Star’s Low Charge Ammonia Chillers Catapult Snozone’s Savings on Electricity and CO2 Emissions

Alan Walkinshaw
Special Projects Sales Manager

Star Refrigeration’s ultra-efficient low charge ammonia Azanechillers 2.0 helped future proof Snozone’s business for the next 20 years.

Snozone Milton Keynes, one of the UK’s top indoor leisure attractions, is celebrating improved usage, profitability and functionality following the installation of Star Refrigeration’s latest air-cooled Azanechillers 2.0.

The UK’s leading refrigeration manufacturer, Star Refrigeration, have helped Snozone save a substantial 56% on electricity bills and achieve a drop in emissions of 700 tonnes of CO2, in only four months, thanks to the exceptional efficiency of the Azanechillers 2.0 which exceeded Europe’s Eco-Design Minimum Energy Performance Standards (MEPS) requirements by 80%.

The Snozone facility contains 1500 tonnes of snow and ice which have to be maintained at -4˚C air temperature for optimal operation, and the new refrigeration plant uses less energy to produce better skiing conditions. Keeping the environment cool at Snozone is crucial for business, but the building’s previous refrigeration plant was struggling with summer ambient temperatures and a temporary chiller plant was required regularly to support it on a seasonal basis.

Hulley & Kirkwood, consulting engineers, designed a strategy for improving the cooling plant while maintaining business continuity. It was essential to ensure long term reliability and economic efficiency, and Star’s reputation as the industry’s leading refrigeration experts led to the company being contracted as part of the strategy. An innovative new refrigeration plant installation by Star Refrigeration, which uses ammonia as a refrigerant, has improved efficiency and safeguarded the facility for the future.

Kyle Bell, Snozone’s Operations Director said, “We have two indoor snow centres, and at our Castleford venue we operate with an ammonia based cooler system. We’ve had a good experience with ammonia in this location and found it extremely reliable, and therefore decided it was time to do the same at Snozone Milton Keynes.”

Star Refrigeration and Hulley & Kirkwood have successfully worked together to deliver this project and achieve incredible savings and benefits for Snozone since the 2017 installation. However, there were challenges to overcome – including the setback of the existing plant room being unsuitable for an ammonia plant. The car park was an impractical location so another outdoor location near to the existing plant room was found. Also, in order to identify all safety measures required for installation of the new outdoor packaged ammonia chillers, specialist refrigeration consultants Star Technical Solutions carried out an Ammonia Hazard Assessment.

The location of two 9.7m long chillers on the paved area outside the plant room required careful surveying to ensure that they did not obstruct any underground services or impact on traffic movement or parking adjacent on the site access road. A louvered perimeter wall was specified to screen the chillers from public access that also allowed adequate air flow onto the air cooled condenser coils. It was also necessary to conduct noise surveys as a new hotel was being built close to the building.

The original R404A chillers were replaced with two Star AA415MTE-1 Azanechillers 2.0 rated for 360kW capacity chilling ethylene glycol from -10 to -13C. Vahterus plate and shell evaporators allow a close refrigerant approach while minimising ammonia charge to only 85kg per chiller. Acoustic enclosures around the compressor/motor assembly combined with EC condenser fans present the lowest noise outlay possible for the retrofit installation.

With HFC refrigerants such as R404A being phased out and banned by 2020, it is important for businesses to consider the use of natural refrigerants such as ammonia which have zero global warming potential.

The new ammonia installation has been transformational for the Milton Keynes venue. Alan Walkinshaw, Sales Manager –Special Projects at Star Refrigeration explains, “The new equipment has been easily able to maintain
-13C glycol temperatures in the ski slope even on warmer days, whereas the previous equipment was struggling to achieve -8C at peak times. However, the plant isn’t necessarily working harder than the previous system, it is just more efficient. Energy savings have been dramatic, with a 56% saving on electricity in the first four months of operation – from 1,511,062kWh to 661,255kWh for the same period in 2016.”

Thanks to the upgraded system, Snozone can continue to offer its world class indoor snow activities – future proofed- for the next twenty years.  Snozone can uphold its status as one of the UK’s best facilities for snowsports, attracting millions of ski enthusiasts, snowboarders and families looking for a fun day out.


To find out more about Star Refrigeration’s ammonia Azanechillers 2.0 visit: /

For information about Snozone go to:

Star’s Low Charge Ammonia Chillers Catapult Snozone’s Savings on Electricity and CO2 Emissions

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