Chemical Refrigerants – What are their real climate impacts?
Introduction – What does Greenpeace say?
The steady growth in extreme weather events around the world signals that human-induced climate change is happening right now. We have witnessed unparalleled devastation around the world from record floods, fires, droughts, more frequent and intense tornadoes and hurricanes. In some countries, millions of acres of agricultural land have been lost due to flooding, while other countries report massive declines in crop harvests due to heat and drought.
In 2009, NASA’s eminent climate scientist, Dr James Hansen, warned that the “climate is nearing the dangerous tipping point.” A ‘tipping point’ in the climate system implies abrupt, non-linear, unforeseen and unpredictable changes. It is reaching thresholds of no return, where human intervention has little or no capacity to restore nature’s balance.
Measuring the global warming potential of Chemical Refrigerants. (HFCs)
Global warming potential (GWP) measures the potency of a greenhouse gas over a specific period of time, relative to carbon dioxide (CO2), which has a GWP of 1. An important aspect of GWP is the timescale used: there are 20-year, 100-year and 500-year GWP values for the majority of chemical refrigerants.
At present chemical refrigerants are marketed using their 100 year GWP values. A prime example is that refrigerant R32 is marketed with a GWP of 675 over 100 years. Whereas, the GWP of R32 over 20 years is 2,330.
Refrigerant R404a (which is used in most commercial refrigeration systems) is marketed using a GWP of 3922 over 100 years. The GWP of R404a over 20 years is 6,010.
Refrigerant R410a (which is used in most air conditioning systems in Australia) is marketed using a GWP of 2088 over 100 years. The GWP of R410a over 20 years is 4,340.
Chemical Refrigerants are Super Greenhouse Gases.
The vast majority of Chemical Refrigerants (HFCs) are super greenhouse gases with very high global warming potential. By way of another example, HFC-134a, the most widely used HFC, has 1,430 times greater global warming potential than CO2 (on a 100 year time span). The global warming potential of HFC-134a, on a 20-year time span, is 3,830 times greater than that of CO2.
The Average Lifetime of Chemical Refrigerants.
Greenpeace say that the average lifetime of the chemical refrigerants (HFCs) in use today is 21.7 years and therefore better suited to the 20-year GWP metric. Their short-term climate impact is thus diluted when measured using GWP100 and not adequately accounted for in climate policies. The GWP20 metric better reflects the true potency of HFCs during their actual time in the atmosphere. Indeed, the average GWP20 for HFCs (at 4,582) is 94% greater than the GWP100 average (at 2,362.)
As a result, the short-term ramifications of high-level HFC consumption are far greater when their global warming contribution is measured according to their 20-year GWPs (20 GWP), instead of their 100-year GWPs (100 GWP), the current reference point.
We must all act now.
We must act now to ensure that overall greenhouse gas emissions peak no later than 2015, decline rapidly thereafter, and reach as close to zero as soon as possible. We must think both long and short term, and take immediate measures that will have significant climate benefits over the next several decades.
What can we do as individuals to help?
Natural Refrigerants such as ammonia, carbon dioxide and hydrocarbons are already available and technically and economically feasible. These refrigerants have GWPs of less than 3 over 20 years. There is no need for the continued use of HFCs or HFOs. There is no need for any new chemicals. We need a long-term approach that prioritises the real solutions. Mr Klaus Toepfer from the United Nations Environment Program said in March 2004, “Fighting Climate Change requires Governments, Businesses and Citizens across the Globe to harness new technologies in the pipeline and act”. When it comes to HFCs, all you need to do to become a climate activist is make smart consumer choices. Choose an air conditioning or refrigeration system that uses a natural refrigerant.
Summary
Greenpeace say that the chemical industry is blocking real solutions while harming the climate. Since the Montreal Protocol was signed, the chemical industry has introduced a series of unnecessary chemicals harmful to both the ozone layer and the climate.
Governments in both industrialised and developing countries must set progressive restrictions on the use of HFCs, with an aim to their eventual phase-out. The GWP20 index provides policy makers with a more accurate measure of the effect of climate action versus HFCs over the next few decades. It should provide even greater incentive for governments to enact measures that progressively limit and phase out the use these potent greenhouse gases.