Dr. Volkmar Hasse, Program Manager at GTZ (German Technical Cooperation), has been involved in a project to introduce HC room air conditioning to the Chinese market. hydrocarbons21.com talked to him at the UN Montreal Protocol meeting in Geneva about safety concerns and how to effectively eliminate them.
hydrocarbons21.com (HC21): The GTZ is going to help to convince policy makers at the UN level that hydrocarbons are safe or, differently put, how they can be used safely. What would be the way to educating people?
Volkmar Hasse: Safety with hydrocarbons in air conditioning and refrigerators, and any other walks of life where they are used, is mainly a technical problem. Many systems we are using every day are inherently dangerous to use. We know how to make them safe for everyone to use. To ensure that, there are technical standards and guidelines on how to make safe equipment. Hydrocarbons in air conditioners can in the same way be used safely which does not require any special knowledge by the equipment owner. However, these air conditioners are not yet widely available in the market.
HC21: Because they don’t have a proven track record yet?
Hasse: Yes, they do. Let’s put it that way: There are some rumours of terrible accidents. However, we know of no documented cases where such accidents happened due to the fact that the equipment runs on hydrocarbon. The stories always tell about physically rather impossible incidents. Fact is that in many countries R22 air conditioners are simply being re-filled with hydrocarbon refrigerant, a practice which we consider unsafe unless the equipment is properly retrofitted by a trained refrigeration engineer. Still, hydrocarbon air conditioners designed for and produced containing hydrocarbons are not yet widely available.
HC21: How many are there on the global market?
Hasse: There are a good number of small units already produced by New Zealander and Italian companies. One model even won an energy efficiency prize here in Switzerland. There are also different applications. We know that hydrocarbons are even used in automotive air conditioners in the range of many hundred thousands in the world. Here, they have a rather good track record despite the fact that there are no technical precautions against a large quantity of the gas entering the small passenger cabin. This is an application not very well regarded by the car industry. I think it would be necessary to have a well regulated market and technical standards for the safe use in mobile air conditioning.
HC21: Regarding the product you are showcasing here and for which Gree has provided the designs, how have you dealt with the aspects to ensure that it is safe?
Hasse: The requirement for the design was to comply with the European norm EN 378. The Chinese, at this moment in time, do not have a suitable industry standard for safe use of hydrocarbons in air conditioners. So we had to use an existing standard and we chose the European norm, which some say is overly cautious, to make the system inherently safe. The idea was to make it so safe that at the point of sale the reference to hydrocarbons is not needed. The consumer buying the product doesn’t have to be told that hydrocarbons are inside. It is quite the same like buying a refrigerator in Europe. Most of them contain hydrocarbons today. You buy it because it is a “green” product, and on top of that it saves you electricity. That is the all the customer will ever know about the fact that the product contains hydrocarbons. The same can be done with air conditioners where the only difference is that they contain a higher refrigerant charge. So, again, the question if safety can be ensured can be answered with “yes”.
HC21: The customers will come both from China and the EU?
Hasse: Our intention is to help China to introduce this technology in the domestic market, in the light of the 2013 Montreal Protocol freeze of HCFCs. The market for the current R22 air conditioners is still expanding rapidly and we need to do something to head off this growth, so that at the end of 2012 there will be no further increase. The design of this particular product is meant to help the Chinese to have an alternative on the market that would fulfil the requirements of the Montreal Protocol. Since China has not yet developed an appropriate industry standard – it is currently working to draft one – Gree would like to wait first with selling its new products on the Chinese market. Instead, and since the product has been made to satisfy the European standard, they are now looking to attract European customers. The production line we are going to install together with Gree will manufacture 180,000 units a year. It will be ready by the end of this year, latest early next year. By then, a market for these 180,000 units will have been found. Interest has been expressed already by German companies that would like to buy this equipment. More importantly, other Chinese manufacturers will also benefit from the knowledge gained in this project and may themselves decide to produce hydrocarbon models of their own.
HC21: From the design point of view what can be done to make the system inherently safe?
Hasse: There are several options, depending on how the manufacturer is going to reach a safety standard. The European standard is regulating the charge amount in relation to the room size to avoid flammable concentrations in case of a rapid leak. The Gree AC unit has a reduced charge size to comply with the European norm. There are also other ways to increase safety. Some are integrated in the system, as electronic leak detection systems that would shut down the system and alert the owner if a leak is detected. This has also an added benefit: it will detect even harmless leaks that would otherwise lead to a reduced performance of the system and would therefore raise the electricity consumption. Since nowadays energy efficiency is very important, this is a very useful feature.
HC21: What do you reply to proponents of HCs talking about hands being blown off at even these small charges of 150 grammes?
Hasse: It simply does not happen. Nobody has any data that would prove these allegations. If these data exist, we would be happy see them and analyse what might have happened. There were the same rumours 10 years ago, saying that when you open a refrigerator containing HC refrigerant it could blow your head off. HC is a flammable refrigerant that, unless it is ignited in a small tight space, does not explode, but burn. Should all refrigerant flow out at once with a source of ignition present, a short flash flame will occur but no explosion, and the fire would not last long enough to propagate to other combustible materials in the room.
HC21: What is the typical refrigerant charge of an AC system?
Hasse: There is any charge possible, just like with other refrigerants, depending on the cooling requirements and considering the respective safety requirements. The machine on display here has a hydrocarbon R290 charge of 265 grams with a capacity of 2.7 KW.
HC21: And this is also far below the charge you would need in a car air conditioning system, where it is typically around 500 grammes?
Hasse: Hydrocarbons in car air conditioners are not currently being discussed by car manufacturers. However, as I mentioned there are several hundred thousand units operating with their old air conditioning systems but with hydrocarbon replacing other refrigerants such as R134a and R12. There are no statistics showing that HCs would have added to the severity of any car accident. Obviously, there have been road accidents with R134a systems and with HC systems, as well. To the best of our knowledge, and that is based on insurance data, the fact that the systems contained HC have not had any more severe consequences than the ones with R134a.
HC21: Going back to the training aspect, how important is that in making sure HC systems are serviced safely?
Hasse: In our opinion, design and training have to go together to make a system using HCs inherently safe. Every technical equipment needs to be serviced once in a while. All new air conditioning technologies, including HC, which are due to replace HCFCs in the near future require some new know-how from service technicians. The countries’ decision makers, hopefully with the assistance of the Montreal Protocol, have to make sure that refrigeration technicians in their country are aware that a new flammable refrigerant has entered the market. This can be done in several effective ways. The know-how required to service this kind of machine is not very complex. It can be passed on anywhere in the world in any language and in simple words. Technicians mainly have to know that a system contains HCs and then take precautions not to operate with open flames or smoke, and other common sense things. The only problem really is ignorance. However, we can educate the industry how to handle these systems professionally.