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Hydroenergy is developed due to its low-cost and near-zero pollution emission properties; therefore, the efficient management of hydroenergy is an important goal of sustainable development for any nation, especially for China, since it owns the most abundant water resources around the world. Developing hydroenergy is not only an effective response to the energy crisis but also a positive way to cope with climate change in China. Nevertheless, research on hydroenergy in China is still not comprehensive. This study reviews hydroenergy development in China by combining its geographical characteristics and hydroenergy reserves. The general condition of hydropower development including large- and medium-scale hydropower stations and small hydropower development is presented. This article illuminates the potential problems and existing challenges in China’s hydropower development and relevant exploitation suggestions are provided for hydropower development in the future.

Emissions associated with hydropower are often forgotten. Lifecycle assessments of greenhouse gas emissions emanating from hydropower must count embedded carbon, emissions from reservoir lakes and the loss of carbon sinks, as well as backup diesel generation emissions when dependence on hydropower fails to deliver energy. Using Zambia as a case study, we estimate using a bottom-up approach that the emissions associated with backup diesel generation from Zambia's power utility ZESCO and three largest sectors of consumers were up to 27 000 tonnes of CO2 in the worst months of drought in 2019. This is significantly higher than what a previous top-down approach would have estimated. We worked out ZESCO's diesel generation attributable to drought using trend analysis. We worked out the mining sector's emissions using copper production data, on-grid electricity consumption and calculated electricity intensity to infer off-grid electricity consumption in years of drought. From our household survey we learned average duration of generator use, average capacities of generators and acquired household income and generator use data which we ran in a Tobit regression. These together with labour force survey data helped us infer the level of diesel generation by households of different income brackets. For manufacturing firms we surveyed 123 firms. We collected rich diesel generation use data covering years of drought, input this into an OLS regression to identify predictors of diesel generation use (installed capacity of generator in kVA, in litres and whether generation was in a drought year) which we then used to extrapolate implied diesel generation for the firms for which we had less rich data. As global average temperatures and the frequency of El Niño droughts rise in hydropower dependent countries which account for a fifth of the world's population, backup generation emissions have implications for the formulation of low carbon energy policy.

Hydropower is among the cleanest sources of energy. However, the rate of hydropower generation is profoundly affected by the inflow to the dam reservoirs. In this study, the Grey wolf optimization (GWO) method coupled with an adaptive neuro-fuzzy inference system (ANFIS) to forecast the hydropower generation. For this purpose, the Dez basin average of rainfall was calculated using Thiessen polygons. Twenty input combinations, including the inflow to the dam, the rainfall and the hydropower in the previous months were used, while the output in all the scenarios was one month of hydropower generation. Then, the coupled model was used to forecast the hydropower generation. Results indicated that the method was promising. GWO-ANFIS was capable of predicting the hydropower generation satisfactorily, while the ANFIS failed in nine input-output combinations.

The Kemi River is the major watercourse in the Finnish province of Lapland and the »stream of life« for the inhabitants of its banks. Franz Krause examines fishing, transport and hydropower on the Kemi River and analyses the profoundly rhythmic patterns in the river dwellers' activities and the river's dynamics. The course of the seasons and weekly and daily rhythms of discharge, temperature, work and other patterns make the river dwellers' world an ever-transforming phenomenon. The flows of life and the frictions of everyday encounters continually remake the river and its inhabitants, negotiating national strategies, economic power, people's ingenuity, and the currents of the Kemi River.

Dams contribute to water security, energy supply, and flood protection but also fragment habitats of freshwater species. Yet, a global species-level assessment of dam-induced fragmentation is lacking. Here, we assessed the degree of fragmentation of the occurrence ranges of ∼10,000 lotic fish species worldwide due to ∼40,000 existing large dams and ∼3,700 additional future large hydropower dams. Per river basin, we quantified a connectivity index (CI) for each fish species by combining its occurrence range with a high-resolution hydrography and the locations of the dams. Ranges of nondiadromous fish species were more fragmented (less connected) (CI = 73 ± 28%; mean ± SD) than ranges of diadromous species (CI = 86 ± 19%). Current levels of fragmentation were highest in the United States, Europe, South Africa, India, and China. Increases in fragmentation due to future dams were especially high in the tropics, with declines in CI of ∼20 to 40 percentage points on average across the species in the Amazon, Niger, Congo, Salween, and Mekong basins. Our assessment can guide river management at multiple scales and in various domains, including strategic hydropower planning, identification of species and basins at risk, and prioritization of restoration measures, such as dam removal and construction of fish bypasses.

Archimedes Screws Turbines (ASTs) are a new form of small hydroelectric powerplant that can be applied even in low head sites. ASTs offer a clean and renewable source of energy and are safer for wildlife and especially fish than other hydro generation options. As with other energy solutions, ASTs are not a global solution for all situations. However, in terms of sustainable development, ASTs can offer many economic, social, and environmental advantages that make them an important option for providing sustainable hydropower development. Archimedes screws can operate in low water heads (less than about 5 m) and a range of flow rates with practical efficiencies of 60% to 80% and can generate up to 355 kW of power. ASTs increase the number of suitable sites where it is possible to develop sustainable hydropower, including in undeveloped, hard to access regions and small communities. At many low head sites, ASTs may be more cost-effective, with lower installation and operating costs than alternative hydropower systems. An AST may also reduce the disturbance of natural sedimentation and erosion processes and have smaller impacts on fish and other fauna. ASTs can often be retrofit to existing unpowered dams or weirs, providing new hydropower capacity for very little marginal environmental impact. This review outlines the characteristics of ASTs, then discusses and analyzes how they could benefit the sustainability of hydropower development.

Hydropower has been the leading source of renewable energy across the world, accounting for up to 71% of this supply as of 2016. This capacity was built up in North America and Europe between 1920 and 1970 when thousands of dams were built. Big dams stopped being built in developed nations, because the best sites for dams were already developed and environmental and social concerns made the costs unacceptable. Nowadays, more dams are being removed in North America and Europe than are being built. The hydropower industry moved to building dams in the developing world and since the 1970s, began to build even larger hydropower dams along the Mekong River Basin, the Amazon River Basin, and the Congo River Basin. The same problems are being repeated: disrupting river ecology, deforestation, losing aquatic and terrestrial biodiversity, releasing substantial greenhouse gases, displacing thousands of people, and altering people’s livelihoods plus affecting the food systems, water quality, and agriculture near them. This paper studies the proliferation of large dams in developing countries and the importance of incorporating climate change into considerations of whether to build a dam along with some of the governance and compensation challenges. We also examine the overestimation of benefits and underestimation of costs along with changes that are needed to address the legitimate social and environmental concerns of people living in areas where dams are planned. Finally, we propose innovative solutions that can move hydropower toward sustainable practices together with solar, wind, and other renewable sources.

The Balkan Peninsula is considered to be a biodiversity hotspot, hosting a particularly high number of endemic species. Despite increased faunistic research in recent decades many areas remain poorly investigated, particularly regarding the aquatic entomofauna. The order Plecoptera, for instance, is strongly associated with cold, well-oxygenated mountain rivers and is known for its high sensitivity to environmental change. Consequently, stoneflies serve as valuable bioindicators in environmental monitoring. Similarly, the order Trichoptera includes many species with high habitat specificity, which are vulnerable to habitat degradation. A comprehensive understanding of the region's species inventory is essential, not only to deepen the knowledge about the distribution and habitat preferences of endemic and rare species, but also to assess what is at stake in case of significant environmental changes, such as those caused by hydropower development. To address these gaps in our knowledge, faunistic surveys focusing on Plecoptera and Trichoptera were conducted in 2022 and 2023 along the upper reaches of the Neretva River and its tributaries Krupac, Ljuta, and Jezernica as well as smaller, unnamed brooks within the catchment. Here we report the results from 2023 and compare them to the data published in 2022; both surveys conducted as part of the Neretva Science Week. We aim to contribute to the broader understanding of species diversity, distribution, and abundance of Plecoptera and Trichoptera in this area. Balkanski polotok velja za žarišče biotske raznovrstnosti z izjemnim številom endemičnih vrst. Kljub povečanim raziskavam favne v zadnjih desetletjih so mnoga območja še vedno slabo raziskana, zlasti kar zadeva vodne žuželke. Red Plecoptera je na primer močno povezan s hladnimi, dobro oksigeniranimi gorskimi rekami in je znan po svoji visoki občutljivosti na okoljske spremembe. Posledično so vrbnice dragoceni bioindikatorji pri spremljanju okolja. Podobno red Trichoptera vključuje številne vrste z visoko specifičnostjo habitata, ki so posledično ranljive za degradacijo habitata. Celovit popis vrst v regiji je bistven za razumevanje razširjenosti in habitatnih preferenc endemičnih in redkih vrst, kot tudi za oceno, kaj je na kocki v primeru pomembnih okoljskih sprememb, kot so tiste, ki jih povzroča razvoj hidroelektrarn. Da bi odpravili te vrzeli v znanju, so bile v letih 2022 in 2023 izvedene raziskave favne, osredotočene na vrbnice in mladoletnice vzdolž zgornjega toka reke Neretve in njenih pritokov Krupac, Ljuta in Jezernica, pa tudi manjših, neimenovanih potokov znotraj porečja. Tukaj poročamo o rezultatih iz leta 2023 in jih primerjamo z že objavljenimi podatki iz leta 2022, pri čemer sta obe raziskavi del Tednov znanosti Neretve. S tem želimo prispevati k širšemu razumevanju vrstne raznolikosti, razširjenosti in številčnosti vrbnic in mladoletnic na tem območju. Apstrakt. Vrste redova Plecoptera i Trichoptera u gornjem slivu rijeke Neretve (Bosna i Hercegovina): novi podaci iz 2023. godine dopunjuju visok diverzitet zabilježen već prethodne godine – Balkansko poluostrvo se smatra žarištem biodiverziteta, domaćinom posebno velikog broja endemskih vrsta. Uprkos povećanim istraživanjima faune u poslednjim decenijama, mnoga područja su i dalje slabo istražena, posebno kada je u pitanju vodena entomofauna. Red Plecoptera, na primer, snažno je povezan sa hladnim, dobro oksigeniranim planinskim rijekama i poznat je po svojoj visokoj osetljivosti na promene u okruženju. Shodno tome, kamenjarke služe kao vredni bioindikatori u praćenju životne sredine. Slično tome, red Trichoptera uključuje mnoge vrste sa visokom specifičnošću staništa, koje su posljedično ranjive na degradaciju staništa. Sveobuhvatno razumjevanje inventara vrsta u regionu je neophodno, ne samo da bi se produbilo znanje o rasprostranjenosti i preferencijama staništa endemskih i retkih vrsta, već i da bi se procenilo šta je u pitanju u slučaju značajnih promena u okruženju, kao što su one izazvane izgradnjom hidroenergije. Da bi se popunili ovi nedostaci u znanju, faunistička istraživanja usmerena na Plecoptera i Trichoptera sprovedena su 2022. i 2023. godine duž gornjeg toka rijeke Neretve i njenih pritoka Krupac, Ljuta i Jezernica, kao i manjih, neimenovanih potoka unutar sliva. Ovde izveštavamo o rezultatima iz 2023. godine i upoređujemo ih sa već objavljenim podacima iz 2022. godine, pri čemu su oba istraživanja dio Sedmice nauke na Neretvi. Ovim ciljamo da doprinesemo širem razumjevanju raznolikosti vrsta, rasprostranjenosti i brojnosti kamenjarki (Plecoptera) i dlakokrilaca (Trichoptera) u ovom području.

As the effects of climate change are becoming severe, countries need to substantially reduce carbon emissions. Small hydropower (SHP) can be a useful renewable energy source with a high energy density for the reduction of carbon emission. Therefore, it is necessary to revitalize the development of SHP to expand the use of renewable energy. To efficiently plan and utilize this energy source, there is a need to assess the future SHP potential based on an accurate runoff prediction. In this study, the future SHP potential was predicted using a climate change scenario and an artificial neural network model. The runoff was simulated accurately, and the applicability of an artificial neural network to the runoff prediction was confirmed. The results showed that the total amount of SHP potential in the future will generally a decrease compared to the past. This result is applicable as base data for planning future energy supplies and carbon emission reductions.

Sub-Saharan Africa has been at the epicenter of an ongoing global dialogue around the issue of energy poverty. More than half of the world’s population without access to modern energy services lives there. It also happens to be a sub-continent with plentiful renewable energy resource potential. Hydropower is one of them, and to a large extent it remains untapped. This study focuses on the technical assessment of small-scale hydropower (0.01–10 MW) in Sub-Saharan Africa. The underlying methodology was based on open source geospatial datasets, whose combination allowed a consistent evaluation of 712,615 km of river network spanning over 44 countries. Environmental, topological, and social constraints were included in the form of constraints in the optimization algorithm. The results are presented on a country and power pool basis.