Background article

Switzerland: Top-class when it comes to natural refrigerants

In view of the revised F-Gas Regulation, the refrigeration and air-conditioning branch is looking to change over to environmentally-friendly and viable applications that are also economically profitable. Switzerland is a major pioneer in this respect. But what exactly has put the Alpine state in this position? Outstanding energy standards and legislation demanding sustainable refrigeration and air-conditioning solutions definitely play an important role. But a significant contribution also comes from the innovation commitment of planners, combined with great willingness on the part of operators to implement new technologies. Demanding legislation and trend-setting projects – in this portrait, eurammon shows why Switzerland has a tradition of advocating natural refrigerants.

Statutory restrictions for refrigerants impacting on the climate

In Switzerland, the Ordinance on Chemicals Risk Reduction regulates the use of substances said to be stable in air – volatile fluorinated hydrocarbons with a half-life period in air of more than two years. This includes nearly all fluorinated refrigerants apart from R-152a and many HFOs. A further tightening of the regulation means that since the end of 2013, there is also a partial ban on systems that run on refrigerants with high global warming potential. "Emissions from refrigerants impacting on the environment must be avoided as far as possible in technical and economic terms. To this end, we have adjusted the prohibitions according to current state-of-the-art engineering to make them demanding but still feasible", says Blaise Horisberger from the Federal Office for the Environment (FOEN). In practice, this ban affects industrial refrigeration systems above 400 kW, commercial refrigeration systems from smaller capacity ranges, air-conditioning systems and thermal pumps above 600 kW and also artificial ice rinks. "According to our estimates, the current regulation should result in natural refrigerants and HFOs accounting for about two thirds of the installed quantity of refrigerants in the long term", says Horisberger. "If natural refrigerants continue to be used with such success, there is a good chance that users in future will opt mainly for ammonia, CO2 and co."

Smart use of synergies: ammonia for refrigeration and heating

An altogether positive example for using natural refrigerants can be found south of Chur with Fleischtrocknerei Churwalden AG, a meat-drying company located at 1,000 metres above sea level. In order to make the most sustainable possible use of resources, the building has been successively brought in line with the very latest technical standards. To this end, the company also installed a new refrigeration system – of course with ammonia. "Many of our customers want a solution with natural refrigerants to ensure they can use their system in the long term – this also applies to Fleischtrocknerei Churwalden", reports Beat Schmutz, Managing Director of the eurammon member SSP Kälteplaner AG. Both heat energy and refrigeration energy is needed all year round to dry the meat, so that SSP Kälteplaner advocated an integral building concept that uses the waste heat from the new refrigeration system for heating and hot water. The waste heat from generating compressed air and refrigeration is collected in a large stratified storage tank that can hold 30,000 litres. From here, the waste heat is then distributed at selected temperatures to the individual distribution units. Fleischtrocknerei Churwalden is now almost in a position to manage without the old oil boiler system that used to generate most of the heat energy. It is now only used to cover peak demand. As a result, annual oil consumption has sunk by 70%. The massive reduction in CO2 emissions is similarly impressive. The new system saves a full 320 tonnes CO2, thus making a considerable contribution to climate protection.

Tradition of supermarket refrigeration with natural refrigerants at Migros

Energy-efficient, low-cost and kind to the climate: when it comes to commercial refrigeration, operators such as Migros, one of Switzerland's largest supermarket chains, show the way. Migros has been using ammonia systems and various CO2 solutions for both deep-freezing and chilling already since 1994. Today CO2 is the standard refrigerant, used in more than 370 systems at over 277 supermarkets – mostly as a CO2 booster system with waste heat exploitation. Numerous stores can only be heated by this waste heat. The reasons for the long tradition of systems with natural refrigerants are to be found in a holistic climate and energy strategy: "Our aim is to achieve a 20% reduction in direct and indirect emissions of greenhouse gases by 2020, compared to 2010", explains Urs Berger, Head of Energy and Building Systems at Migros. "In the end, direct greenhouse emissions can only be eliminated with a natural refrigerant such as carbon dioxide". Energy efficiency is just as important for commercial refrigeration. Here there has been a clear increase at Migros. Before introducing the CO2 technology, the target refrigeration index was 4,000 kW/m x a, which refers to the electricity consumed by the refrigeration system per system length in metres and year. "Meanwhile our current targets have fallen to between 2,000 and 2,700 kWh/ m x a, thanks to the efficiency of our systems", says Berger. Massive reductions in operating costs are another financial argument in favour of these systems. The specific CO2 safety requirements are fulfilled by the refrigeration system manufacturers and by the operators. "Every change in technology also entails a learning phase. The CO2 systems have proven their worth in practice and are reliable", emphasises Urs Berger.

First refurbished artificial ice rink in Minergie-Standard

Outdated artificial ice rinks in need of renovation pose a particular challenge. They need huge refrigerating capacity and often impose considerable space constraints on new refrigerating systems. The eurammon member acoenergy has faced up to this challenge in a current project and implemented the very strictest energy standards. The new refrigerating system for a regional ice sport centre in Switzerland's Central Plateau faces demands for maximum energy efficiency and low operating costs together with low investment costs. To this end, acoenergy developed a highly efficient, indirect NH3 system with a water/glycol blend as secondary refrigerant for cooling the ice rinks and a curling arena with a refrigeration capacity of approx. 1.2 MW. It will be starting operations in two phases in 2016 and 2017, resulting probably in reductions of up to 34% in energy and about 50% in CO2 emissions. The special thing about the refrigeration system is that it complies with the Minergie-Standard – a voluntary quality guideline for energetically optimised buildings that goes over and beyond the statutory requirements. 23 criteria apply to artificial ice rinks, including for example a minimum waste heat exploitation level of 70%, which has to be verified by means of detailed balance sheets. Provisional certification has already taken place and will be followed by a two-year optimisation phase to give operations the final polish in order to become top-class in energetic terms. "New-build projects for artificial ice rinks are primarily planned on the basis of this voluntary ecological standard", says Stephan Lutz from acoenergy. "Our refurbishment project will be the first of its kind."

Into the future with highest standards

Switzerland shows examples of how natural refrigerants can be put to successful use, while fulfilling the strictest energetic standards at the same time. "Switzerland plays this pioneering role because it has forged ahead with the use of natural refrigerants by systematically restricting refrigerants impacting on the climate. The refrigeration branch has taken up this challenge and operators also attach great importance to sustainable refrigeration technology", explains Urs Berger from Migros. In short, Switzerland has managed to meet the challenge of ever tighter statutory requirements – and is looking further ahead to the future. There is still great potential for huge reductions in direct and indirect emissions of greenhouse gases by using natural refrigerants, particularly in small capacity ranges, such as smaller refrigeration or heat pump systems.