Documentation > Greenhouse effect > Greenhouse gases and us > Do I emit greenhouse gases through my daily acts ?
The greenhouse effect, it is well known, is the result of the guilty behaviour of industrials, of Americans, of Chinese that should not start to consume oil, but.....not mine for sure !
Alas, we all are, through our everyday actions, direct or indirect emitters of greenhouse gases, either because we directly burn a fossil fuel (oil, coal or gas), what generates CO2 emissions, or because we choose to buy a product, which led to emissions during its production, or because we use a service that requires combustion (for exemple an admission to the swimming pool "includes" the emissions linkeed to the heating of the water). Considering that, as consumers, we do not have the slightest share of responsibility is probably drawing a conclusion a bit quickly !
I would like to suggest below a couple of figures linked to acts that belong to everyday life (or almost). Unless otherwise mentionned, these figures include all greenhouse gases. All these figures have been obtained from the Bilan Carbone (that I could translate as "carbon balance sheet") that I contributed to set up for the french environment agency, ADEME.
To make these figures meaningful, it might be useful to recall that the average emission of a French is 2,2 tonnes carbon equivalent per year, all greenhouse gases taken into acount, the forestry sink also taken into account. But what will be really useful is to compare these figures with what we can emit in order to stabilize the CO2 concentration in the atmosphere....
To heat a house in the winter, one will emit (essentially in CO2) :
with 3,000 liters (800 US gallons roughly) of : 2,4 tonnes carbon equivalent (this figure includes emissions linked to the oil extraction, transport, and refining, and of course the combustion in our boiler) ;
with natural gas, for the same amount of energy given to the boiler, that is 29.780 kWh : 1,9 tonne carbon equivalent (the upstream emissions, linked to extraction and transport of natural gas are also included),
with electricity, for a quantitiy of energy equivalent to what we get with 3.000 liters of fuel oil and an efficiency of the boiler of 80% (that means roughly 24,000 kW of electricity), and supposing we take the average "carbon content" of the electric kWh on the grid :
0,6 tonne carbon equivalent in France (where electricity is 80% nuclear produced and 15% hydro-produced) ;
almost 3,8 tonnes in the UK (30% nuclear, the remainder composed of coal and gas fired power plants),
around 4 tonnes in the USA (20% nuclear, the remainder mostly composed of coal).
more than 5,5 tonnes in Denmark (electricity mostly produced with coal, despite wind turbines....) or in Greece (a lot of coal also).
It is important to precise that in winter, when electric heating is used, and therefore when electric consumption rises, coal fired power plants are used more intensively than in summer (in France) to provide extra power, what raises an interesting methodological problem : what should "inherit" the emissions linked to the increase of coal generated electricity ?
only electric heating, say its opponents,
everybody, say others, because there is not only the consumption linked to heating that rises in winter, and anyway electric heating represents twice the amount of electricity produced by coal power plants, so it is not possible to attribute a "pure coal" value to any heater ! I confess that I am among those that agree with the second conclusion (calculations in french).
If one moves 15,000 km (the average distance covered by french cars is 14.000 km per year), it will lead to the following emissions, depending on the means of transportation used :
in a small subcompact car (like a Twingo or a C3), driving in the country, with no trafic jams (giving 47 miles to the gallon or consuming 5 liters/100 km) : about 0,8 tonne carbon equivalent, including the emissions linked to the production of the car and the oil industry taken into account. Par contre la combustion d'hydrocarbures produit aussi des précurseurs de l'ozone (2.000 fois plus "réchauffant" que le CO2) et des oxydes d'azote non pris en compte dans mes calculs.
in a large car, in urban trafic, with trafic jams (giving 17 miles to the gallon or consuming 14 liters/100 km)) : roughly 2 tonnes carbon equivalent (in addition large cars, at least in France, cover a greater annual distance than small ones : they cover close to 20,000 km).
in train (suburban whose work is 30 km away from home, or 10 return trips from Paris to Marseilles) : only 35 kg carbon equivalent per person in France, without taking into account the manufacturing of the train, which is 20 to 30 times less than alone in a small car. This amount depends on the country, because the proportion of trains that run on electricity and the way to producce electricity vary depending on the country.
Kg carbon equivalent linked to 15,000 km traveled by train depending on the country. Let's recall that alone in a very small car it would be close to 1,000 kg : the train is always better. From Infras, 1998
in plane, short haul (10 return trips from Paris to Marseilles, or roughly 15 return trips from Paris to London) : about 1,2 tonne carbon equivalent per person (all greenhouse gases included) in second class, that is 40 times more than in a French train, and still 4 times more than in an English train. This amount ,even jumps to 2,7 tonnes carbon equivalent in Business Class ! (because one occupies more ground space).
in plane, long haul (one return trip from Paris to New York, or a one-way trip from Europe to Japan) : about 0,9 tonne carbon equivalent per person (all greenhouse gases included) in second class, but 3,15 tonnes in First Class, that is 25 to 80 times more than in a boat (where a passenger generated roughly 40 kg carbon equivalent for the same distance).
It is easy to notice that while travelling by plane a passenger emits as much as he would have travelling alone in a car over the same distance. A 747 over Paris-New-York is the equivalent of 450 to 500 small subcompact cars that would travel the same distance.
I also calculated that an airport like Roissy (Paris) is indirectely at the origin of 5 to 10% of all french emissions.
the production of a tonne of wheat generates about 110 kg carbon equivalent, coming for 25% from N2O deriving from nitrogenous fertilizers, and for 75% from CO2 generated by fertilizers and pesticides manufacturing and the direct combustion in the tractor.
producing a tonne of beef carcass (that is just meat with bones, but without skin, entrails, etc) generates roughly 4 tonnes carbon equivalent (more than 10 for veal), coming partly from the methane resulting from enteric fermentation, and partly (and mostly) from the cereal cultures required to feed cattle.
for a ton of poultry (no entrails), 0,5 to 1,5 tonne carbon equivalent depending on the type of animal and the quality.
Basic materials (NB : all these values are european values. I never had the opportunity to work on other figures) :
the production of one tonne of steel generates roughly 0,8 tonne carbon equivalent (from iron ore), of one ton of aluminium roughly 3 tonnes carbon equivalent (from ore also), all greenhouse gases taken into account.
the production of one tonne of plastic generates from 0,5 to 1,6 tonne carbon equivalent depending on the plastic,
the production of one tonne of glass (from sand) generates roughly 0,4 tonne, but 0,12 tonne only if starting from recycled glass,
the production of one tonne of cement generates roughly 0,25 tonne carbon equivalent,
the production of one tonne of wood....sequestrates roughly 0,5 tonne carbon equivalent if it is timber wood produced in europe. Substituting a ton of steel for a ton of wood (for example for a building) allows a saving (a "sink") of more than one tonne carbone equivalent overall if the wood comes from european forests (because new trees must be planted where the old ones where cut in order to make forestry a sink, otherwise it's mere deforestation !).
Transporting goods :
transporting one tonne of goods over 1.000 km in an articulated lorry generates roughly 25 kg carbon equivalent (this figure accounts for the average load factor of trucks in France) ;
a tonne of apples coming from the local producer to the open market in a light truck (25 km) generates roughly 3 kg carbon equivalent,
a tonne of mangoes - or apples - going from South Africa to Europe by plane (let's say 10.000 km) generates 3,2 tonnes carbon equivalent,
a tonne of oranges going from Tunisia to France by plane generates 1,2 tonne carbon equivalent,
a tonne of mail travelling 800 km by night train will generate 2 kg carbon equivalent (in France), while by truck it will go up to 20 kg (for the same distance), and by short haul plane (express delivery, for example) it will soar to 550 kg (10 times more than in train !).
Here as for people, anything that travels by plane leads to emissions way over what it is with the other transportation means, but trucks and even trains are not "climate safe" either !
Of course, all these figures correspond to average values, and are susceptible to vary depending on the circumstances. One might find on this website some considerations on the individual acts that allow a savin on the greenhouse gases emissions.
After consulting these figures, I hope that my reader will accept that it seems difficult to imagine that a massive reduction of the emissions might be achieved by the mere action of some courageous and shrewd political leader, that would just have to do "what is necessary" so that emissions fall, without us having to change anything in our consuming habits....