This study was carried out in Woreta Zuria village, around Woraeta town, the capital of Fogera woreda with the objectives of evaluating of current status of traditional biomass energy utilization, assessment of biogas potential in the Amhara region and estimating the amount of biogas required to substitute the traditional biomass energy, including designing and description of a biogas plant.
The major source of data for the analysis was the result of household survey conducted within Woreta Zuria village in which it was intended to be the beneficiary. The procedure employed in the survey was first that15 households were selected by systematic sampling method and primary data were collected by types and sources of energy for domestic use.
Fuelwood and cattle dung cake were the most dominant traditional biomass fuel sources utilized by the households in the study area. For the average household with five members, fuelwood and dung cake consumption for cooking was 5.9 kg and 5.0 kg respectively while, the daily kerosene use was 0.13 liter.
The intention of this study was to estimate the required biogas energy to replace the current use of the traditional biomass energy use. So, fresh dung was measured in each household for all normal sized sedentary adult cattle and it was found that daily average dung collected from single cattle was around 9 kg.
In the household having 5 family members, the average overall energy consumed from all energy sources, including kerosene for lighting aggregates to 176.7 MJ. The equivalent amount of biogas to replace this traditional energy use for the household was estimated to 1.73 m3 n with daily input of 36 kg of fresh substrate (cow dung and human feces).
The biogas plant to produce the same amount of biogas was designed to be 6 m3 with a total construction cost of 12007 ETB. This study shows that installing a 6 m3 biogas plant will have fuel related savings of about 2197 ETB per year, from both cooking and lighting fuel expenditures at household level. The annual bio-slurry produced per household from a 6 m3 volume biogas plant was estimated to be around 26280 kg, which has a financial value of 1703 ETB fertilizer benefit.
The annual financial health benefits due to clean energy and improved sanitation of the biogas plant was aggregated to 674 ETB at the household level. In this study, the annual fuelwood, dung cake and kerosene saved was estimated to be 2154 kg, 1825 kg, and 47.43 liters respectively for the household. These savings can reduce 6.1 tons of CO2 emission and could save 0.36 ha of forest land that would have a total equivalent amount of 2795 ETB from car bon reduction and aforestation costs.
The financial net present value of the biogas plant was 16201 ETB, while the economic net
present value was 59951 ETB, which means that investing on the biogas plant would have higher return to the household than investing on the capital market.
Author: Simur Asres, Tsigie