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Mauritius Island Nation Chapter j 15 295

an environmentally sustainable way. The low efficiency of current techniques
used for cogeneration indicates that improving the thermal processing of
biomass can reinforce its ability to contribute substantially to the growing
demands for bioenergy. Conventional cogeneration techniques can produce up
to 80 kWh per ton of sugarcane processed, whereas with advanced techniques
the generation can reach 200 kWh per ton of sugarcane processed (Pellegrini
and de Oliveira, 2011). New technologies are needed to enhance the energy
yield from bagasse. Among the options, gasification is one of the most
efficient methods for combined heat and power generation due to its potential
for higher efficiency cycles (Knoef and Ahrenfeldt, 2005). Gasification refers
to the process during which organic or fossil-based carbonaceous materials are
converted into carbon monoxide, hydrogen, methane, and carbon dioxide
(Speight, 2010). To perform this conversion, the materials are reacted at high

temperatures, typically above 1000 C, in the presence of a limited amount of
oxygen and/or steam. According to Riehl et al. (2012), gasification technology
has been developed over the last decades as an additional option for fuel
production, as well as chemical substances, at a more competitive price when
compared with crude-oil-based products. Moreover, the payback period of
6 years for incorporating this technology in cogeneration system appears very
reasonable (Okure et al., 2006). As shown in Table 15.2, bagasse-based
electricity accounted for 510 GWh of the total 2996 GWh electricity
production for Mauritius in 2015. According to one study (Autrey et al., 2006)
electricity production from higher fiber cane could rise to around 4600 GWh
using technologies such as biomass integrated gasification combined cycle.
This corresponds to approximately a 10-fold increase in present electricity
generation from bagasse and exceeds the current total electricity generation by
more than 1.5 times. However, research on making gasification-based power
generation commercially viable is ongoing (Asadullah, 2014).
Mauritius has recently begun to tap the potential of landfill gas, primarily
composed of methane, to produce electricity. Mauritius is currently disposing
about 420,000 tons of solid waste at the unique landfill of the island, situated
in the village of Mare Chicose. A landfill gas to energy plant of 3.3 MW
capacity has started operation in November 2011 and generates nearly
22 GWh of electricity annually (Sotravic, 2012). The plant is expected
to reduce 668,000 tons in GHG emissions throughout its first 5 years of
operation, representing about 12% of the island’s annual GHG emissions
(CAIT, 2015). A study evaluated the present maximum annual energy
production capacity of the landfill to be 50.50 GWh (Surroop and Mohee,
2011). Although only 15%e25% of the total gas yield is presently being
collected, much higher landfill gas recovery rates in excess of 50% are possible
with efficiency gains. The plant will be equipped by mechanisms to enhance
the landfill gas collection mechanism by the end of 2016 (Karagiannidis, 2012).
These very large volumes of untapped landfill gas have the potential to
significantly increase power generation from this source.