{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T01:48:29Z","timestamp":1781747309294,"version":"3.54.5"},"reference-count":43,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,4,21]],"date-time":"2025-04-21T00:00:00Z","timestamp":1745193600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000015","name":"U.S. Department of Energy (DOE)","doi-asserted-by":"publisher","award":["DE-AC02-05CH11231"],"award-info":[{"award-number":["DE-AC02-05CH11231"]}],"id":[{"id":"10.13039\/100000015","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>Plug-in distributed energy resources (DERs), such as balcony solar, backfeed power to the home through a standard plug. These systems may represent the future of residential solar and storage, particularly as recent net metering policies have reduced the economic appeal of rooftop solar. While plug-in DERs have seen widespread success in Europe, their U.S. market is stagnant. This paper reviews the technical, interconnection, and regulatory barriers hindering the adoption of plug-in DERs. We first discuss the technical barriers, which include touch safety, breaker masking, and bidirectional ground-fault circuit interrupters. We then examine utility perspectives on plug-in DERs and strategies for navigating interconnection challenges. Finally, we discuss regulatory hurdles related to UL standards and the National Electrical Code.<\/jats:p>","DOI":"10.3390\/en18082132","type":"journal-article","created":{"date-parts":[[2025,4,21]],"date-time":"2025-04-21T20:38:26Z","timestamp":1745267906000},"page":"2132","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Barriers to Balcony Solar and Plug-In Distributed Energy Resources in the United States"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1972-0679","authenticated-orcid":false,"given":"Daniel L.","family":"Gerber","sequence":"first","affiliation":[{"name":"Lawrence Berkeley National Laboratory, Building Technologies Urban Systems Department, Berkeley, CA 94720, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-1413-1522","authenticated-orcid":false,"given":"Achim","family":"Ginsberg-Klemmt","sequence":"additional","affiliation":[{"name":"GismoPower LLC, Sarasota, FL 34239, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-1545-6452","authenticated-orcid":false,"given":"Lyn","family":"Stoler","sequence":"additional","affiliation":[{"name":"Impulse Labs, San Francisco, CA 94103, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7042-6814","authenticated-orcid":false,"given":"Jordan","family":"Shackelford","sequence":"additional","affiliation":[{"name":"Lawrence Berkeley National Laboratory, Building Technologies Urban Systems Department, Berkeley, CA 94720, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1260-2151","authenticated-orcid":false,"given":"Alan","family":"Meier","sequence":"additional","affiliation":[{"name":"Lawrence Berkeley National Laboratory, Building Technologies Urban Systems Department, Berkeley, CA 94720, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,21]]},"reference":[{"key":"ref_1","unstructured":"Wood Mackenzie (2025, March 05). 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