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Greenhouse effect and bioenergy

It is really frequent to speak about greenhouse effect nowadays, as this phenomenon can have some terrible consequences. So, it is important to know why it exists and how it can be avoided. Some solutions exist but are still difficult to apply at a large scale...

Nowadays, everybody speaks about greenhouse effect as a terrible thing which is dangerous for mankind. It is true that its effects must be fought, in order to be sure that future generations will not be in danger, but the problem is that we are all responsible of this, and concerned too.

Greenhouse effect is natural and necessary

However, since the Earth is born, this phenomenon has always existed, and it is necessary for life. In fact, without this, the average temperature on our planet would be too cold : -20°C whereas it is +15°C today (cf www.lesamisdelaterre.org/publications/publications_4.html). So, life would not have existed without this, and therefore some gases are useful.

Indeed, gases like CO2 are present in atmosphere, and they have the same effect as a window. In fact, the warmth which comes from the Sun is reflected at the surface of the Earth, in the form of infra-red, and the gases in the atmosphere capture a part of this heat, and keep it all around the planet.

Besides, our planet has not always had the same temperature. For billions of years, periods of heat and freezing have followed each other, and there are always variations of the average temperature, if we look during a long time. (cf. www.notre-planete.info/). The following graph shows these variations, for 20000 years. The blue line represents the average temperature, which is 15°C.


This document is evidence that temperature always changes, but it is worrying too, because we can see that it will grow rapidly in the next 100 years, and will be higher than the average. This growth will be one of the most important that Earth has never known, and temperature will greatly be superior to 15°C. Therefore we can say that it is not only a natural phenomenon.

Mankind must fight what it has accelerated

For two centuries, mankind’s activity has grown rapidly, with the industrial revolutions, and it is used to using some energies. These energies have been useful for developing different countries, but, in the other hand, these have been very polluting and dangerous. Petroleum, charcoal, for example, are causes of what happens nowadays, because those reject some harmful gases. And industrial plants used this kind of fossil energies to be productive, without thinking of the environment.

So, even if greenhouse effect has always been there, mankind has accelerated it, and it continues. Activity and production have always been priorities for us, but, now, we are getting conscious of the environmental problem, but it may be too late...

Now, science has determined what the negative consequences are, and it really is a warning. Thus, we have to react all, in order to repair and fight what we have been doing for 200 years.

Consequences will be catastrophic

We saw that the average temperature will grow, higher to 15°C. If there is no change, it will reach to 18°C at the end of our century (according to the last graph). Even if there have always been changes, it will grow too rapidly, so that consequences would be terrible.

For example, if it gets too warm on our planet, glaciers are about to thaw and vanish. Their fauna is also in danger, like white bears or some fishes, which cannot adapt to warmer water. These glaciers, if they thaw, will make the level of oceans increase, and it could create more and more inundations (in The Netherlands for example, which is a very flat country and threatened by the ocean).

Concerning the climate, periods of dryness and scorching heat will be more frequent, which is unhealthy, especially for old people and babies, who are weaker. These temperatures could also have bad effects on agriculture and crops. In poor countries, where, unfortunately, food is already rare, it will be a serious problem for people’s survival. Moreover, meteorological accidents like hurricanes, twisters... or storms could be part of our life, and we already know their terrible effects. It always causes material damages and human losses.

All this information is detailed in the following website : www.effet-de-serre.gouv.fr/fr/savoir/savoir.htm

With this point of view, it is necessary to make something to change the situation. The matter is that it will not change in one day, thus we must not be selfish. The future generations will suffer more than we do, but we have to make their future life easier. That is why we are obliged to act today and all the days following. Solutions must be found and applied nowadays, in order to limit bad effects for the future.

People do not really care, even if solutions exist

As we know what really accelerates the phenomenon, we can fight these causes to be the most efficient possible. The biggest problem is our consumption of fossil energies (petroleum, charcoal, gas) which are useful for cars, heat in the house, industrial production... Nowadays, we cannot live without energy.

Environmental solutions

On the one hand, the first solution is to find new sources of energy, which are not polluting. And it exists, in the form of wind power, solar or electrical energy... (all kinds of renewable energies are presented in www.ciele.org/filieres/) For example, electrical cars exist to replace oil. With electricity, there are no rejected gases. Besides, it is possible to produce electricity with wind or water, instead of using other polluting methods (nuclear power). Furthermore, bioenergy is really important and useful : it consists in producing energy by using products of biomass (residues of animals or plants, wood...). (cf. www.canren.gc.ca/tech_appl/index_f.asp ?CaId=2&PgId=249)

With this bioenergy, we can produce energies for all kinds of industries only with biomass. This means that there is always a renewal of this material, and it will still be present in the future. Thus it is the better way to assure the “durable development”. For example, if you get heat with wood energy, you have to plant forest to continue the cycle. With this forest which is a carbon well, you can stock some CO2 which has a beneficial result against the greenhouse effect. That is why the role of bioenergy is truly important for the environment (plants stock some carbon to grow)

On the other hand, great meetings exist to speak about this environmental problem (Johannesburg, 2002) and all the very important people attend these meetings. Some protocols may be edited for countries to produce while taking care of the environment. The most famous is Kyoto’s protocol, signed in 1997 by 180 nations (www.ec.gc.ca/climate/kyoto-f.html) in order to respect environmental aspects.

We do not really apply these solutions

The first problem with this is that people do not really want to change their ways of life. They do not really care and are not conscious of the gravity of the situation. They may think that it will not change even if they change. But, if everybody gets conscious, there will be a global effort which could be efficient. Furthermore, concerning cars, people want to move easily, and cars represent freedom, contrary to public transports. And, a petrol car is the most high-performance (we are going to talk about this in the last part of this report.) For example, in France, nobody will replace one’s car by a bike.

The second problem is that even important people do not want to react. The best example that I can give is George W. Bush, the president of the United States. He refused to apply Kyoto’s protocol, only to produce more (cf. www.commondreams.org/headlines02/0215-01.htm). He only sees the economical aspect, without thinking of what it causes. So, it is easy to understand people who do not want to make an effort if the most powerful man of the world does not make anyone. He made a mistake because he must have given the example for the others, but he only thought about money and power of his state.

Solutions are not perfect

If renewable energies are not very present in our way of life, it is due to some defaults. The first one is that it is less productive than fossil energies. For cars, an electrical one is really limited in kilometres, and it is not simple to find a place to recharge batteries. And for production of electricity with wind power, it is less effective than fossil energies, and prices for one Kilowatt-hour are often more expansive. (www.ciele.org/filieres/eolien.htm)

Besides, I think that there are not enough prevention campaigns, concerning the greenhouse effect. If there is no information on it, we cannot be conscious that it is a serious matter, and that we have to change our ways of life right now. Nobody cares of glaciers which are thawing, because in middle Europe, we are far from these regions of the world. But, we do not know that it will consequently increase the level of water, which represents risks of inundations in our lands. So, if we want to apply solutions, we have to explain why it is important to do it, and I think that it misses nowadays.

Concerning bioenergy, I think that it should have favourable consequences if people used it more. However, it is difficult to make them understand that it is possible to replace petroleum by vegetal oil. I believe that people do not trust this kind of energy, because petroleum seems to be so perfect for cars, that, according to them, there is no use to replace it.

Moreover, concerning wood energy, I think there is a big problem of communication. In fact, most of people think of deforestation when one speaks about forest and use of wood. They may believe that producing heat with wood requires cutting a lot of forest and they may do not want to be responsible of deforestation. The problem is that it is mainly false. Even if it may be a reality in South America, forest still grows in our European countries and it is not wood energy which will increase this problem of deforestation. This matter might explain why wood is not largely used to produce energy in houses.


To conclude, we now know what the greenhouse effect is, and what it will generate in the following years. Consequences are so terrible that we have to fight what we have really been increasing for the two last centuries. In fact, solutions like bioenergy exist but it is still difficult to apply it on the life of all days. It is very hard to make people conscious of the problem, therefore more information is necessary. With this, it could be possible to change mentalities, and show that bioenergy is also efficient to produce energy, but with less pollution. If we succeed in replacing fossil energies by bioenergy or renewable energies, it will be a good progress to mitigate the greenhouse effect.

Thibaud SURINI

Links :


www.canren.gc.ca/tech_appl/index_f.asp ?CaId=2&PgId=249







Thibaud Surini

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