The assessment of environmental impacts of renewable energy technologies used in Rwanda

Abstract

In Rwanda, the development of renewable energy technology projects tends to be large-scale and also applicable in rural and remote areas, where energy is often critical for human development because energy services have an impact on productivity, health, education, safe water, communication services and electrification, as most renewable energy technologies typically convert energy into electricity, thereby providing power grids and stand-alone power systems for the country. Recently, scientific research and development have been focusing on the development of renewable energy technology projects and protecting renewable resources, to solve the global energy crisis and improve energy generation and utilization. Climate change affects Rwanda's current patterns of energy production and consumption. Because of seasonal changes (dry and rainy seasons), renewable energy, especially sunlight and water used in renewable energy power plants, can have a significant impact on power plant performance, and socioeconomic and environmental management. Charcoal from trees does not have a net contribution to greenhouse gas emissions and climate change because the CO2 released during burning is the same CO2 consumed by the tree during its lifetime. Furthermore, burning of firewood and other biomass feedstock such as happens in tea factories, brick making and other industrial activities does not constitute greenhouse gas emission. However, there are other impacts such as deforestation and indoor pollution caused by the use of charcoal. The purpose of this study was to assess the environmental impact of renewable energy technologies used in Rwanda. In particular, the study emphasizes on the environmental audit of various power plants such as hydropower, solar and biomass. The benefits and negative impacts of the mentioned energy sources and various proposed mitigation measures, as well as socioeconomic and environmental impacts are presented in detail. Various methods have been used to achieve research objectives, including surveys, fieldwork, observations, interviews, and qualitative and quantitative methods. Data analysis and visualization were explored using Python, Excel and Orgin8. The link between renewable energy generation and climate change was also examined using meteorological data. This study attempts to analyse the current status of environmental impact assessment, focusing on environmental audit of renewable energy technologies and proposing the mitigation measures for the identified negative impacts. Hydropower accounts for 43.9% of the current total electricity generation in Rwanda, and the research found that storage hydropower plants (Ntaruka, Mukungwa I) have significant negative environmental impacts on fish damage and production, as well as downstream water quality. Run-of-river hydropower plants (Nyabarongo I & II) have less of an environmental impact, but there is also the issue of sands and sediments building up in reservoirs or dams, which have a long negative impact on time and also negatively iii impact on the power plant generation. In case of hydropower generation, there are negative environmental impacts such as the impact noise of rotating turbine blades, disrupting local ecosystems. In addition, climate change has also a significant negative impact on the hydropower generation, dry seasons are getting longer and more severe and thus resulting in more severe reductions in the river flows, reducing power generation, and sediment loading and soil erosion reaching maximum yields during heavy rainy seasons and there is an incident that happens unexpectedly and unintentionally, typically resulting in damage or injury, and also moderate negative impacts during the power plant operations. Solar technologies account for 4.2% of the total electricity currently generated and the research has found that these technologies have environmental benefits, negative impacts and positive socioeconomic impacts such as; noise, visual impairment, energy consumption, industrial accidents, biodiversity, water and soil pollution. Rwanda's electrification access rate has been scaled up from 10% in 2010 to 65% in mid-2021, this shows the socioeconomic benefits by increasing the country's energy independence and reducing the number of transmission lines required for the grid. Compared to other types of renewable energy technologies, the technology has significant environmental benefits and offers significant benefits in terms of employment opportunities. Biomass accounts for 85% of all energy consumed and the research found that continuing to use biomass energy as a cooking fuels, this has negative environmental impacts leading to accelerated deforestation and land degradation, erosion, landslides, water quality, and biodiversity loss. The results show that the development of biogas produced from agricultural waste is rather slow due to the initial investment costs required to start production. The renewable energy projects and development have brought significant benefits, including rural electrification, decrease fuel and electricity costs, improved grid reliability and increased employment opportunities. The benefits of using these technologies are to produce energy that produces minimum greenhouse gas emissions, reduce some other types of air pollution, and reduce dependence on imported fuels. Renewable energy generation depends on climate changes, but attention to environmental impacts should also be considered and innovative energy storage needs to take place when planning for future energy generation. The impacts of noise during the power plant generation can be minimized through different technologies and techniques. The information and insights generated here are critical for policymakers to develop new environmental management policies and strategies The author has recommended the area of further research on comparative environmental audits of renewable energy and non-renewable energy generations. The government of Rwanda must control and maintain existing regulations and propose a new policy to control erosion and sediment through agroforestry and forest restoration