The ATMOsphere Review Board has announced the final round of case studies selected for presentation at the 6^th ATMOsphere Europe conference. Carrier, Danfoss, Embraco, Mitsubishi Heavy Industries, SINTEF Energy Research and Johnson Controls will present their innovative natural refrigerant technologies and projects at the event.

Commercial refrigeration

Barriers and opportunities for selection of best low GWP technologies by Torben Funder-Kristensen, Danfoss

The F-Gas regulation will increase the usage of low GWP solutions in general, but especially in supermarkets. The legislative pressure will accelerate a renewal of old installations towards applicable low GWP solutions. This means that the market and the service sector must be ready for producing installations with new technology, which is a fantastic opportunity for making efficient and climate friendly systems. However, if the market is not aware of the real challenges it faces, there is a risk that less efficient solutions will be selected.

In recent years, developments in CO₂ technology have continuously pushed efficiency limits and application opportunities. New components and systems are being tested with success in several supermarket test sites in Southern locations. Extended systems with heat recovery also show a very good business case. This case study will discuss factors influencing the choice of technology (short term – long term parameters) and potential pitfalls beyond the F-Gas Regulation (obey bans but sacrifice energy efficiency). It will provide a comparison between low GWP solutions for supermarkets (6 different ways to fulfill the demands of the ban) and highlight cases to show the available opportunities (heat recovery + results on ejector technology test sites). Factors influencing the technology choice are important to discuss because the energy agenda is also shifting alongside with the introduction of new refrigerants. There is a risk that more short-term solutions will be chosen, thus missing out on the opportunities for higher efficiencies.

Low global warming alternatives for ultralow cascade applications by Marek Zgliczynski, Embraco

For many years, Embraco has actively promoted the use of hydrocarbons in hermetic compressors. Apart from isobutane in household type appliances, significant progress has been made in the implementation of propane in light commercial plug-in systems. Even if not included in the new EU F-Gas regulation, cascade ultralow appliances can be easily modified to use hydrocarbons, thereby reducing their environmental impact.

In ultralow biomedical cascade applications, highly polluting substances are currently used. Embraco’s case study will show how to convert present -86°C applications into products with low environmental impact by using hydrocarbons in both system stages. The case study will highlight a unique compressor product line for ultralow cascade applications.

Italian supermarket: R744 multiejector enhanced parallel compression system by Armin Hafner, SINTEF Energy Research

According to the IPCC/TEAP, the annual refrigerant leaks from commercial refrigeration units related to the total charge are between 15% and 20% in Europe and -30 % outside Europe. Phasing out the current H(C)FC systems in the near future with efficient systems applying natural working fluids would result in a significant reduction of the environmental impact of commercial refrigeration. Several actors have aimed special R&D efforts at the development of high efficiency R744 commercial refrigeration systems. The use of expansion work in combination with flooded evaporators has shown itself to be the key to outperforming current H(C)FC systems even in high ambient temperatures.

A new supermarket located in the Trento province in Italy was commissioned in September 2014. The supermarket is equipped with an ejector supported R744 parallel compression unit, which is also able to perform 100% of the AC load supplied with the ventilation system. This case study will describe the system and first measurements. It will also provide a comparison of various R744 ejector technologies applied in supermarkets.

Heat pumps

CO₂ heat-pump water heater for commercial use by Shigeru Yoshida, Mitsubishi Heavy Industries (MHI)

Mitsubishi Heavy Industries (MHI) will present its two-stage compressor for commercial CO₂ heat-pump water heaters. Employing the world’s first combination of rotary and scroll mechanisms and intermediate gas injection, it realised high reliability and high efficiency under a wide range of conditions. The Q-ton, a commercial CO₂ heat-pump water heater equipped with the developed compressor, achieved a significantly improved heating capacity and COP and made it possible to introduce heat-pump water heaters in cold regions, which has always posed difficulties. On the actual site , the energy costs were reduced by the approximately 50%. In this case study, MHI will discuss the product and the actual energy-saving results. As a real site example, MHI will highlight cases of a hotel, a factory and a care home for elderly.

High temperature water vapour heat pump by Paul De Larminat, Johnson Controls

High temperature heat pumps using ammonia are available for temperatures up to about 90°C. At higher temperatures, only synthetic fluids like HFC-245fa or possibly new generation HFO’s were thought to be usable. Previous theoretical studies have shown that water vapor is a very attractive fluid beyond 100°C, but, so far, the implementation was stumbling on complex technological issues. These difficulties have been tackled and a prototype has been built and tested. It uses a two-stage centrifugal compressor directly driven by a high speed motor on magnetic bearings. It is designed for 700 kW heating capacity at 90°C evaporation and 130°C condensation. It was successfully tested for several months, showing excellent reliability and performance with a COP of 5.5 at design conditions.

The compressor can be included in a closed circuit with heat exchangers, or used for direct vapor re-compression. The presentation will highlight cases where this technology can be implemented, for example in drying and concentration processes. A future commercial range will cover heating capacities in the range 500 to 3500 kW. The case study presents both the technology and results, together with the perspectives for a future product range.

Other applications (transport refrigeration)

Efficient and sustainable transport refrigeration unit using CO₂ by Lionel Pourcheresse, Carrier

Since the early stages of the new F-Gas regulation discussions, Carrier Transicold has supported the introduction of a general HFC ban, as well as the introduction of regular mandatory leakage checks for refrigerated trucks, trailers, vans and containers. As the new F-Gas policy enters into force now, Carrier Transicold trusts that the new measures, in particular the HFC bans in certain sectors, will open up market opportunities for a wider uptake of climate friendly natural refrigerants.

Already in 1998, Carrier selected the E-Drive concept for its trailer solution, with natural refrigerants in mind as the E-Drive technology allows for the use of a fully hermetic refrigeration circuit, a mandatory step for switching to a CO₂ close loop system. In 2011, Carrier Transicold launched the NaturaLINE™, natural refrigerant technology for container refrigeration. In 2014, together with Sainsbury’s, Carrier began field trials of the first trailer refrigeration system based on a NaturaLINE™ unit. For over a year now, the unit has operated successfully, transporting frozen food with an extremely high level of reliability, efficiency and performance.

During the IAA 2014, Carrier Transicold presented a new E-Drive natural refrigerant trailer prototype. The Natural Refrigerant Trailer refrigeration prototype is a refrigeration unit dedicated to road transport using natural refrigerants in a closed-loop system. It is also fully autonomous as it is driven by an independent diesel engine. The system is simple for the user because it works in the same way as the legacy system: the product is charged at the factory with a defined amount of R744, which stays inside the refrigeration circuit. It is compressed then expanded and compressed again in a closed loop system. The benefit for the user is that there is no need to recharge the system every day, nor is there a need for heavy infrastructure to store the natural refrigerant. The Natural Refrigerant Trailer refrigeration prototype helps users to achieve their carbon footprint reduction target by reducing the impact of the refrigeration system without compromising on reliability or performance. Even if the system price is initially higher than current or partially improved systems (GWP less than 2500), the leakage check costs, taxes on refrigerants and refrigerant price versatility are factors that will not impact natural refrigerant systems, which increases the competitiveness and viability of using natural refrigerants.

About ATMOsphere Europe 2015
16 & 17 March 2015 at the Crowne Plaza Le Palace Hotel in Brussels, Belgium

The meeting place for leading HVAC&R industry experts to discuss the latest natural refrigerant technologies, market trends and policy issues is back for its 6th edition. To find out more about programme highlights, please visit www.ATMO.org/europe2015/prgramme.

Te register for the event, please visit www.ATMO.org/europe2015/registration