{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T22:00:01Z","timestamp":1776463201431,"version":"3.51.2"},"reference-count":48,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2013,1,17]],"date-time":"2013-01-17T00:00:00Z","timestamp":1358380800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>In the management of water distribution networks, large energy savings can be yielded by exploiting the head drop due to the network pressure control strategy, i.e., for leak reductions. Hydropower in small streams is already exploited, but technical solutions combining efficiency and economic convenience are still required. In water distribution networks, an additional design problem comes out from the necessity of ensuring a required head drop under variable operating conditions, i.e., head and discharge variations. Both a hydraulic regulation (HR)\u2014via a series-parallel hydraulic circuit- and an electrical regulation (ER)\u2014via inverter- are feasible solutions. A design procedure for the selection of a production device in a series-parallel hydraulic circuit has been recently proposed. The procedure, named VOS (Variable Operating Strategy), is based on the overall plant efficiency criteria and is applied to a water distribution network where a PAT (pump as a turbine) is used in order to produce energy. In the present paper the VOS design procedure has been extended to the electrical regulation and a comparison between HR and ER efficiency and flexibility within a water distribution network is shown: HR was found more flexible than ER and more efficient. Finally a preliminary economic study has been carried out in order to show the viability of both systems, and a shorter payback period of the electromechanical equipment was found for HR mode.<\/jats:p>","DOI":"10.3390\/en6010411","type":"journal-article","created":{"date-parts":[[2013,1,17]],"date-time":"2013-01-17T11:25:50Z","timestamp":1358421950000},"page":"411-424","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":169,"title":["PAT Design Strategy for Energy Recovery in Water Distribution Networks by Electrical Regulation"],"prefix":"10.3390","volume":"6","author":[{"given":"Armando","family":"Carravetta","sequence":"first","affiliation":[{"name":"Department of Hydraulic, Geotechnical and Environmental Engineering, Universit\u00e0 di NapoliFederico II, via Claudio, 21, Napoli 80125, Italy"}]},{"given":"Giuseppe","family":"Del Giudice","sequence":"additional","affiliation":[{"name":"Department of Hydraulic, Geotechnical and Environmental Engineering, Universit\u00e0 di NapoliFederico II, via Claudio, 21, Napoli 80125, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0471-8821","authenticated-orcid":false,"given":"Oreste","family":"Fecarotta","sequence":"additional","affiliation":[{"name":"Department of Hydraulic, Geotechnical and Environmental Engineering, Universit\u00e0 di NapoliFederico II, via Claudio, 21, Napoli 80125, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9028-9711","authenticated-orcid":false,"given":"Helena","family":"Ramos","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, Instituto Superior T\u00e9cnico, Technical University of Lisbon, Avenida Rovisco Pais, 1, Lisboa 1049-01, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2013,1,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1146","DOI":"10.1061\/(ASCE)0733-9429(1998)124:11(1146)","article-title":"Leakage reduction in water distribution systems: Optimal valve control","volume":"124","author":"Vairavamoorthy","year":"1998","journal-title":"J. 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