{"docs":"https://www.nuclearnewsnetwork.com/tracker","terms":"History surfaces — append-only milestone logs, event/change feeds, and full JSON snapshots — are provided under the NNN Data License Terms (https://www.nuclearnewsnetwork.com/data-license): journalism, research, citation and AI answering are expressly permitted royalty-free with attribution; systematic bulk extraction, dataset redistribution, and embedding in commercial products or training corpora require a commercial license.","terms_url":"https://www.nuclearnewsnetwork.com/data-license","attribution":{"text":"Nuclear News Network, \"NNN Reactor Project Tracker\", https://www.nuclearnewsnetwork.com/tracker","url":"https://www.nuclearnewsnetwork.com/tracker"},"unit":{"slug":"mochovce-4","name":"Mochovce-4","plant":"Mochovce","unit":4,"country":"SK","region":"europe","reactor_type":"PWR","design":"VVER-440/V-213","capacity_mw_net":440,"is_smr":false,"vendor":"Škoda/Rosatom lineage","owner_operator":"Slovenské elektrárne","vendor_id":"org:skoda-js","owner_operator_ids":["org:slovenske-elektrarne"],"design_id":"design:vver-440","site_id":"site:mochovce","status":"commissioning","construction_start":1987,"original_cod_target":null,"current_cod_estimate":2026,"milestones":[{"date":"2026-06-16","event":"Listed as under construction in the WNA world table, grid connection estimated 2026","source":"https://world-nuclear.org/information-library/current-and-future-generation/plans-for-new-reactors-worldwide"},{"date":"2026-06-29","event":"First fuel assembly loaded into the reactor at 15:45 local time, beginning fuel load (operator announcement via WNN, 2026-06-30)","source":"https://www.world-nuclear-news.org/articles/fuel-loading-begins-at-slovakias-mochovce-4"},{"date":"2026-07-20","event":"Reactor assembly and sealing completed; unit entered physical start-up tests preceding first criticality (Slovenske elektrarne via WNN)","source":"https://www.world-nuclear-news.org/articles/mochovce-4-reactor-assembly-completed"},{"date":"2026-08-05","event":"First criticality reported (NucNet, published 2026-08-07 with 2026-08-05 dateline); single trade-press source so far - awaiting Slovenske elektrarne / IAEA PRIS confirmation","source":"https://www.nucnet.org/news/slovakia-s-mochovce-4-nuclear-power-plant-reaches-first-criticality-8-5-2026"},{"date":"2026-08-06","event":"First criticality confirmed by operator Slovenske Elektrarne (press release 2026-08-07): reactor critical at 22:10, minimum controlled power at 22:31; power ascension tests to follow","source":"https://www.seas.sk/pre-media/tlacove-spravy/slovenske-elektrarne-ozivili-reaktor-4-bloku-jadrovej-elektrarne-mochovce/"},{"date":"2026-09-21","event":"Power generation begins at 15:33 (operator via WNN); staged commissioning at 5/20/35/55/75/90% with grid synchronisation at 20%, then 144-hour full-power run before commercial operation","source":"https://www.world-nuclear-news.org/articles/power-start-up-for-mochovce-4"}],"sources":["https://world-nuclear.org/information-library/current-and-future-generation/plans-for-new-reactors-worldwide","https://www.world-nuclear-news.org/articles/fuel-loading-begins-at-slovakias-mochovce-4","https://www.world-nuclear-news.org/articles/mochovce-4-reactor-assembly-completed","https://www.nucnet.org/news/slovakia-s-mochovce-4-nuclear-power-plant-reaches-first-criticality-8-5-2026","https://www.seas.sk/pre-media/tlacove-spravy/slovenske-elektrarne-ozivili-reaktor-4-bloku-jadrovej-elektrarne-mochovce/","https://www.ans.org/news/article-8287/slovakias-newest-reactor-achieves-criticality/","https://pris.iaea.org/pris/","https://pris.iaea.org/PRIS/CountryStatistics/CountryDetails.aspx?current=SK","https://www.world-nuclear-news.org/articles/power-start-up-for-mochovce-4"],"last_verified":"2026-09-28","verified":true,"confidence":"high","notes":"Soviet-era start; completion resumed decades later - unit 3 entered service 2023. First criticality (2026-08-05/06) now confirmed by operator press release, ANS Nuclear Newswire and trade press. Power generation from 2026-09-21; grid synchronisation at 20% and 144-hour demonstration run still ahead, so commercial operation likely late 2026 to Q1 2027.","tags":["sk","vver-440"],"updated_at":"2026-09-28","slippage_years":null}}