Hydro Resources Research Articles

Optimization of green hydrogen production in hydroelectric-photovoltaic grid connected power station

The escalating trend of using hydro and solar resources to generate electricity and providing green hydrogen for the transportation sector is considered as a most optimal pathway to reducing the greenhouse gas emission. As a contribution, this study focuses on optimizing the production of green hydrogen in a combined hydroelectric-photovoltaic power station located in southern Oman. The study employed a simulated model to perform techno-economic analysis and optimize the components of the hybrid power station. The model aims to optimize the components of hydroelectric photovoltaic hybrid power station connected to the power grid. The fundamental parameters to perform this analysis are the average stream flow and solar radiation. This study is depicting the production of hydrogen from a power grid as well as its utilization in conversion to green hydrogen. The economic analysis of the project depends mainly on the cost of hydro turbines, power converters, PV panels, electrolyzers and hydrogen tanks. After the overall analysis, the researchers have concluded that the net profit is playing an imperative role in optimizing the levelized cost of green hydrogen to be €2.25/kg. This analysis is providing the opportunity to the researchers to do techno-economic analysis of the hydrogen production and to utilize the produced hydrogen to facilitate green transportation thereby reducing the greenhouse gas emission.

Evaluation of surplus hydroelectricity potential in Nepal until 2040 and its use for hydrogen production via electrolysis

The abundant hydro resources in Nepal have resulted in the generation of electricity almost exclusively from hydropower plants. Several hydropower plants are also currently under construction. There is no doubt that the surplus electricity will be significantly high in the coming years. Given the previous trend in electricity consumption, it will be a challenge to maximize the use of surplus electricity. In this work, the potential solutions to maximize the use of this surplus electricity have been analysed. Three approached are proposed: (i) increasing domestic electricity consumption by shifting the other energy use sectors to electricity, (ii) cross-border export of electricity, and (iii) conversion of electricity to hydrogen via electrolysis. The current state of energy demand and supply patterns in the country are presented. Future monthly demand forecasts and surplus electricity projections have been made. The hydrogen that can be produced with the surplus electricity via electrolysis is determined and an economic assessment is carried out for the produced hydrogen. The analysis of levelized cost of hydrogen (LCOH) under different scenarios resulted values ranging from 3.8 €/kg to 4.5 €/kg.

Green hydrogen potential in tropical countries: The colombian case

Tropical countries can approach their natural resources to produce low-carbon H2 from solar, wind, hydro, and biomass resources to satisfy their domestic demand and to export it. To do so, Colombia published the National Hydrogen Roadmap, in which green H2 was prioritized. This study estimates Colombia's potential to produce green H2 and a timeline of scenarios displaying the required installed capacity, capital investment, and environmental analysis related to water utilization and CO2 capture. Accordingly, Colombia can produce H2 at a rate of 9 Mt/a by 2050 by installing 121 GW renewables while processing 303 Mt/a of residual biomass. In this scenario, Colombia's share of the H2 international market can reach 1.2%, with a cumulative investment of over 244 billion USD by 2050. This study provides insights into potential global resources for low-carbon H2 generation.

Climate-combined energy modelling approach for power system planning towards optimized integration of renewables under potential climate change - The Small Island Developing State perspective

While high renewable electricity targets are feasible under current climatic conditions, planning the power sector from a long-term perspective requires great precaution, given the strong dependency of renewable energy potential on climate and potential future changes. Power balance optimization modelling is a powerful tool for adequate power system (contingency) planning, and informed decision making in future perspective. This is demonstrated based on a case study of Suriname, considering scenario simulations and impact assessments for the 2030–2040 time horizon, for multiple load and climate projections. The recently developed REVUB modelling approach is utilized, which facilitates hourly-to-multiannual simulations, the latter being important for inter-annual variability assessments, and key for climate impact studies. Our results show that Suriname has an optimized renewable electricity share potential ranging from 50% to 90% under the considered future scenarios based on complementary exploitation of hydro, wind and solar power resources.

Incorporating grid extension into the geospatial multi-criteria analysis of the suitability of multi-renewable energy projects

Geographic information system-assisted multi-criteria analysis is the most popular approach in selecting the most suitable sites for renewable energy projects. The current practice in this approach often takes only one or two technologies at a time (mostly solar and wind), and grid extension has never been considered in the process. This paper presents a methodology for selecting sites for utility-scale renewable energy projects considering solar, wind, biomass, and hydro resources all at once. Splitting the study area according to proximity from the existing grid and extending the latter to relatively distant areas is proposed to account for the possibility that resource quality may outperform grid infrastructure investment. As a parallel research objective, the sensitivity of new (terrain ruggedness index and resource density) and traditional ranking criteria was investigated. The case study showed that a resource over 5 km away from the grid is a better project option when the grid is extended.

A Review on Renewable Energy Scenario in Ethiopia

Although Ethiopia is one of the world's fastest-growing economies, access to sustainable energy and cutting-edge clean energy technology remains a major concern. The government is making significant efforts to generate renewable energy and provide more access to its citizens. Despite this, traditional fuels (charcoal, fuel wood, dung cakes, and agricultural waste) account for around 87 percent of Ethiopia's energy use, and they pose a range of health and environmental risks. Solar, hydro, wind, and geothermal resources abound in the nation, but only 5% of the country's total hydroelectric capacity is being used; while, the rest is either underutilized or underdeveloped. An in-depth look at Ethiopia's renewable energy potential, as well as the opportunities and problems it faces, is presented in this review. With a combined installed capacity of over 7000 MW, hydropower and wind power are the most promising renewable energy sources in Ethiopia as of yet. It is hoped that this assessment will shed light on how Ethiopia can harness and maximize the use of its abundant renewable energy sources.

Assessing the Sustainability of Bitcoin Mining: Comparative Review of Renewable Energy Sources

This study conducts a comprehensive assessment of Bitcoin mining's sustainability, concentrating on the incorporation of renewable energy sources such as hydroelectric, wind, solar, and geothermal power. It investigates the adaptability and potential constructive collaboration of these energy systems in the context of the Bitcoin mining scenario. This research presents a detailed understanding of the possibilities and challenges involved with integrating hydro, wind, solar, and geothermal resources into sustainable Bitcoin mining processes by methodically examining energy efficiency, environmental effect, and economic viability. The study contributes to the discussion on establishing a sustainable future for digital currencies by exposing significant connections between renewable energy technology and the cryptocurrency industry. To achieve the stated goals, the study carefully examines the energy usage strongly associated with Bitcoin mining and transaction processing. It investigates the elements that contribute to Bitcoin's energy consumption, addressing the environmental consequences of its energy-intensive activities. The study aims to find feasible techniques for reducing Bitcoin's carbon footprint, to cultivate a thorough understanding of the complex relationship between the digital currency revolution and its environmental consequences. It emphasizes the importance of balancing technical developments with environmental responsibilities. The concept contributes to establishing a conscious and sustainable future for the digital currency ecosystem by addressing the numerous components of Bitcoin's energy usage and advocating a collective commitment to protecting the environment in the face of advancing technology paradigms.

Enhancing drought resilience and energy security through complementing hydro by offshore wind power—The case of Brazil

During atypical droughts, power systems with a heavy reliance on hydropower risk increased greenhouse gas emissions if they are balanced with fossil-fired generation. This work investigates the role of offshore wind energy in reducing the vulnerability of power systems dependent on such hydrological patterns, thereby eliminating this emission increase, using Brazil as a case study. Offshore wind potential and its complementarity with hydro resources are addressed by considering bias-corrected reanalysis data. Then, a cost-minimizing model is built to analyze the effect of integrating wind farms (considering bottom-fixed and floating structures and distance to shore) into the existing power system in Brazil. Applying a lower, median, and upper bias correction factor, potentials are reduced by 8%–44% compared to uncorrected data. Irrespective of systematic bias, the findings indicate a high complementarity between Northeastern wind regimes and most hydropower basins. The share of offshore wind energy grows in scenarios with reduced costs, but wind farms are part of the optimal system even with the current costs. With increasing wind power capacity, dynamic dispatch changes, and natural gas no longer plays a role in the dry season as it currently does, but only in the rainy season on a significantly reduced scale. Existing reservoirs support the integration of offshore wind farms into highly renewable scenarios, but they are insufficient in a complete fossil fuel phaseout, where other electricity storage must be deployed to help balance the system. Yet, power systems in the scenarios with large wind capacity have less stored hydropower in the dry season than in the current system, while they store more in the rainy season, implying a reduced risk of empty reservoirs. The Brazilian power system with offshore wind farms can eliminate 54.4 Mton CO2eq/year (97% of current power sector emissions) without additional electricity storage.

Wind, water and wires: Evaluating joint wind and interconnector capacity expansions in hydro-rich regions

Countries or regions with a high share of storage hydro and good renewables resources may be able to interconnect to less well-endowed neighbours. To maximise joint benefits, coordinating interconnector and renewables investment is desirable. Suitable long-term contracts ensure that beneficiaries pay and jointly cover the highly dispersed costs and benefits. The article develops a simple model calibrated for Tasmania that demonstrates how this can be quantified and various counterfactuals tested. The key to the simplification is that the value of water is both stable over time and the key driver of outcomes. The economic attraction of proposed wind and interconnector investment depends sensitively on the value placed on CO2 reductions.

Implications of large hydro dams for decarbonising Ghana's energy consistent with Paris climate objectives

Hydropower is a renewable source of electricity generation that is a common feature of Nationally Determined Contributions (NDC), especially in developing countries. However, far from benign, research shows that significant greenhouse gas (GHG) emissions emanate from shallow reservoirs when they are sited in the tropics. Ghana provides a case study for exploring the implications of hydro reservoir emissions within a future energy system consistent with the Paris climate objectives. Being a fast-developing country, Ghana needs to generate significant amounts of low-carbon electricity to meet growing demand over the coming 30 years. Analysis of existing Ghanaian dams (Akosombo, Kpong and Bui) and the forthcoming Pwalugu dam suggests that their average emissions intensities (gCO2/kWh) are similar to those of coal-fired power stations during the first 30 years of their operating lifetime. The case study demonstrates that cumulative (post-2020) carbon dioxide emissions from the planned and identified hydro resources will consume 40 % of Ghana's Paris-compliant carbon budget, yet provide just under 1 % of its future energy demand (under Paris-compliant scenarios). The analysis suggests that new hydropower in the tropics can significantly reduce the emission space available for other sectors such as transport and industry when faced with a highly restricted emissions budget. In conclusion, for Ghana specifically, rather than constructing more dams, energy efficiency and diversifying renewable energy supply options, including floating solar power, would deliver an energy transition for Ghana that is much more closely aligned with the Paris goals.

Innovative Solutions in Using Small Hydro Resources

The possibility of using the hydropower resources of industrial enterprise watercourses in contrast to conventional approaches to selecting watercourses for setting up small hydroelectric power plants (HPP) is considered. The watercourses used at enterprises of various industry branches were examined, and the obtained results have confirmed the technical and economic feasibility of using them for electricity generation purposes. Innovative technical and design solutions opening the possibility to construct small HPPs operating on the water streams discharged from power enterprises have been developed and are at various implementation stages. The main process equipment for electricity generation by using the industrial enterprise watercourses and for implementing the proposed design solutions has been developed and is manufactured in Russia.

Value of green hydrogen when curtailed to provide grid balancing services

This paper evaluates the potential of grid services in France, Italy, Norway and Spain to provide an alternative income for electrolysers producing hydrogen from wind power. Grid services are simulated with each country's data for 2017 for energy prices, grid services and wind power profiles from relevant wind parks. A novel metric is presented, the value of curtailed hydrogen, which is independent from several highly uncertain parameters such as electrolyser cost or hydrogen market price. Results indicate that grid services can monetise the unused spare capacity of electrolyser plants, improving their economy in the critical deployment phase. For most countries, up-regulation yields a value of curtailed hydrogen above 6 €/kg, over 3 times higher than the EU's 2030 price target (without incentives). However, countries with large hydro power resources such as Norway yield far lower results, below 2 €/kg. The value of curtailed hydrogen also decreases with hydrogen production, corresponding to the cases of symmetric and down-regulation.

Feasibility Analysis and Economic Viability of Standalone Hybrid Systems for Marudi Electrification in Sarawak, Malaysia

A hybrid renewable energy system is a feasible solution for off-grid electrification where grid electricity is not available due to economic or technical limitations. In this study, rural electrification is performed on a small longhouse settlement, Long Moh, in Sarawak, Malaysia, with a population of 308 from 70 households. Initially, a hybrid PV/Hydro/DG/Battery system is proposed due to the abundance of solar and hydro resources in the village. There have been a lot of studies based on PV/DG/Battery systems in Malaysia but less with the inclusion of hydropower. Through simulation and optimization process, the most optimal system in terms of Net Present Cost (NPC) is found to be a hybrid Hydro/DG/Battery system which provides a total NPC of $213,694.90, cost of electricity of $0.08/kWh, and operating cost of $9,495.56/year. The most environmentally friendly system is the proposed PV/Hydro/DG/Battery system due to less fuel consumption (12,863.63 L/year) and its high renewable penetration. The standalone diesel generator (DG) system was the least economic and most polluting system. The best system overall for rural electrification at the case study location is a hybrid Hydro/DG/battery system due to its relatively low NPC and emissions output compared to a standalone DG system.

МОДЕЛЬ ОПТИМАЛЬНОГО ВИКОРИСТАННЯ РЕСУРСІВ ГІДРОЕЛЕКТРОСТАНЦІЙ НА РИНКУ ЕЛЕКТРИЧНОЇ ЕНЕРГІЇ

A mathematical model for optimizing the activity of the PJSC «Ukrhydroenergo» cascade of hydroelectric power plants in the segments of the electricity market is described. This model is built taking into account the limitations on the use of available water resources. The structure of the mathematical model as an objective function of maximizing the benefits of electricity sale and the system of restrictions of equality and inequality is presented. This function takes into account the economic and technical characteristics of power plant equipment, as well as the balance of hydro resources. Peculiarities of taking into account prices in electricity market segments are shown. The main technological constraints of hydraulic units and power plants are described. The structure of the system of restrictions on the use of water resources is reflected, taking into account changes in the levels of reservoir occupancy. The main approaches to the use of the proposed model to solve the problems of planning the participation of the cascade of hydropower plants in the auction of the electricity market are presented. References 16, figures 2.

Towards the Hydrogen Economy in Paraguay: Green hydrogen production potential and end-uses

This study was conducted to estimate the potential for green H2 in Paraguay. A total production potential of 22.5 × 106 tons/year was obtained with a main contribution (93.34%) from solar photovoltaic. The greatest potential for producing H2 from solar and wind resources is in the Western region, and from hydro resources is in the Eastern region of the country. Two end-uses of green H2 were assessed: (1) automotive transportation, replacing gasoline and diesel; and (2) residential energy, replacing firewood and LPG for cooking in households across the country. In 16 of the 17 departments, green H2 is able to replace the overall consumption of gasoline and diesel, as well as firewood and LPG. Finally, energy service cost (mobility), environmental aspects and CO2 emissions were considered for three urban mobility technologies for the Metropolitan Area of Asunción. Results show that the mobility cost of fuel cell hybrid electric buses is still very high in comparison to diesel buses and battery electric buses. However, when a longer driving range is required, fuel cell hybrid electric buses could become a viable alternative in the long term. From an environmental point of view, green H2 used in fuel cell hybrid electric buses has the potential to save about 96% of CO2 emissions in comparison to diesel buses. It is concluded that the estimated green H2 production potential favors the incorporation of the Hydrogen Economy in Paraguay.

ДОБОВА ОПТИМІЗАЦІЯ ГРАФІКУ РОБОТИ ГІДРОЕЛЕКТРОСТАНЦІЇ НА РИНКУ «НА ДОБУ НАПЕРЕД»

A mathematical model of the daily optimization of available hydro resources of hydropower plants is presented as a tool for solving the problem of determining hourly volumes of electricity sales in the «day ahead» market segment, taking into account technological limitations and volumes of electricity under already concluded agreements. The method of preparation of input data in the part of calculations of the coefficients of the objective function and the system of constraints is presented. An example of solving the problem of daily optimization of the available hydro resources of the Kyiv HPP is demonstrated and the need to use additional non-price optimization criteria is substantiated. Bibl. 7, figure.

მდ. ტეხურის ხეობის ზემო წელის საინჟინრო-გეოლოგიური პირობები

The economic development of modern Georgia is closely related to the development of exogenous energy resources (water, solar and wind). Among them, the great potential for the existence and development of hydro resources is especially noteworthy. One of the important bases for the development of hydropower resources is the construction and operation of hydraulic structures in a geologically sustainable environment. Special attention should be paid to the very interesting Tekhuri River gorge. Studying engineering-geological features of the area is closely related to the construction of the planned cascade of hydropower plants (Lechekha, Erjia, Khifa, Tskhimra, Nobulevi) along the 21 km section of the Tekhuri River gorge (from Lebarde resort to the village of Nobulevi). Moreover, detailed engineering-geological mapping, determination of physical-mechanical properties of rocks and soils and their statistical analysis were carried out. In addition, the first attempt to calculate data on a relatively new classification of rock masses, Geological Stiffness Index (GSI) data for the territory of Georgia using RMR is described.

Assessment of Canada's electricity system potential for variable renewable energy integration

Meeting commitments to the Paris Agreement will necessitate a transition in Canada's power system including increased generation from renewable sources. This study analyzes the Canadian electricity system in terms of its readiness to operationalize decarbonization strategies. More specially, this paper evaluates potential of Canada's electricity system in terms of the flexibility required to integrate variable renewable energies (VREs). To do so, the SILVER production cost model (PCM) is refined to improve its representation in terms of hydro resources, demand response programs and price-setting mechanism. Next, a network-constrained unit commitment (NCUC) of SILVER is built for each of Canada's ten provinces for a one-year period based on 2018 data. The results are used to assess the system flexibility and transmission network sufficiency as well as operational aspects including costs and emissions. The results indicate the SILVER's improved hydro modelling enhances the result of operation model by 4% on average. Also, the results demonstrate high flexibility of Canada's hydro-dominated network side along with free capacity in the transmission network can realize 54% VREs penetration rate on average for VREs curtailment less than 10%. In addition, implementation of demand side programs improves the VREs penetration rate by 2%–6% on average.

The role of U.S.-Canada electricity trade in North American decarbonization pathways

We investigate the role of U.S.-Canada electricity interconnections in supporting decarbonization efforts toward addressing both countries’ emission reduction goals. Using the OSeMOSYS energy system model, we calculate the generation mix and required transmission expansion between Canada and the U.S. under six climate policy and transmission cost scenarios. Overall, current emission prices will not provide enough incentive to meet stated emission reduction goals. Increases in emission penalties lead to increased transmission capacity. In all cases, the system requires significant dispatchable, low-carbon electricity to meet emission reduction goals and the flexibility of hydro resources provides significant system value. In addition to hydro and low-carbon dispatchable generation, the system requires significant investments in wind and solar in all scenarios.

Models of Optimal Operating Modes of the Water-Economic Complex on the Basis of Hydro Resource Price Evaluation

The purpose of this article is to solve the problem of determining the cost of a water resource for the participants of the water-economic complex (WEC) on the basis of the optimal control of hydro power plants’ (HPP) functioning, taking into account their regime characteristics and requirements. In this work, a universal method, which combines an optimization method and a method for assessing marginal utility, was proposed to assess the cost of the hydro resource and control the operating modes of the WEC. The method developed by the authors involves the use of water balance, the adequate representation of the incremental rate characteristic and the determination of the cost of the hydro resource for the control of the operating modes of the WEC and HPP. Using the example of the Novosibirsk WEC, as well as HPPs and TPPs, an assessment of the energy efficiency, proposing the concept of a developed methodology for determining the price of water for HPPs and all participants in the WEC, will be obtained. Based on the results of the implementation of the developed approach at Novosibirsk HPPs, the electricity sales price competitive electricity market can be matched with the electricity sales price generated at TPP, which will be approximately 0.16 ¢/kW ∗ h.