Natural Refrigerants

«Naturally cool» provides fascinating insights and interesting information about the use of natural refrigerants. The filmlet uses illustrations to explain how the use of natural refrigerants has developed and their history since 2,000 BC. It reveals how natural refrigerants have found their way from ancient Egypt to our modern refrigerators.

Natural Refrigerants – between tradition and future

Natural refrigerants such as ammonia or carbon dioxide have a long-standing tradition – especially in food production and storage, where they have been in use for over 100 years. Did you know that the first shipment of frozen meat took place in 1873, when James Harrison installed a vapour compression refrigeration system on a sailing ship to send frozen beef from Australia to the United Kingdom?

In more recent times, technological evolution and innovations have helped to establish natural refrigerants economical and safe solution for new fields of application – the sports industry, recreation sectors, hospitals or pharmaceuticals and the automotive industry. Thesenatural refrigerants include ammonia, carbon dioxide, hydrocarbons such as propane, propene and iso-butane, water and airNatural refrigerants are both ecologically sustainable and economically viable - in short:the future of refrigeration technology.

Did you know that the first shipment of frozen meat took place in 1873, when James Harrison installed a vapour compression refrigeration system on a sailing ship to send frozen beef from Australia to the United Kingdom?

Nature as Developer

Ammonia, hydrocarbons, carbon dioxidewater and air – alof these natural refrigerants occurin nature's material cycles without human interferencehence the term “natural”. Ammonia constitutes an interesting case: While it is manmade for use in the refrigeration process, ammonia is nonetheless a natural refrigerant – since it occurs in nature in this form, such as the natural nitrogen cycle or in people's daily perspiration.

Natural refrigerants such as carbon dioxide are set apart from synthetically produced refrigerants, which fall into three groups: The first group are the so-called chlorofluorocarbons (CFCs and HCFCs), which have ozone depletion potential. The second group consists of fluorocarbons (FCs and HFCs) – while they do not harm the ozone layer, some of them have a considerable direct global warming potential (GWP). The third and newest group are co-called Hydrofluorolefine (HFO), which have neither ozone-depleting potential and only low global warming potential, but seem to have a negative effect on the environment, particularly water, although this is not fully investigated.


Ammonia Case Study - Natural refrigerants

Presentation of Monika Witt: ‘Natural Future’

Unbeatable climate protector and economic saver

In the light of global efforts for climate protection, there is a vital interest in natural refrigerants. Because – unlike some synthetic refrigerants – they do not deplete the ozone layer and have a negligible effect on the direct greenhouse effect. Thanks to their great efficiency, natural refrigerants do not contribute much to the indirect greenhouse effect – a fact that is confirmed in comparative calculations using the Total Equivalent Warming Impact (TEWI)-method.

The use of natural refrigerants is also well worth it from an economic viewpoint: The refrigerants themselves are very inexpensive, which has a positive effect not only on the initial charge of a plant, but also, from a leakage point of view, on the operating costs. In addition, natural refrigerants are highly efficient, which keeps the energy requirement of a plant low.

Depending on the type and size of the system, the investment costs of plants using natural refrigerants may be higher – but by the same token, these are offset by reduced operation costs. In efficiency studies spanning several years, natural refrigeration plants are often several steps ahead of their competitors. Reasons include lower leakage-related costs, the low cost of maintenance, as well as – and this is particularly relevant for industrial plants – their low energy consumption. Add to this the relatively inexpensive disposal of natural refrigerants at the end of a facility's service life – you have product that is beyond comparison. In other words: natural refrigerants are unbeatable – from an economic as well as an environmental point of view.