CO2 is a natural refrigerant which is manufactured as a by-product from many industries. It is contained in large amounts in the oceans, and all living things produce or absorb it. Advances in technology are allowing engineers to design innovative ways to use CO2 as never before, making it a cost effective and sustainable replacement for traditional synthetic refrigerants.
R22, also known as HCFC-22, has been commonly used in air conditioning and refrigeration systems in Australia since the 1990s.
Releases of R22 into the earth’s atmosphere, including those from leaks, contribute to the depletion of the earth’s ozone layer.
As a result, Australia has a legislated phase out of all HCFCs in line with its obligations under the Montreal Protocol on Substances that Deplete the Ozone Layer. Australia will largely phase out the import of HCFCs from 2016, apart from the equivalent of around 45 tonnes of R22 a year.
The reduction in import quotas has seen a steep rise in the price of HCFC-R22 to around $395.00 per Kg (list price)
In 2017 the Australian Federal Government amended the Synthetic Greenhouse Gas Management Legislation to include the phase out of HFC refrigerants.
A statutory 85 per cent phase-down of HFC imports will commence from 1 January 2018. The phase-down will have a starting point of 8 Mt CO₂-e, based on Australia’s current demand and reduce to 1.6 Mt CO₂-e by 2037. The phase-down will be managed by import quota limits which will reduce every two years. 90% of quota will be allocated to existing importers and the remaining 10%will be allocated to applicants through a ballot system or by Ministerial discretion.
The reduction in import quotas has seen a steep rise in the price of HFC refrigerants similar to those seen with the phase out of HCFC-R22.
HFO refrigerants are been developed as a replacement for HFC refrigerants. Their operating characteristics are very similar to the HFC’s they’re intended to replace. The chemical process to manufacture HFO is extremely complex raising questions about the eventual cost per Kg. There are also concerns relating to their environmental impact, as when HFO’s breakdown in the atmosphere they produce Trifluoroacetic acid (TFA), which is extremely harmful to aquatic life.
Additionally, HFO’s, depending on their GWP, can be flammable and/or toxic.
When installed correctly and with the right safeguards, ammonia is a very efficient refrigerant, especially in large industrial applications. Due to its toxicity, however, ammonia has been at the center of a number of incidents that have led to loss of life, and as a result, there are grave health and safety concerns surrounding its ongoing use in the modern workplace. Additionally, ammonia systems generally require large capital investment due to the nature of the infrastructure involved. .
Although CO2 operates with high pressures, it is an excellent refrigerant in terms of efficiency and environmental impact. CO2 system technology has been widely adopted in Europe, Australia and gaining in popularity in the USA. Adapting CO2 systems in warm climates can be a challenge but huge in roads have been made in the development of new technology that enables CO2 systems to operate efficiently in warm climates.
In general natural refrigerants such as CO2 offer the best long term pathway. At Glaciem we believe CO2 is the future of refrigeration and we are considered industry leaders in its safe and efficient application.
The recent volatility in global and domestic energy markets is driving a fundamental rethink in how we access and use energy. Electrical battery solutions are now giving people the opportunity to store energy captured now, for use later. This makes sense if an electrical end use exists, but what if that end use was cooling? What kind of battery allows us to store energy now, to give us highly efficient ‘cold’ later?
Answer – Glaciem’s Thermcold. A revolution in ice or thermal ‘battery’ technology.
Thermcold’s groundbreaking Phase Change Material and Dynamic Melt system allow users to shift the energy load from the high daytime electricity rates to the lower nighttime electricity rates. How? Simply by recharging the Thermcold unit when energy is at its cheapest, and then using this stored ‘cold’ instead of the grid during peak times. This can reduce refrigeration electricity costs by up to 50% by charging during non-peak hours to discharge during peak-cost hours. Thermcold units are approximately 36% of the installed cost electrical storage (Batteries) and it makes sense to use the lowest cost option.
Additionally, flexibility around when to run refrigeration means cooling can run at night, using less energy due to lower ambient temperatures.
Exciting hybrid energy systems are made possible through Thermcold technology. Its energy storage capability resolves the mismatch between generation hours and electricity use so that solar and wind power can form an even larger slice of the national generation grid. Making ice with the sun and the wind!
This same flexibility can help smooth out electricity use, reducing the need for expensive, peak-driven infrastructure, and for extra fossil-fuel generation of power during daylight hours. This reduced ‘peakiness’can in some cases lead to reduced maximum demand (kVA) electricity supply charges and reduce the risk of receiving penalties for exceeding allowable total (kVA) demand.
Thermcold’s thermal storage system can also form part of a robust blackout management system. When combined with minor electrical storage to manage control systems, pumps and lighting, a combination of a renewable energy source and Thermcold thermal storage technology can allow sites to manage during periods of grid outage, helping avoid food or other perishable losses.
Phase change materials (PCM) are substances that absorb and release thermal energy during the process of melting and freezing. When a PCM freezes, it releases a large amount of energy in the form of latent heat at a relatively constant temperature.
The most commonly used PCM is water/ice. Working closely with the University of South Australia, Glaciem is on the cutting edge of PCM research and development. Advances in the composition of these materials are allowing Glaciem’s Thermcold ice battery technology to deliver reliable cooling at temperatures far outside the typical thermodynamic limits of water/ice.
Thermal energy storage (TES) allows the transfer and storage of heat energy, by means of a thermal reservoir. The thermal energy stored can then be used later. A typical example used for cooling is to run a refrigeration plant overnight using cheaper off peak electricity, then during the day the refrigeration plant is cycled off and the energy used in the ice is used for cooling, thus avoiding using more expensive peak electricity. Glaciem’s thermal energy storage solution, Thermcold, makes use of special phase change materials to allow thermal storage at previously unheard of temperatures.
Glaciem Cooling Technologies thermal storage system Thermcold utilises the development of new Phase Change Materials (PCM’s) to provide a revolutionary breakthrough that can significantly reduce energy costs for medium & low temperature refrigeration applications.
These special Phase Change Material (PCM)PCMs were devolved developed by UniSA and won winner of the Australian Museum 2015 ANSTO prize for Innovative use of Technology.
The technology has been fully commercialized by obtaining an Australian government CleanTech grant in 2013 and a 3200kW/h Thermal Energy Storage (TES) system has been operating successfully at an Onion and Potato storage facility in South Australia.
You can read more in our Parilla Case Study.
Medium & low Temperature Food Storage (0⁰C to -21⁰C) using secondary heat transfer fluids.
Thermal Battery; Potential to store excess electricity generated by Solar PV or Wind in the form of thermal energy
Ideal for increasing winery refrigeration plant efficiency at low loads outside vintage
Ideally suited for food process requiring –6⁰C glycol temperatures
Temperatures < -35⁰C Case studies have shown that CO2 has very high efficiencies in temperature applications below -35⁰C even out performing ammonia.
Blast Freezing
Plate Freezing
Spiral Freezing
Temperatures -18⁰C –to -25⁰C
CO2 used in applications between -18⁰C to -25⁰C demonstrates an increase in energy efficiency >20% when compared to R507 & R404A
- Food Storage/Distribution centers
- Supermarkets
- Pharmaceutical
- Process Cooling
- Beef Industry
- Fish Industry
- Poultry Industry
- Ice Rinks
- Ice Production
