*Editorial* **Advancements in Hydropower Design and Operation for Present and Future Electrical Demand**

**John Cimbala <sup>1</sup> and Bryan Lewis 2,\***


With the current infrastructure, meeting the ever-growing demand for electrical energy across the globe is becoming increasingly difficult. The widespread adoption of both commercial and residential non-dispatchable renewable energy facilities, such as solar and wind, further taxes the stability of the electrical grid, often causing traditional fossil fuel power plants to operate at lower efficiency, and with increased carbon emissions. Hydropower, as a proven renewable energy technology, has a significant part to play in the future global electrical power market, especially as increasing demand for electric vehicles will further amplify the need for dispatchable energy sources during peak charging times. Even with more than a century of proven experience, significant opportunities still exist to expand the worldwide hydropower resources and more efficiently utilize existing hydropower installations.

Given this context, this Special Issue of *Energies* was intended to present recent developments and advancements in hydropower design and operation. This Special Issue includes five articles, authored by international research teams from Japan, Pakistan, Sweden, Norway, the United States, and China. The authors bring the collective expertise of government research laboratories, university professors, industry research engineers, computer scientists, and economists. The articles explore advancements in hydroturbine and pump-turbine design, power plant operation, auxiliary equipment design to mitigate environmental damage, and an exploration of community-owned small hydropower facilities.

The articles contained in this Special Issue are:


To conclude, the future of the global energy industry, while difficult to predict, will undoubtably include an ever-increasing portfolio of renewable energy sources. Hydroturbine and pump-turbine design engineers continue to find new improvements in efficiency [1–3]. As a result of ever-advancing system operations and control [4], hydropower will continue to be a major electricity contributor, given its historically proven reliability. The ability to dispatch energy generation when needed is a key element of maintaining stable electrical power grids to support growing global electrical demand. Many locations worldwide have significant untapped hydropower potential that will likely be developed in the coming

**Citation:** Cimbala, J.; Lewis, B. Advancements in Hydropower Design and Operation for Present and Future Electrical Demand. *Energies* **2022**, *15*, 2362. https:// doi.org/10.3390/en15072362

Received: 11 March 2022 Accepted: 21 March 2022 Published: 24 March 2022

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decades [5]. The successful future of worldwide electrical energy production and distribution will require collaboration among governments, environmental agencies, corporations, and researchers.

**Author Contributions:** Project administration, J.C.; Writing—original draft, B.L.; Writing—review and editing, J.C. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** The editors of this Special Issue are grateful to the MDPI Publisher for the invitation to act as Guest Editors of this Special Issue. All authors are indebted to the editorial staff of *Energies* for their kind cooperation, patience, and committed engagement.

**Conflicts of Interest:** The authors declare no conflict of interest.
