Optimizing renewable-based energy supply options for power generation in Ethiopia

Ethiopia unveiled homegrown economic reform agenda aimed to achieve a lower-middle status by 2030 and sustain its economic growth to achieve medium-middle and higher-middle status by 2040 and 2050 respectively. In this study, we evaluated the optimal renewable energy mix for power generation and associated investment costs for the country to progressively achieve upper-middle-income countries by 2050. Two economic scenarios: business as usual and Ethiopia’s homegrown reform agenda scenario were considered. The study used an Open Source energy Modeling System. The model results suggest: if projected power demand increases as anticipated in the homegrown reform agenda scenario, Ethiopia requires to expand the installed power capacity to 31.22GW, 112.45GW and 334.27GW to cover the current unmet and achieve lower, medium and higher middle-income status by 2030, 2040 and 2050 respectively. The Ethiopian energy mix continues to be dominated by hydropower and starts gradually shifting to solar and wind energy development towards 2050 as a least-cost energy supply option. The results also indicate Ethiopia needs to invest about 70 billion US$ on power plant investments for the period 2021–2030 to achieve the lower-middle-income electricity per capita consumption target by 2030 and staggering cumulative investment in the order of 750 billion US$ from 2031 to 2050 inclusive to achieve upper-middle-income electricity consumption rates by 2050. Ethiopia has enough renewable energy potential to achieve its economic target. Investment and financial sourcing remain a priority challenge. The findings could be useful in supporting decision-making concerning socio-economic development and investment pathways in the country.

Hydrogenation and Dehydrogenation of Liquid Organic Hydrogen Carriers: A New Opportunity for Carbon-Based Catalysts

The development of a hydrogen-based economy is the perfect nexus between the need of discontinuing the use of fossil fuels (trying to mitigate climate change), the development of a system based on renewable energy (with the use of hydrogen allowing us to buffer the discontinuities produced in this generation) and the achievement of a local-based robust energy supply system [...]

Intelligent Control on Urban Natural Gas Supply Using a Deep-Learning-Assisted Pipeline Dispatch Technique

Natural gas has been attracting increasing attentions all around the world as a relatively cleaner energy resource compared with coal and crude oil. Except for the direct consumption as fuel, electricity generation is now another environmentally-friendly utilization of natural gas, which makes it more favorable as the energy supply for urban areas. Pipeline transportation is the main approach connecting the natural gas production field and urban areas thanks to the safety and economic reasons. In this paper, an intelligent pipeline dispatch technique is proposed using deep learning methods to predict the change of energy supply to the urban areas as a consequence of compressor operations. Practical operation data is collected and prepared for the training and validation of deep learning models, and the accelerated predictions can help make controlling plans regarding compressor operations to meet the requirement in urban natural gas supply. The proposed deep neutral network is equipped with self-adaptability, which enables the general adaption on various temporal compressor conditions including failure and maintenance.

Mobile Off-Grid Energy Generation Unit for Temporary Energy Supply

Temporary structures are being extensively used by emergency services (rescue, disaster relief, military response units), and other end-users requiring temporary mobile off-grid energy solutions for different purposes (event organization, vacation homes, summer camps, etc.). Yet energy systems for these purposes largely remain fossil-based (such as diesel generators). Although such energy systems are inexpensive, they are carbon intensive and inefficient. This study presents a methodology of simulating temporary shelter with access to an energy supply system through a mobile energy unit with renewable (PV) power supply systems to ensure on-site electricity production, as well as heating/cooling and ventilation. Digital modeling simulations have been performed for a simulated temporary shelter in different climate conditions incorporating different combinations of electricity generation systems with a fossil fuel-based solution and a PV system, using TRNSYS software. Study results show that the operation of a mobile energy generation unit can operate HVAC systems and generate electricity for temporary shelter occupants in off-grid solutions. The modeling results show that the use of a mobile energy generation unit can significantly reduce diesel consumption in temporary shelters from 54% annually (in Riga, Latvia) to 96 % annually (in Jerusalem, Israel). Furthermore, the output of PV-generated electricity is higher (in most cases) than the consumed electricity amount.

Determination of average relative capital investment of 30–125 MW combined-cycle plants commissioned at Russian thermal power plants in 2015–2020. Comparative analysis with data obtained in 2010–2014

The present work examines average relative capital investment and fuel consumption for electric and thermal energy supply of the combined-cycle plants having 30–125 MW gas turbines commissioned at Russian thermal power plants in 2015–2020. In this work, we used general calculation methods of average relative capital investments and fuel consumption for the electrical and thermal energy supply using power equipment of thermal power plants. To assess the scope of commissioning gas turbines incorporated into the combined-cycle plants, they were classified into three groups by electrical power: 30–59 MW, 60–99 MW and 100–125 MW. The scope of commissioning gas turbines incorporated into the Russian combined-cycle plants in 2015–2020 was analysed. The average relative capital invest-ment in combined-cycle plants having 30–125 MW gas turbines, as well as the average specific fuel consumption for the electrical and thermal energy supply, were calculated. The calculations were carried out for each part of combined-cycle plants integrated into thermal power plants with a breakdown by seven Unified Energy Systems of Russia. The quantita-tive commissioning of gas turbines is compared for the periods from 2010 to the economic crisis of 2014 and after 2014 to the present: a ~2.5-fold decrease is demonstrated. A preliminary evaluation of the increase in average relative capital investment in combined-cycle plants having gas turbines of the same electric power was performed.

СТАН ТА ТЕНДЕНЦІЇ РОЗВИТКУ СИСТЕМИ ЕНЕРГОЗАБЕЗПЕЧЕННЯ В УКРАЇНІ

The article discusses contemporary issues of ensuring energy security in Ukraine. A brief overview on the modern energy system which comprises power plants of different types, electrical and thermal networks operating in the manufacturing sector, in transmission and distribution of electrical and thermal energy. The study considers the following types of power plants in the energy system of Ukraine: nuclear, thermal, hydroelectric and hydropower stations as well as power plants working with alternative (renewable) energy sources. It is argued that the ratio of energy sources and the energy system balance is the core basis to provide the national energy security and maintain stable power supply subject to different external environment factors. The findings have revealed the dominance of coal and natural gas production in the overall energy balance of Ukraine. However, the study of import and export trends demonstrates the prevalence of energy imports, in particular coal, oil and gas. It is observed that currently, alternative energy sources are at the infant development stage. The study of alternative energy supply in Ukraine shows that over 2018–2020 the capacity of such power plants increased by 7%, in particular, the capacity of wind stations grew by 2.3 times and solar – by 4.3 times, thus exhibiting respective change in energy output. It is also observed that during the period under consideration, the renewable energy output dropped by 17.1% while wind power production increased by 2.8 times and solar – by 5.2 times, respectively. According to the results, over 2018–2020 the capacity of wind power plants increased from 0.9% to 2.0% of the total domestic output, and solar – from 2.3% to 9.4%; as to production, the share of energy generated by wind power increased from 0.8% to 2.4%, and solar – from 0.7% to 4.1%. Given the current trend of increasing energy output generated from alternative sources, there is reason to tap a growing interest in the activities of companies offering power generating equipment in the Ukrainian market. A study on the capacity needs has revealed that the most popular among consumers of autonomous power supply systems, about 70% of total sales refer to low and medium power generators in the range of 8–550 kW. The conclusions resume that the key driver in boosting the alternative energy supply system is the relevant legal framework that encourages further alternative energy supply market development and, accordingly, the market of power generating equipment in Ukraine characterized by a strong upward growth trend.