Cogeneration Facts

Matthews Bantsijang

• Cogeneration: Simultaneous production of electricity and process heat from a single dynamic plant.  

• Largely produced from sugarcane bagasse by product. 

• A number of countries in the Africa region have successfully deployed cogeneration e.g. Mauritius, South Africa, Kenya, Swaziland, Malawi and Uganda.  

• Attractive potential for scale-up as most sugar factories already practice cogeneration using low pressure systems – require modest investment to generate excess power

Biomass Cogeneration – Status and Trends

Cogeneration in Mauritius - Lessons for Africa

• Successful in sale of power to the grid
• Accounts for close to 40% of a 725MW national generation capacity (of which 25% bagasse)
• Began with smaller installations (1.5MW - 5MW, now installing 70MW plants)

Others 

Sugar Industry 

Cogeneration potential in the sugar industry in selected African countries

• Feed-in-tariff (or price paid to cogenerators by utilities) not pre-determined and often set too low,

• Negotiations of power purchase agreement (PPA) can be too lengthy (took over 10 years to negotiate cogeneration PPA in Uganda),  

• Two key policy measures:
• Pre-defined Feed in tariff
• Standard PPA.

Biomass Cogeneration 
Key Challenges 

Bio-ethanol – Key Challenges 

• Need predetermined price for bio-ethanol
• Compulsory requirement for blending
• Key policy measures
• Set attractive price for bio-ethanol
• Establish requirement for blending

• Protection and ring-fence away influence of fossil oil companies

Biogas - Challenges 

Source:The Republic of Uganda, 2007 

• Substantial water requirements of biogas under-estimated. 

• High-up front costs that require credit system – principal reason for better performance at institutional level. 

• For small scale systems, important to limit scope of initial dissemination efforts to minimize maintenance cost.

Bio-diesel - Challenges 

• Well proven at small scale but jury still out on large scale trials being initiated in various countries. 

• At large scale, requires significant applied R&D to establishment of new agricultural system.  

• High costs associated with technology transfer & adaptation. 

• Possible competition for land between biodiesel feedstock and food crops but can grow in relatively arid areas where access to land is probably less contentious. 

• Local financiers still uncertain due to unfamiliarity with this option.  

Gasification - Barriers 

• Limited technical expertise on biomass gasification in the region.  

• High risk perception from potential project implementers and financiers due to unfamiliarity with option. 

• Need to increase awareness, enhance skills and initiate additional pilot test plants.

Key Sustainability Issues 

(www.afrepren.org & www.unido.org)

• Equity: Will the poor benefit?
• Revenue sharing mechanism.
• Case of West Kenya sugar factory where cane farmers get 51% of ex-factory sugar price, 

• Meet energy needs of the poor?
• Primarily through increased incomes subject to existence of adequate revenue sharing mechanism.
• Modern biofuels cleaner with lower indoor emissions but cost still an issue. 

• Is there sufficient land?
• Most land requirement projections for meeting internal biofuel demand in the near term appear to be manageable.
• Less certain if one takes account of biofuel export markets – need additional assessments.

Key Sustainability Issues 

• Adversely affect food security?
• Experience in sugar growing areas indicate increased food security as a result of increased incomes – subject to regular payments for sugar cane delivery and adequate revenue sharing mechanism. 

• Biodiversity and natural resource management
• Biofuels development tends to lead to mono-crop culture and intensive use of fertilzier and pesticides.

Needs additional detailed assessments. 

Priority Options 

• Wetlands (Moist and rainland areas)
• Short Term Options
• Bioethanol
• Cogeneration
• Medium to Long Term options
• Biodiesel
• Biogas
• Biomass Gasification 

Way Forward 

• Short Term  

• Focus on proven options that build on existing agro-industries that use available agro-wastes (such as bioethanol in existing sugar industries) to minimize start-up costs and reduce risk. 
• Undertake regularly updated detailed resource assessments. 
• Set pre-determined prices for bioenergy options. 

• Establish supportive regulatory and policy measures such as standard PPAs and blending requirements. 

• Concentrate on investment analysis and preparation of “bankable” investment proposals. 

• Encourage national, regional and international exchange of experience, skills and technologies (regional bioenergy network).  

·        Medium to Long Term

o       Finance resource assessments  

• Support R&D and local adaptation  

• Initiate pilot and demonstration investments  

• Strengthen national, regional and global technical exchange of skills, experience and information.