The energy demand of Pakistan is increasing rapidly; the country is finally exploring alternatives to expand its power production. Pakistan has to rely largely on fossils for their energy production since electricity generation from biomass is considered. Globally biomass is being used on large scale for energy production as an alternative to fossil fuels. Pakistan is among the world’s top-10 sugarcane producers. So, the potential for generating electricity from bagasse is huge (3000 MW). Currently, there are around 83 sugar mills in Pakistan producing about 3.5 million metric tons of sugar per annum with total crushing capacity 597900 TCD, which can produce approximately 3000 MW during the crop season. Although it seems difficult at that moment, if the government starts to give more attention to sugar industry biomass rather than coal, Pakistan can fulfill its energy needs without negative repercussions or damage to the environment. However, by focusing on growing its alternate energy options such as bagasse-based cogeneration, the country will not only mitigate climate change but also tap the unharnessed energy potential of sugar industry biomass.
Almost all the sugar mills in Pakistan have in-house plants for cogeneration. But the problem is that there are some negative points that must be dealt with properly for effective working of bagasse based power plants. However, due to several reasons, mostly due to financing issues, the sugar mill owners were not able to set up such type of plants. Recently, after financial incentives have been offered and a tariff rate agreed upon between the government and mill owners, these projects are moving ahead. The sugar mill owners are more than willing to supply excess electricity generated from the in-house power plants to the national grid. It would also have saved precious foreign exchange which is spent on imported oil. Renewable energy projects are developed through Carbon Development Mechanism or carbon credit scheme for additional revenue.
Since bagasse is a clean fuel which emits very little carbon emissions it is being financed through the Clean Development Mechanism. High cogeneration power plants are difficult to implement because of higher costs. The payback period for the power plants is unknown which makes the investors reluctant to invest in the high cogeneration project. CDM financing can help improve the rate of return of the project. Bagasse power plants reduce carbon emission in two ways;
- One by replacing electricity produced from fossil fuels.
- Secondly if not used as a fuel, it would be otherwise disposed of in an unsafe manner and the methane emissions present in biomass would pollute the environment far more than CO2
However, some sugar mills are opting to use coal as a secondary fuel because the crushing period of sugarcane lasts only 4 months in Pakistan. The plants would have to be run on coal as the main fuel during the non-crushing season. The CDM effect is reduced with the use of coal. If a high cogeneration plant is using even 80% bagasse and 20% of coal, then the carbon credits are almost nullified. If more than 20% of coal is used, then the CDM potential is completely lost because the emissions are increased. However, some sugar mills are not moving ahead with coal as a secondary fuel because separate tariff rates have to be obtained for electricity generation if coal is being used in the mix which is not easily obtained.
The issue that remains to be addressed is that with such huge amounts of investment in these plants, how to use these plants efficiently during the non-crushing period when bagasse is not available. It seems almost counter-productive to use coal on plants which are supposed to be based on biofuels. The use of coal as a secondary fuel in cogeneration power plant is still debatable.