Using HFCs responsibly implies a number of actions, aiming at reducing at the utmost their emissions and any negative impact on the environment. This criterion is increasingly taken into account during the design, installation, servicing and disposal of HFC-using equipment. To make it work, there is also an ongoing need for informing and training of all stakeholders involved with Fluorocarbons.
HFCs have a global warming potential if released, hydrocarbons are flammable, ammonia is toxic if released and carbon dioxide (CO2) operates at considerably higher pressure. For refrigeration and air-conditioning systems, using any of these refrigerants, to operate effectively, safely and efficiently, emissions must be minimised.
Globally, HFCs are considered by many as the most appropriate choice of refrigerant based on their overall technical performance, environmental impact and safety, in the vast majority of applications. As greenhouse gases the need for their responsible use has long been recognized.
Containment has been shown to work. Systems such as the STEK in the Netherlands clearly demonstrate that containment does work. “From leakage rates at the level of 30% at the early 90’s, emissions in the Netherlands now are at the average level of 4.8%, with 92% of installations having no emissions at all in the reference year 1999.”
This result is corroborated by a German study, quoting mean refrigerant leaks of 4.1% annually – and even 2.3% annually when discarding the case when an accident caused a huge loss of the refrigerant charge.
Worth to mention is the fact that 15% of leaks are responsible for 85% of refrigerant loss.
While recognizing their exceptional properties (safety, efficiency, non-corrosiveness and technical ease) the fact remains that HFCs emissions should be avoided. With the quality of the material now available for new air conditioning and refrigeration systems the containment of HFCs is possible
One of the key factors in containment measures is to survey and control all leakage sources.
A number of recommendations have been made, from fittings details to the choice of appropriate valves to the use of more hermetic systems, and of course effective leak detectors.
Of course, leaks can also be avoided by the elimination of accidents (of human as well as material origin), which requires continuous training.
Many of these recommendations are well known and if they are consistently adhered to, it is to be expected that more than 80 % of the identified refrigerant losses could be avoided.
It makes environmental and economic sense to recover and recycle HFC refrigerants, during servicing and at the end of an equipment service life. Since they are safe substances to handle, it is straightforward to remove HFCs from installed air-conditioning systems for maintenance or at end- of- life. Recovery equipment is widely available and the deliberate release of refrigerant is banned in most countries. In addition the proposed WEEE Directive will require recovery or destruction of HFCs when air-conditioning equipment is scrapped. For mobile air-conditioning systems, recovery and recycling at garages is straightforward for HFC 134a. The end-of-life vehicle directive requires recovery of HFCs when the vehicle is scrapped.
In the case of refrigeration or air-conditioning equipment, the fluid in the system can be drained out and reprocessed for re-use . Recovery of the insulating gas in plastic foam insulation is more difficult but technically possible and, again, the gas may be re-used. The quality of the processed materials must be equivalent to the quality of virgin fluids. In practice this means that the fluids will be cleaned for traces of lubricants, other solid contamination and humidity.
Recovery and recycling clearly fit within the concept of sustainability. The use of fluids that can be safely and conveniently removed and re-used represents the most sustainable option.
HFCs are intrinsically safe. They are, effectively, non-toxic. Most are not flammable and those that do burn have a narrow range of "combustion limits". This means that they can be made inert with non-combustible gases relatively easily. As a result, HFCs may be recovered from used equipment simply and without significant danger.
Other refrigerants, such as hydrocarbons, have much wider combustion limits and it is not practically possible to render them safe by "inerting" with non-combustible gas. This leaves destruction as the only viable end-of-life option.
If ultimately the fluids cannot be recovered nor recycled, the best practice is to send them to some of various proven destruction processes, so that they will not be released to the atmosphere.
When designing a system foreseen to make use of fluorinated gases, responsible practices can deliver substantial reduction in energy consumption, and in the Fluorocarbons charge size.
Reducing the internal volume of system components will allow reducing the total charge of refrigerant, while ensuring no negative effect on energy efficiency.
Replacing traditional heat exchangers with compact heat exchangers can further on reduce the refrigerant charge.
In supermarkets refrigeration, the location of the machine room closer to the display cabinets, the use of distributed systems instead of centralized systems, the design of the store itself, can all influence the volume of fluid required for functioning, and the probability of leakages and emissions.
For new buildings, it is useful to take into account the climate conditions by the use of heat absorbing glazing, choosing its amount, orientation and thermal performance. For the building itself, insulation should be optimized for both heating and cooling seasons, reducing the heat load in the winter, the air conditioning power consumption in the summer.
Leakage and bad practices are the major source of Fluorinated Gas emissions. One way of overcoming this is to ensure that only competent people handle these products – as well as other refrigerants including flammable and high pressure fluids.
It is also desirable that end users of refrigeration equipment are requesting that companies servicing and supplying equipment provide evidence of their personnel's competence.
Some countries (for example The Netherlands through STEK*) have already implemented a mandatory training scheme for people dealing with all kinds of Fluorinated refrigerants. With the help of the EU Leonardo programme, AREA (European Federation of Air-conditioning and Refrigeration Contractors) has developed an elaborate skills set template that will assist setting up appropriate curriculae for vocational training.
The future F-Gas Regulation will also require Member States to establish programmes to provide for the training and certification of personnel involved in making inspections for leakage, and for those involved in the recovery, recycling, reclamation and destruction of fluorinated gases.
Such training programme would address the handling, the transport and the storage of refrigerants, aiming at preventing and detecting leakages and emissions through regular inspections, defined procedures, etc.
It is understood that such a scheme could also be a basis for the monitoring of the use and emission of Fluorinated Gases, as required under EU Regulation and the UNFCCC.