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M. T. Sall et al.
three harvests in 24 months. After two years, the dry matter yields obtained with the
two cropping systems (8-month or 12-month cycles) are very similar (Chopart et al.
2015).
Even if it is unlikely that this approach can be adopted directly by the CSS, it
demonstrates a model for cane harvesting outside the sugar cane harvesting period.
This would allow the power plant to be supplied with renewable energy produced onsite (bagasse and then a high-fiber cane) almost all year round, with a very significant
reduction in the use of fossil fuel and no net impact on the annual water consumption
of the crop and therefore on IWRM. In this scenario, water from the Senegal River
would be used to produce electricity for the needs of inhabitants (including food
cooking) by optimizing existing industrial equipment (Water-Energy-Food nexus).
It has also been shown that this fibrous sugar cane is not very sensitive to the
stemborer moth Diatraea saccharalis (Chopart et al. 2015), that it is possible to
reduce fertilization and herbicides compared to conventional sugar cane and that
these canes can be mechanically cut with the same equipment as sugar cane (Chopart,
personal communication, Goebel et al. 2016). They are also more drought-tolerant
(Fig. 9), which could be an advantage if used by small producers who may have
limited or irregular irrigation water availability. Studies have focused on organic
matter management in fibrous cane cultivation systems for biomass, showing that it is
possible to maintain the organic matter stock in these systems (Sierra et al. 2016). The
fact that fiber canes produce more roots (Chopart and Sergent 2015) contributes to the
maintenance of organic soil stock despite higher above-ground biomass withdrawals
than in conventional green sugar cane systems without pre-harvest burning.
Finally, it has been shown that the low heating value of dry above-ground biomass
(LHVd, MJ/kg) is the same in each part of the fiber cane (stems, leaves, green,
dry leaves), about 16.65 MJ/kg. A tight linear relationship between the LHVd and
its energy yield (MJ/m
2 ), regardless of cultivar, age and environment, was found.
Sugar cane energy content assessment could thus be simplified by measuring the dry
above-ground biomass (DAB, kg/m
2 ) and its water content (percentage).
Using results described from the Guadeloupe study on this concept of biomass
cane dedicated to energy production, it would be possible to produce more than 70
tons/ha/year of total dry matter (stems and leaves) with simplified and economical
cultivation practices that reduce consumption of fertilizer and herbicide compared
to conventional sugar cane for sugar production. It has been shown that, unlike
sugar production, it is possible to harvest fiber cane after eight- to fourteen-month
cropping cycles. Compared to conventional sugar cane, this would allow planting
and harvesting dates to be spread over a larger part of the year and thus enable more
efficient irrigation management.
The Guadeloupe findings could potentially be adapted for the environmental and
technical conditions of the CSS with few modifications. Research on fibrous cane
varieties dedicated to energy or for multiple purposes is, or has been, undertaken in
some other countries, such as the southern USA (Sandhu 2018), Brazil and the West
Indies (Matsuoka et al. 2014).
M. T. Sall et al.
three harvests in 24 months. After two years, the dry matter yields obtained with the
two cropping systems (8-month or 12-month cycles) are very similar (Chopart et al.
2015).
Even if it is unlikely that this approach can be adopted directly by the CSS, it
demonstrates a model for cane harvesting outside the sugar cane harvesting period.
This would allow the power plant to be supplied with renewable energy produced onsite (bagasse and then a high-fiber cane) almost all year round, with a very significant
reduction in the use of fossil fuel and no net impact on the annual water consumption
of the crop and therefore on IWRM. In this scenario, water from the Senegal River
would be used to produce electricity for the needs of inhabitants (including food
cooking) by optimizing existing industrial equipment (Water-Energy-Food nexus).
It has also been shown that this fibrous sugar cane is not very sensitive to the
stemborer moth Diatraea saccharalis (Chopart et al. 2015), that it is possible to
reduce fertilization and herbicides compared to conventional sugar cane and that
these canes can be mechanically cut with the same equipment as sugar cane (Chopart,
personal communication, Goebel et al. 2016). They are also more drought-tolerant
(Fig. 9), which could be an advantage if used by small producers who may have
limited or irregular irrigation water availability. Studies have focused on organic
matter management in fibrous cane cultivation systems for biomass, showing that it is
possible to maintain the organic matter stock in these systems (Sierra et al. 2016). The
fact that fiber canes produce more roots (Chopart and Sergent 2015) contributes to the
maintenance of organic soil stock despite higher above-ground biomass withdrawals
than in conventional green sugar cane systems without pre-harvest burning.
Finally, it has been shown that the low heating value of dry above-ground biomass
(LHVd, MJ/kg) is the same in each part of the fiber cane (stems, leaves, green,
dry leaves), about 16.65 MJ/kg. A tight linear relationship between the LHVd and
its energy yield (MJ/m
2 ), regardless of cultivar, age and environment, was found.
Sugar cane energy content assessment could thus be simplified by measuring the dry
above-ground biomass (DAB, kg/m
2 ) and its water content (percentage).
Using results described from the Guadeloupe study on this concept of biomass
cane dedicated to energy production, it would be possible to produce more than 70
tons/ha/year of total dry matter (stems and leaves) with simplified and economical
cultivation practices that reduce consumption of fertilizer and herbicide compared
to conventional sugar cane for sugar production. It has been shown that, unlike
sugar production, it is possible to harvest fiber cane after eight- to fourteen-month
cropping cycles. Compared to conventional sugar cane, this would allow planting
and harvesting dates to be spread over a larger part of the year and thus enable more
efficient irrigation management.
The Guadeloupe findings could potentially be adapted for the environmental and
technical conditions of the CSS with few modifications. Research on fibrous cane
varieties dedicated to energy or for multiple purposes is, or has been, undertaken in
some other countries, such as the southern USA (Sandhu 2018), Brazil and the West
Indies (Matsuoka et al. 2014).