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Due to a high construction material cost in Ethiopia, it is difficult to afford a shelter by most our peoples. The Hydra form block (HFB) has been identified as low-cost building material with its potential and possibility to reverse the housing problem. Laboratory tests were conducted on Mettu, Nopa, Gore, and Hurumu areas soil. Using hydra form machine with average mold size of 29*14*10cm, hydra form blocks were casted with the three percentages increment of cement. Compressive strength and water absorption tests were conducted at 28 days. The investigation has revealed that all the soil sample except Gore soil have significant characteristics that make it suitable for stabilization with recommended soil properties. From the experimental study, all the blocks except blocks produced with Gore soil have 28th day compressive strength values well above most of the recommended minimum values. Water absorption was less than the maximum limit of 15%. But, for control block and for stabilized with 3% cement, water absorption result is out of the recommended values (0-15) %. The cost comparison of Hydra form blocks with hollow concrete block and fired clay brick shows that the Hydra form block is cheapest walling material in terms of production cost and a typical hydra form block production center can create a job for more than 50 peoples.

Process level integration of solar energy could give an economically feasible solution if the industrial process allows its practical integration. The solar-augmented industrial process behaves as a complex system influenced by uncertainty of solar radiation, variability of demand temperature and process time schedule as well as possibility of thermal stratification in the storage. Addressing these issues to reach the most economical solution has two dimensions to it. First, the solar thermal system needs to be optimally designed. This requires the development of a performance criterion that will deliver maximum solar energy to the industrial process, avoid large variations of energy in the storage, and meet investment constraints. Second, the identified optimal system should be dynamically controlled to enable uniform heat distribution and efficient auxiliary heat utilization. This paper presents a holistic design optimization and control approach for a solar-augmented industrial process to facilitate decision support. The proposed solution is designed and optimized for a dyeing industrial process case study that resulted in a 5.7 year payback period, 56.3% solar fraction, and 252.2 tons equivalent carbon emission reduction. Furthermore by implementing dynamic control, about 12.4% increase in solar gain that led to a 5.6% reduction in payback period is identified.

This paper attempts to find, through simulation, optimum size of solar field and thermal storage for a hybrid solar-biomass cogeneration plant. The approach is to couple thermal storage to steam generating heat exchanger to enable alternate operation of solar and biomass plant. For augmenting the intermittent solar power a control strategy that module flow along with standby auxiliary heater is implemented. To this end, the cogeneration plant is modeled using the simulation and computing program TRNSYS and MATLAB. Furthermore, the overall thermal efficiency of the saturated steam generation cycle is linked to the optimization program GenOpt. The simulation calculates the optimum solar field and thermal storage size, which yields maximum overall thermal efficiency. This article demonstrates the results of a case study directed at realizing feasible alternative energy solution for Ethiopian industry.

To gain the benefits of solar-biomass cogeneration plant, supplying energy to industry, the design optimization procedure is required to holistically integrate economical, technical and environmental aspects. This entails formulation of a performance criterion that maximizes solar fraction, reduces investment cost, lowers thermal storage loss and puts less pressure on biomass resources. It is also necessary to consider factors influencing the plant’s performance while giving active role to industrial demand. This kind of optimization approach adaptively evolves as influences change and is not static. However, such a criterion is not yet part in many of the existing design optimization schemes. In this work, an alternative optimization approach that addresses the aforementioned issues is proposed. To this end, a molten salt biomass boiler is modeled in MATLAB and integrated to a solar plant model in TRNSYS. The resulting configuration is latter optimized in GenOpt to minimize biomass power utilization index (BPUI) and excess saturated steam generation (ESSG). Demonstrated by a case study, a plant efficiency of 31.5% with 23.5% solar gain is optimally designed resulting in about 0.094$/kWh levelized cost of generation. Furthermore, considering global power outage loss, the hybrid plant could be seen as a preferred industrial source of energy.

Heavy dependence on traditional fuels as well as connection to a significantly unreliable and inefficient grid (with about 20% energy loss) characterizes the Ethiopian industry. On the contrary, the country has many solar-suited industries for process heat augmentation in the low-to-medium temperature ranges. Thus, if properly designed and operated, solar thermal could give an opportunity for an efficient and cleaner alternative in these industries. This paper presents agent-based modeling (ABM) for an integrated optimization and demand side management (DSM) framework for solar-assisted industrial heating under varying load and weather condition. To demonstrate the validity and practicality of the proposed solution, a case study was conducted on Ethiopian textile industry. A payback period of 5.3 years and solar fraction of 66.7% was identified for an optimized system. Further with the implementation of DSM to guide the production policy of the industry, a 7.5% and 8.4% improvement in payback and solar fraction was achieved.

Commercial poultry production is one of the flourishing ventures of animal production in Ethiopia. It has been providing to the demands of proteins at least to the urban population, though concurrent health constraints are hampering its intended potential. This study reports the influence of infectious diseases in commercial broiler farms in central Ethiopia. In this study, clinical signs, gross lesions, laboratory tests (serology, bacterial culture, histopathology and parasitology) and farm management data were used to identify major causes of outbreaks in an age specific manner in broiler chickens in three poultry farms in Debre Zeit, Central Ethiopia. The outbreaks detected in the farms were due to mycoplasmosis, salmonellosis, colibacillosis, coccidiosis and infectious bursal disease. It is observed that the occurrence of concurrent diseases in the farms significantly affects the productivity and health status of broilers. The risk factors that predispose birds to the various infections in the different farms studied were also recorded. In addition, recommendations were also provided.