Ahmad Addo

Technical and Socioeconomic Potential of Biogas from Cassava Waste in Ghana

This study analyses technical potential and ex ante socioeconomic impacts of biogas production using cassava waste from agroprocessing plants. An analysis was performed for two biodigesters in two cassava processing communities in Ghana. The results showed that the two communities generate an excess of 4,500 tonnes of cassava peels per year. Using approximately 5% of the peels generated and livestock manure as inoculum can generate approximately 75,000 m3 of gas with an estimated 60% methane content from two separate plants of capacities 500 m3 and 300 m3 in the two communities. If used internally as process fuel, the potential gas available could replace over 300 tonnes of firewood per year for cassava processing. The displacement of firewood with gas could have environmental, economic, and social benefits in creating sustainable development. With a 10 percent discount rate, an assumed 20-year biodigester will have a Net Present Value of approximately US

Domestic energy demand assessment of coastline rural communities with solar electrification

148,000, 7-year Payback Period, and an Internal Rate of Return of 18.7%. The project will create 10 full-time unskilled labour positions during the investment year and 4 positions during operation years.

Decision support system for designing sustainable multi-stakeholder networks of grain storage facilities in developing countries

ABSTRACT The coastline rural communities in the Niger Delta region of Nigeria have long suffered from the consequences of poor rural electrification, environmental degradation, and health challenges. There is an urgent need to provide an optimal sustainable and environment-friendly energy system for the coastline rural communities in Nigeria, which has the potential of ameliorating the climate change in this country. The HOMER hybrid optimization software and the estimated domestic energy demand of the coastline rural communities were used to determine the best PV solar energy system. The NASA SEE database with monthly averaged values for global horizontal radiation over a 22-year period was considered in the current analysis. The daily energy demand of a typical household in the communities was estimated for the existing energy demand (EED), future electric energy demand (FEED), and future base energy demand (FBED) scenarios as 5.640, 8.830, and 7.233 kWh, respectively. The suggested best energy system has a cost of electricity of 0.651, 0.653, and 0.674

Assessment of rice farmers’ knowledge and perception of harvest and postharvest losses in Ghana

/kWh for the EED, FEED, and FBED, respectively. The best energy system gives the best components with an appropriate operating strategy to provide an efficient, reliable, cost-effective, and environment-friendly system. It is shown that both positive energy policies of the Federal Government of Nigeria toward renewable energy penetration and the support from the oil-producing companies toward their operational areas would see the cost of electricity being significantly reduced. It is envisaged that the implementation of the suggested energy system with other environmentally responsible interventions would support the Niger-Delta’s coastline rural communities, whose livelihoods have been impaired by gas and oil exploration, to attain their full environmental and socioeconomic potentials.

Dynamics of inhibition patterns during fermentation processes-Zea Mays and Sorghum Bicolor case study

Abstract Governments in developing countries often face the daunting task of designing a network of grain storage facilities to simultaneously benefit the various stakeholders (farmers, market traders, exporters, etc.) in the grain supply chain irrespective of the conflicting objectives of these stakeholders. Existing decision support systems either require data that are unavailable in most developing countries or have objectives irrelevant in the context of developing countries. This paper therefore develops a decision support system that integrates transportation, pseudo p-median, forecasting and goal programming models to optimally design networks of grain storage facilities to reduce the transportation cost of respective stakeholders. The effectiveness of the proposed decision support system has been demonstrated by comparing phantom networks developed with the decision support system to the Government of Ghana’s network of 48 grain storage facilities.

Some moisture dependent thermal properties of Cashew kernel ('Anarcardium occidentale' L.)

Abstract Farmers’ knowledge and perception of harvest and postharvest losses in rice production across three agro-ecological zones of Ghana were examined using farm-level data collected from 108 randomly selected rice farmers. To examine the perception and knowledge of farmers on harvest and postharvest losses, means of a 5-point Likert scale were estimated compared with the values of the individual perception statements. Results indicated that rice production was male-dominated (80%) with an ageing farmer population (42 years on average), smaller farm sizes (~5 acres) with over 70% of farmers formally educated. This suggests the potential and need for mechanised interventions in rice production. Majority of the farmers sampled (over 95%) had experienced and were aware of harvest and postharvest losses in rice. Whereas over 50% of the farmers were cultivating the Jasmine rice variety, it was perceived by over 65% of the farmers to be associated with higher harvesting losses. Mechanical agents such as lack of appropriate harvesting machinery were perceived by over 40% of the farmers to cause harvesting losses. On the method of rice threshing, over 50% of the farmers used combines, 36% used the threshing by impact “bambam” method, 11% bag beating and 2% used mechanical threshers. Rice harvest and postharvest activities constituted 21% of total production cost, while accounting for nearly 20% of total grain loss. It is recommended that aside the mechanised interventions, efforts should be geared towards proper development of rice fields to ensure sustainable production and improved land productivity.

Water Absorption Characteristics of Obatanpa and Mamaba Maize Hybrids (Zea mays)

Recently ethanol production involved the processing and fermentation of sorghum and maize extracts. Sorghum and maize are cheaper, locally available and a substitute to imported barley malt. Large scale ethanol fermentation systems are usually hampered by instability, in the form of oscillations resulting from ethanol inhibition and the lag response of yeast cells to this inhibition. There is limited information regarding the mathematical nature of such inhibitions in the fermentation of sorghum and maize extracts. In the present work, mathematical models are developed to determine the nature of ethanol inhibition during the fermentation of sorghum and maize extracts. The models were sets of coupled ordinary differential equations based on a Monod type cell growth kinetic model that accounts for product inhibition. The Inhibition patterns considered were; Linear, Sudden Growth Stop and Exponential. The results obtained showed that there is product inhibition during ethanol fermentation using sorghum extracts, with inhibition patterns being Linear and Exponential. However, the results obtained from ethanol fermentation of maize extract also showed that there is product inhibition during ethanol fermentation using maize extracts, with inhibition patterns being Linear and Sudden Growth Stop. The obtained models described with high accuracy, 99% Confidence Interval the dynamics of substrate utilization, product formation and cell growth. These inhibitions which affect the high ethanol yields can be minimized by setting up an optimal control problem using the developed models and solved to determine the control variables that minimize the effect of such inhibitions during the fermentation of sorghum and maize extracts.