La biomasse, activité alternative au développement des zones rurales

2- Examples to be followed

The examples of power stations or cogeneration functioning with the biomass are multiple. Many farmers often use biological and renewable fuels in a marginal and artisanal way. Here here some examples of most representative of than one can make on a large scale.

a) The power station of the Mould in Guadeloupe

The renewable sources of energy can constitute, in certain areas isolated like the islands, the only source of comfort. In Guadeloupe, the principal agricultural activity is the culture of the cane with sugar. Bagasse is the residue of the process of the cane with sugar, it is thus the fiber which remains after extraction of sugar. Of a ton of cane, there remains thus 320 kg of bagasse. Bagasse has a heating capacity higher than that of many lignites exploited in the world. Ten tons of bagasse equivalent to almost two tons of heavy fuel with the less polluting and renewable advantage of being over an annual cycle.

Bagasse was already used by the traditional sugar industry in the boiler rooms to produce vapor and even sometimes of electricity, but for its exclusive use. The application of modern techniques makes it possible to release from large surpluses of electricity on the needs for subsistence farming. (Appendix 20)

Bagasse is not available all the year and the production of vapor starting from bagasse coincides by definition with the sugar cycle. Produced energy is very definitely higher than the need for the sugar refineries and it must availability of the Inhabitants of Guadeloupe. Consequently, this production must form part of the continuous total offer of energy suggested by EDF (Electricity of France). It is not thinkable to stop the other power stations the time of the sugar season to give them once on the way the last season. It is thus necessary to offer an about constant production of electrical current. It is however impossible to store bagasse more than one week. Sugars which it still contains, even with low dose after their extraction, cause a fermentation which would make it unusable for a good combustion.

The construction of a power station firstly using the residue of cane with sugar, bagasse, constitutes an essential element of « governmental programme of consolidation and development of the culture of the cane in Guadeloupe »^35(*). The culture of the cane covers 13.000 hectares, that is to say 43% of the arable lands. The collection lasts four months. It produces 500.000 tons of cane normally, this plan was worked out to give again oxygen with this activity which tended to decline : 310.000 tons, only, were produced at the time of the preceding countryside this initiative.

The power station plays a decisive part in the adopted device. The sugar refinery of Gardel concentrates from now on the treatment of all the canes of the Island. Without the contribution of the power station, it would have been necessary to invest in a new boiler room. According to first indications', the sugar production would have found its usual level right now.

In addition, the output of the installation increased considerably. If one compares the whole of the die proposed by SIDEC^36(*) with the traditional sugar refineries using bio-combustion in subsistence farming, the surplus is of 54mW for 100.000 tons of sugar. The power stations of cogeneration can reach an energetic efficiency of surroundings 89% against hardly more than 40% for a power station running with fuel or coal.

* ³⁵ document Internet, http://www.ademe.fr/guadeloupe/Bagcharb.htm, consulted the 06.03.01

* ³⁶ world leader of technology bagasse-coal and specialist in the cogeneration in industry.