The Impact Of Refrigerant On the Environment
At the beginning of the 1930s it was believed that the perfect refrigerant had been discovered - different CFC components. Later research demonstrated that CFC (for example R12) severely affects our environment.
Due to this, a less aggressive refrigerant has been developed - different HFC compounds (for example R134a). In addition there are now a number of international agreements, national legislation and directives that govern the use of refrigerants.
Initially CFC compounds were called Freons. But Freon is in fact only the name of a product from a manufacturer.
Later there was international agreement about a R code for refrigerants. The letter R is for refrigerant and the number that follows it indicates the chemical compound.
The effect of refrigerants on the environment is usually listed in ODP and GWP.
ODP = Ozone Depleting Potential.
GWP = Global Warming Potential.
| Type | Refrigerant | ODP | GWP |
|---|---|---|---|
| CFC | R11 | 1 | 1 |
| CFC | R12 | 0.9 - 1.0 | 2.8 - 3.4 |
| HCF | R134 | 0 | 0.23 - 0.29 |
The ozone layer around the earth
Sunlight contains a lot of energy rich short wave radiation (ultraviolet radiation) which is damaging to all living cells. The ozone layer in the stratosphere, 15-40 km (9-25 miles) above the earth, catches almost 99% of the dangerous ultraviolet radiation.
The ozone molecule is unstable and consists of three oxygen atoms (O3). Ozone is consumed and renewed constantly, it is regenerated by sunlight.
Human emission of chlorine etc (which is in R12) breaks down the ozone layer quicker than it can regenerate. This leads to what are called holes in the ozone layer, which are in reality areas where the ozone layer is thinner.
Thinner ozone layers result in increased ultraviolet radiation which causes greater damage to all living cells, both animal and plant.
Some examples of this are:
- increased incidence of different forms of skin cancer.
- increased incidence of eye damage (for example cataracts and what is known as snow blindness).
- damaged vegetation (amongst other things worsened growth/harvests).
- damage to marine life (for example killing of algae, poorer quality vegetation and fish).
Greenhouse Effect
Sunlight which is a short-wave energy rich form of radiation reaches the earth. Most of the sunlight is reflected towards the earth and bounced back to space as longwave heat radiation. Some of this heat radiation is reflected back towards the earth by gases (= greenhouse gases) in the atmosphere. This phenomenon is usually known as the greenhouse effect.
The greenhouse has existed since the atmosphere was created and it this gives us a tolerable temperature on the earth. Without the greenhouse effect the average temperature of the earth would be approximately -18°C (0°F) instead of the present approximately 15°C (59°F).
The human way of life, in particular during the last 30 years, has considerably increased the emission of greenhouse gases into the atmosphere (for example carbon dioxide, methane, NOx, CFC).
This results in the gas layer in the atmosphere becoming thicker - and therefore more heat is reflected back to the earth, causing the average temperature of the earth to rise. In other words, the greenhouse effect is increased.
The consequences of an increased greenhouse effect are a subject of much discussion, but without doubt it damages the climate balance of the earth.