RWE Solutions for the design and installation of a new industrial refrigeration system for the Guinness plant. RWE Solutions is the energy services company which owns, operates and maintains all utilities equipment at the Dublin facility, including refrigeration, under a fifteen year contract.

    Star’s engineering team worked with RWE Solutions to conduct an extensive evaluation of the existing ammonia refrigeration plant and associated glycol system. The solution was to design and install 3.5MW of additional refrigeration capacity to work in conjunction with the existing plant. It was vital that the extended and upgraded plant operated with enhanced efficiency and environmental benefits.

    The refrigeration plant upgrade was completed on time and on budget. The plant provides a total of 8.9MW of refrigeration capacity at an overall evaporating temperature of -4.5°C. This increase in refrigeration capacity has been achieved without adding a significant increase in refrigerant charge. As well as providing an environmentally friendly solution, the new refrigeration system was designed to enhance overall operating efficiency and reliability.

    Star’s project and site management team worked closely with RWE Solutions and Diageo to ensure that installation and commissioning work were programmed to prevent disruption to the brewing process. Careful planning enabled the duration of four programmed shut downs to be reduced from two days to twelve hours. This enabled production to be maintained throughout the project.

    Star Refrigeration’s Managing Director Andy Pearson says: “The Guinness project demonstrates Star’s strength in applying best practice and new thinking to create a first class installation. Our engineering team worked in close partnership with RWE Solutions to improve and optimise a traditional refrigeration system with a high level of technical innovation. We were also able to ensure major site works were expertly managed and completed without disruption to production.”

    The new refrigeration plant comprises two Star compressor package units with twin-screw compressors and high efficiency drive motors. A new surge drum and two gravity fed plate heat exchanger evaporators were also installed to work alongside four existing shell and tube evaporators. Existing evaporator glycol pumps were augmented with three additional pumps complete with variable speed drives, to pump glycol through the plate heat exchangers. Extra condensing capacity is provided by an additional evaporative condenser.

    Star also introduced a new computerised control system to optimise plant operation and ensure accurate temperature control. The Telstar PLC system is integrated with the plant’s existing control system and is designed to improve system management, reliability and efficiency.

    On completion of the Guinness project, Star conducted comprehensive on site training for RWE Solutions’ engineering staff and advised on safety management procedures. Star will provide specialist refrigeration plant maintenance services on site to RWE Solutions as required in the future.

    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.

    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.

  • Thwaites Brewery

    Star Refrigeration has recently completed a project to boost capacity and reduce energy costs for Blackburn based brewer, Daniel Thwaites.

    Following previous successful projects replacing heat exchangers and separator vessels, Star replaced an existing reciprocating compressor and added additional plate heat exchanger cassettes to a modular cooling plant. This increased capacity from 310kW to 400k and reduced weekly running costs. This nett effect is a return on investment of less than 18 months.

    This improvement in efficiency comes from a combination of using an inverter controlled reciprocating compressor in place of the original fixed speed machine and installation on a new compressor sequencing system.

    A comparison of fixed speed and variable speed replacement options at the tender stage demonstrated the benefits of using a variable frequency drive (see graph 1). Daniel Thwaites recognised the operating cost benefits from investing in the variable speed option and these have been realised on site following successful plant installation and comparison.

    Further enhancement of performance has been achieved through the installation of a new compressor sequencing controller. This measures the secondary IMS cooling medium temperature and sequences starting/stopping of the new inverter driven compressor and two existing fixed speed machines.

    Power measure on site demonstrates average weekly savings of around £2,000 on site electricity costs (see graph 2) following installation of the new compressor and sequencer. This results in a payback of less than 18 months based on current energy cost.

    "The replacement of our ammonia compressor had the potential to cause issues with production from both a temperature and logistics perspective. The thorough and detailed project management carried out by Star meant that neither of these became and issue. Star’s attention to detail continued through the commissioning stage, right up to running in of the unit during the initial 3 months. Customer queries were dealt with quickly and advice on efficient operation has been essential to reducing our electricity costs, which have been greater than anticipated," - Thwaites Projects and Utilities Manager, Mick Cockshott.

    The Daniel Thwaites installation is just one example of energy enhancing solutions from Star Refrigeration. Others include:

    • Azanechiller - Air and water cooled high efficiency packaged chillers.
    • Aether – Condenser and pump inverter controller.

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