Q. Which hydrocarbons can be used as a refrigerant? The following hydrocarbons can be used as a refrigerant in cooling & heating applications:

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1 Basic Facts About Hydrocarbons Q. What are hydrocarbons? Hydrocarbon refrigerants are environmentally friendly, non-toxic, non-ozone-depleting replacement for chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs). From a chemical point of view, a hydrocarbon is the simplest organic compound, consisting entirely of hydrogen and carbon. Hydrocarbons (HC) are naturally occurring substances. The majority can be found in crude oil, where decomposed organic matter provides an abundance of carbon and hydrogen. Q. Which hydrocarbons can be used as a refrigerant? The following hydrocarbons can be used as a refrigerant in cooling & heating applications: R170 - ETHANE - C 2 H 6 R290 - PROPANE - C 3 H 8 R600a - ISOBUTENE (Isobutylene, 2-Methylpropene) - C 4 H 8 R600a - ISOBUTANE (2-Methylpropane) - C 4 H 10 R PROPYLENE (Propene) - C 3 H 6 R ETHYLENE - C 2 H 4 However, the most commonly used HC refrigerants are propane (mainly in commercial and industrial freezers, air conditioning and heat pumps), and isobutane (in domestic refrigerators and freezers). Q. What are their main advantages? Hydrocarbons are one of the most climate-friendly and cost-efficient refrigerants to heat, cool and freeze: Non-ozone depleting: Ozone Depletion Potential = 0 Not climate damaging: Global Warming Potential = for most HCs below 3 Non-toxic Safe: with proper handling Energy-efficient: usually better energy efficiency than CFC or HFC systems Easy replacement: able to replace many F-gases in existing systems without the need to change components or oils Cost-efficient: low refrigerant purchase price as well as lower system running costs Q. Are hydrocarbons safe? Yes, with proper handling. Since hydrocarbons are flammable, some basic safety rules need to be respected by manufacturers, installers and users, which may differ slightly depending on the application. As long as these rules are respected, it is perfectly safe to use hydrocarbons as

2 refrigerants. Propane, for example, is used universally for heating and cooking. As a result, its safe handling is widely understood and practiced by the general global population. This makes it an appropriate alternative to climate damaging chemical refrigerants also in developing countries. Q. Are hydrocarbons flammable? Yes. However, keeping to the safety guidelines existing for any application using flammable refrigerants, the risks of using hydrocarbons can be kept to a minimum, hence avoiding any threat to human health and safety. Many components for commercial refrigerated appliances using hydrocarbons already meet safety standard requirements. Q. Are HCs toxic? No. Hydrocarbons are not toxic for human beings and other living organisms. Environment Q. Do HCs have an impact on the ozone layer? No. Hydrocarbons do not contribute in any sense to the depletion of the ozone layer. Q. Do HCs contribute to global warming? No. Most hydrocarbons used as refrigerants have a Global Warming Potential (GWP) of below 3, meaning they don t pose a threat to the earth s climate in small concentrations. By contrast, R404a, one of the chemical refrigerants hydrocarbons can replace, has a GWP of 3,260. To visualize this figure: 1 kg of released HFC-404a is heating up the atmosphere like 1.1 tonnes of propane or isobutane! Q. How does an HC system reduce greenhouse gas emissions? There are two factors involved: Firstly, using hydrocarbons reduces the Direct greenhouse gas (GHG) emissions. This is due to the low Global Warming Potential (GWP) of HCs of just 3, compared to a GWP of 1,410 for HFC-134a, and even higher values for other chemical refrigerants. Why is this important? As an example, from a typical supermarket refrigeration system 5 to 10% of the total refrigerant charge is emitted to the atmosphere every year. Assuming that leakage rates are the same, hydrocarbons will thus spare the planet tonnes of greenhouse gases compared to any other chemical refrigerant currently used. Secondly, HCs also lower the Indirect GHG emissions by maximising energy efficiency through a combination of factors, including their favourable thermodynamic characteristics, a higher Coefficient of Performance (COP), and a low condensing temperature. As an example, even when used in a secondary loop Mobile Air Conditioning system - to overcome any outstanding safety concerns - hydrocarbons (propane as the best choice in this case) would still represent a

3 net savings of at least 80% of greenhouse gas emissions associated with current HFC-134a systems. Q. Which chemicals refrigerants can be replaced by hydrocarbons? Hydrocarbons can replace many obsolete CFCs, HCFCs, and HFCs, including the ozonedepleting refrigerants R12, R13, and R22 in domestic, commercial and industrial refrigeration, and car air conditioning. It is also a future-proof substitute for R134a, R404a, R407c or R507a in fridges, freezers, cascade supermarket systems, heat pumps, and chillers. Moreover, hydrocarbons can replace harmful insulation foam blowing agents. The hydrocarbon cyclopentane is now used as a viable alternative in HC domestic refrigerators. Q. Where do the HCs used as a refrigerant come from? Hydrocarbon refrigerants are naturally occurring substances obtained when oil and gas are produced. They are easily available globally at the lowest costs. Q. Are HCs totally new refrigerants? No. Propane (R290) has a long history in refrigeration. It has been in use since before ozonedepleting CFCs were developed and was re-introduced for use in heat pumps after the CFC phaseout. Its thermodynamic data, efficiency, and material compatibility are well known. In some countries, appliance manufacturers and food producers began using R290 as a replacement for R404A or R134a in appliances shortly after 2000, due to environmental concerns. Q. How energy-efficient are HCs? Hydrocarbons are more energy-efficient than most conventional HFC or CFC systems. Used in residential air conditioning units, hydrocarbons have reported to be in the range of 20-30% more efficient that synthetic refrigerants. A CO 2 -propane cascade supermarket system can save around 5% of energy, compared to an equivalent R404a system. In Mobile Air Conditioning, studies hint at a 35% higher energy efficiency than HFC-based MAC. Field tests with large A/C chillers have shown that all energy efficiency measures combined can result in a potential energy savings in excess of 50% for chillers that operate year round when compared to minimum first cost chillers without energy saving features. Technology Q. In which applications are HCs used? Hydrocarbons are suitable for use in the following applications: Domestic Refrigerators & Freezers: By far the largest application for hydrocarbon refrigerant to date. For example, R600a (isobutane) is used in more than 300 million socalled Greenfreeze fridges and freezers worldwide.

4 Commercial Refrigeration: Mostly R290 (propane) is used as a replacement for the ozone-depleting substance R22 and HFCs in ice cream freezers & cabinets, commercial freezers & refrigerators (walk-in-freezers, meat freezer, salad coolers), ice cube machines, bottle coolers, vending machines, cascade supermarket refrigeration systems, or water coolers. Air Conditioning: Split AC for office and domestic use, portable AC, water-air AC, airair AC, AC chillers, and dehumidifiers can use hydrocarbons. Mobile Air Conditioning (MAC): As a retrofit for the currently used high global warming refrigerant HFC-134a, mainly drivers in Australia and North America are using HCs as a more efficient, cheaper alternative. HCs can work as a primary MAC system refrigerant, or in secondary loop systems to ensure a safer use. Some companies are using HCs for cooling the drivers compartments in buses. Heat Pumps: Propane (R290) can be used in water-to-water low-charge heat pumps. Q. How much do I need in different applications? A typical car air conditioning system contains about a coffee cup full of liquid refrigerant, and a small refrigerator contains about an eggcup full. An ice cream cabinet uses 100 g of HCs, half the amount needed of climate damaging HFCs. A mid-sized car with an HC secondary loop air conditioning would use 200 grams of propane. Split-system air conditioners for office and domestic use do not use more than 300 grams of HCs. Depending on the capacity, a heat pump could use from 500 g to 5 kg of propane. Q. How does a HC system work? A system using hydrocarbons works in exactly the same way as systems currently using synthetic refrigerants. The basic refrigeration cycle remains the same, and only the charge of the system (exact amount of refrigerant) varies. Q. Can I replace HFC systems with HC? Yes. Components for the ozone-depleting chemical refrigerant R22 (e.g. compressors) are massively available in the market. The hydrocarbon refrigerant propane (R290) can use the same technology and is compatible to the most commonly used heat exchangers and materials. It is therefore the most cost-efficient replacement for harmful substances in many commercial refrigeration uses. Compressors developed specifically for R290 have been available since No other single refrigerant than propane (R290) has such similar thermodynamic behaviour to R22. In high ambient temperatures, R290 performs better than R22 in terms of discharge temperature and pressure. This makes it the best replacement option for the ozone-depleting and high global warming R22.

5 Q. What are the major benefits of using HCs? The two main advantages of hydrocarbon refrigerants are lower environmental impact and economic gains. First, hydrocarbons do not damage the ozone layer. Moreover, hydrocarbons can significantly reduce emission from greenhouse gases of refrigeration and air conditioning equipment. Because of their very low global warming potential, their impact on global warming from direct emissions is much lower. Hydrocarbons lead typically to much higher efficiency than traditional chemical refrigerants, thereby reducing energy consumption and greenhouse gas emissions related to them. In terms of economic benefits, besides energy-related savings, hydrocarbons can be easily implemented in conventional cooling systems, requiring minimal investment in components and design. Legislation & Safety Q. Are there any legal requirements when using HCs? As hydrocarbons are classified as flammable in international safety standards, their use in charges of up to 150 grammes per systems must follow certain guidelines. Guidelines for designing appliances for flammable refrigerants are available to meet the safety standards at any time. They specify that appliance producers manufacturing HC systems must be equipped accordingly, and service technicians must be trained in safe handling procedures. Safety standards cover leakage simulation tests and specifications for the sealing of several electrical components which may come into contact with leaking HCs. There are international standards on electrical safety in place, for the following applications: household refrigerators and freezers, motor compressors, commercial refrigerators and freezers, heat pumps, air conditioners and dehumidifiers. However, a major problem for the global application of hydrocarbons is the lack of consistency from country to country, with some posing weaker or stricter legal requirements, and others still completely banning HCs from certain applications. The USA might serve as the best example of a world market currently in the process of lifting bans on the use of HCs in applications other than industrial process refrigeration. Q. Where can I not use HCs? At present, propane cannot be used in systems requiring charges of more than 150 grammes. This amount is considered to be safe if the appliance itself is tested for safety. There are no safety guidelines for units with a propane charge greater than 150 g. Economy & Markets Q. What are the key markets for HCs today? Domestic Refrigeration: By far, the biggest markets for HCs at the moment are domestic refrigerators and freezers. Isobutane is used in 100% of all new home fridges in Germany, and in 50% of all new Chinese models. HC refrigerators are also sold in Western Europe, Argentina,

6 Australia, Brazil, Cuba, India, Indonesia, Japan, Pakistan, and Russia. Overall, there are more than 300 million HC refrigerators running worldwide (2008). Commercial Refrigeration: Propane (R290) and CO 2 (R744) are used together in cascade supermarket refrigeration systems to provide high temperature and low temperature cooling for foodstuff. HCs have been used in supermarkets, dairies, institutes, and hospitals. Air Conditioning: A large Italian manufacturer is marketing propane cooled portable air conditioners since 1995, and has now expanded the HC product range to split system air conditioners for office and domestic use. A/C using HCs are also operating reliably in universities, hospitals, and public institutions. Mobile Air Conditioning (MAC): In Australia, over 300,000 vehicles are cooled with hydrocarbons in the air conditioning system. A similar figure can be found for the USA, where HCs are refilled by drivers to existing HFC-based MAC systems, yet without regulatory approval.