Question 1 – It’s said that refrigeration is the single largest energy user in a catering kitchen (i.e. think typical restaurant/pub kitchen serving 75-120 covers). What’s the single biggest thing that can be done to keep the refrigeration running costs down?
Answer – An interesting question to start with Andrew, yes it is very clear that electrically powered refrigeration equipment operating for 24 hours per day 365 days per year has the potential to consume a considerable amount of energy.
In this context the single biggest thing that can be done to keep refrigeration costs down is simple, we must use less energy within our refrigeration systems to reduce both running costs and also carbon emissions.
Hence any refrigeration system upgrade or refurbishment must be designed to use less energy and hence reduce costs, we must not simply replace existing equipment on a like for like basis without understanding how increases in refrigeration efficiency can be cost effectively achieved.
For example, technology has moved forward considerably over the last few years and it is now highly practical and cost effective to utilise the free waste heat from a catering refrigeration system to produce hot water for the kitchen. Integrating this type of waste heat recycling system provides immediate savings by displacing the costs of gas or electric heating, the energy to make hot water is constantly produced by a refrigeration system but is currently sent to waste!
Question 2 – What aspects/features of a foodservice refrigeration system most determine how energy efficient it is actually going to be?
Answer – If we are using energy to chill or freeze product we must use the lowest amount of energy possible to achieve our objective. This means that the refrigeration system must be correctly specified and designed to match the needs of the application, ‘refrigeration specification is definitely not a one size fits all procedure’.
The cold room itself must be of adequate specification in terms of providing the highest level of practical insulation to reduce the cooling demand, but more importantly the 24/7/365 energy consuming electrically powered refrigeration equipment must be efficient and correctly specified.
The specification of the refrigeration design must take into account the demands of the application and match these demands with the most efficient system available.
A good example of this approach would be to look at a kitchen with three coldrooms and to consider the specification of a single centralised refrigeration system instead of three separate individual refrigeration units.
The single centralised unit would have the capability to operate efficiently on minimum load with an inverter driven compressor system (modulating to very efficiently match the actual cooling load of each coldroom), this design can provide energy savings of over 20% per year in comparison to the three individual stand alone refrigeration units and this is achieved simply by minimising unnecessary energy use by good design.
Question 3 – When looking to specify/install the most energy efficient refrigerated storage systems into their kitchen, what are the first things that an operator needs to do or bear in mind?
Answer – Whether the project is a retrofit or new installation an operator has the opportunity to make real energy savings by selecting a refrigeration system that reduces energy use.
In order to ensure that the operator receives best advice it would be advantageous for them to work with a specialist refrigeration designer who has an in depth knowledge of current technologies and importantly has the ability to apply the technology within a practical and cost effective system design.
With regard to design options, each of the potential systems return on investment must be understood and any opportunity to achieve tax savings from the installation of energy efficient equipment must also be considered, for example a 100% tax allowance of the equipment’s capital cost could be available in the first year.
A full understanding of the kitchens refrigeration demands must then be made clear, a kitchen refrigeration energy survey would obviously include the cooling requirements but also the kitchens hot water requirements as the objective of any project should be to achieve the maximum level of efficiency from the cooling & heating system as a whole by recycling the free waste heat from refrigeration to provide hot water.
Once the operator has a clear picture of the available refrigeration options they will then be able to make an informed decision as to the best system for their particular application.
The most important point that I would emphasise here is that the operator must be made aware of current technologies and their practical benefits, cost savings can be achieved but also carbon reductions can also be achieved from selecting proven low energy systems.
However if the operator is not aware of these low energy systems then they cannot be applied, hence it is vitally important that the benefits of energy saving refrigeration plant are understood fully by the operator.
There has been a high level of development within the world of food service refrigeration over the past five years, however it is quite common to see equipment being replaced by a contractor on a ‘like for like basis’ without any consideration of developments in technology, which is really not good enough in todays world where energy saving has to be a priority.
This is where a specialist refrigeration design house can add real value as they will have the in depth knowledge and application experience to propose the most suitable equipment & system design options.
Question 4 – What’s the most innovative project you’ve been involved in to bring refrigeration costs down (and efficiency up) for a foodservice/restaurant end-user? (In a nutshell how did you achieve a successful result?)
Answer – We work on a large number of food service refrigeration projects each year across many sectors providing a complete design & installation service.
But as the name ‘Green Cooling’ suggests our focus is on providing the most practical, efficient and environmentally sustainable refrigeration systems.
However in terms of project highlights we are particularly pleased that our CO2 Twin Energy system won one of the refrigeration industries most respected awards in 2015 for Innovation in Food Service Refrigeration.
The award was based around an application of our technology in Canary Wharf where we designed and installed centralised medium and low temperature multiple inverter driven refrigeration systems with the simultaneous production of 65C hot water.
This 65C hot water is accumulated 24/7 within a thermal battery in order to provide the highest level of savings possible from the recycling of waste heat from refrigeration i.e. storing overnight-recycled refrigeration waste heat/energy for daytime use.
This system is relatively large in terms of capacity but the design & operation of a waste heat recycling system is completely scalable, hence we now have smaller capacity retrofit systems available.
Our challenge now is to communicate the energy saving benefits that are available from these refrigeration systems and encourage acceptance within industry.
Question 5 – An operator that is planning to invest in a greener refrigeration solution now will also want it to last for the next 5-10 years at least. What is your advice on how they can ‘future-proof’? (i.e. is there any forthcoming legislation, technological changes etc in the refrigeration industry they should bear in mind with regards to the future?)
Answer – This really is one of the key questions Andrew and could easily fall into the ‘the elephant in the room’ category.
Our discussion has so far revolved around reducing energy use, which is definitely the highest priority area of focus for an operator.
However it is also vital that an operator understands the unique period that the refrigeration sector finds itself in at the current time.
From now until 2030 there will be an accelerating worldwide focus on removing ozone-depleting refrigerants from all industries & applications (the refrigerant phase out).
So what does this actually mean to an operator…?
Put simply this means that refrigeration equipment could be installed now and during its operational life (to allow it to remain functional) it could require costly and time-consuming modifications or at worst become obsolete due to the refrigerant used within the system being phased out.
Because the refrigerant used within a new system that is installed today may already be on the refrigerant phase out list and may have a defined period of use, or the refrigerant could be accelerated further along the phase out list during its operational period of use because it is a high ozone depleting refrigerant.
The phase out is geared towards removing high ozone depleting refrigerants and a number of these are used within food service refrigeration systems.
So how can an operator ‘future proof’ their installations…?
Simply by selecting a system with a refrigerant that does not present the risk of phase out.
For example we design & install a large number of systems utilising the natural refrigerant CO2, which cannot become part of the refrigerant phase out process basically because CO2 is a natural refrigerant and is not chemically based.
However there are other low impact refrigerants which can still be specified, but it is vital that an operator gains specialist application knowledge in order that they are able to ‘future proof’ the operation of a high capital cost refrigeration installations.
Taking the point that we mentioned earlier, with regard to refrigeration we can no longer install what we have always installed or simply replace on a like for like basis.
Low energy and sustainable refrigeration systems must now be considered for practical and common sense operational reasons.