STS Case Studies

Brakes Group is a major fresh, grocery & frozen food supplier to pubs, restaurants, education and other catering industries in the UK & Ireland. The Star Refrigeration Group has provided new refrigeration systems and on-going operational support to the business for over 25 years. Brakes continue to see strong growth, both organically and by acquisition, and part of its strategy for this is the development of a number of new DC’s in the UK.

STS was commissioned to carry out a feasibility study reviewing a range of refrigeration system options for this next generation of Brakes DC’s. A key stipulation for the feasibility study was that ammonia (R717) was to be used as the primary refrigerant. The study reviewed three options in detail:

1. Central, 2-stage pumped R717 plant sending R717 to all coolers.
2. Central 2-stage pumped R717 for the cold store and an R717 / glycol side load taken at the interstage condition. Glycol will be pumped to the Chill Store and LoadingBay.
3. Direct R717 to the cold store – modular, flooded operation, reverse cycle plant – and pumped glycol, operating with flooded R717 glycol chillers for the chill store

The analysis included a life cycle assessment, based on Nett Present Value analysis, covering: capital, energy, water, maintenance & replacement costs. The system selected was Option 3, which delivered the best balance of capital and operational costs coupled with a very low ammonia refrigerant charge, a key H&S factor for Brakes.

Following on from the feasibility study STS was incorporated into the Brakes project team taking the findings of the study and preparing the detailed technical specifications for the insulated envelope and refrigeration systems. STS responsibilities include reviewing tender submissions from prospective contractors, attendance through the project construction phase and final approval of the insulated envelope and refrigeration systems.

There will be three new DCs built by 2014, in the south, centre and north of the country. Each DC will be circa 185,000m3 in volume with multi-temperature facilities at

-21^oC , +1^oC, +8^oC & +14^oC, as well as an ambient area. The main insulated chambers are internal insulated systems supported by an external structure, ie a “box-in-box” design, using high performance composite insulation panels incorporating PIR insulation.

CPD Presentation

A full CPD certified presentation of Brakes Brothers and Ammonia Savety with Low Charge Refrigeration Systems is available HERE.