{"id":48238,"date":"2026-02-02T21:06:11","date_gmt":"2026-02-02T21:06:11","guid":{"rendered":"https:\/\/maritimehub.co.uk\/?p=48238"},"modified":"2026-02-02T21:06:12","modified_gmt":"2026-02-02T21:06:12","slug":"load-shedding-blackout-black-start","status":"publish","type":"post","link":"https:\/\/maritimehub.co.uk\/load-shedding-blackout-black-start\/","title":{"rendered":"Load Shedding, Blackout & Black Start"},"content":{"rendered":"\n

Why Recovery Time Is More Important Than Protection Accuracy

Introduction \u2014 blackouts are survivable, if recovery is fast enough<\/em><\/p>\n\n\n\n

Every ship will experience electrical faults in its lifetime. What separates incidents from disasters is not whether<\/strong> a blackout happens, but how quickly control is restored<\/strong>.<\/p>\n\n\n\n

In confined waters, seconds matter.
In open ocean, minutes matter.
In bad weather, there may be no margin at all<\/strong>.<\/p>\n\n\n\n

\n\n\n\n

What load shedding is supposed to do<\/h2>\n\n\n\n

Load shedding exists to:<\/p>\n\n\n\n

    \n
  • preserve generator stability<\/li>\n\n\n\n
  • prevent frequency collapse<\/li>\n\n\n\n
  • protect propulsion and steering<\/li>\n\n\n\n
  • avoid total blackout<\/li>\n<\/ul>\n\n\n\n

    Correct shedding:<\/p>\n\n\n\n

      \n
    • removes non-essential loads first<\/li>\n\n\n\n
    • reacts faster than generator protection<\/li>\n\n\n\n
    • stabilises voltage and frequency<\/li>\n<\/ul>\n\n\n\n

      Incorrect shedding:<\/p>\n\n\n\n

        \n
      • acts too late<\/li>\n\n\n\n
      • sheds too much<\/li>\n\n\n\n
      • destabilises PMS logic<\/li>\n\n\n\n
      • triggers cascading trips<\/li>\n<\/ul>\n\n\n\n
        \n\n\n\n

        Blackout sequence \u2014 how ships actually lose power<\/h2>\n\n\n\n

        A typical blackout chain looks like this:<\/p>\n\n\n\n

          \n
        1. Load spike (thrusters, wind, manoeuvring)<\/li>\n\n\n\n
        2. Voltage dips<\/li>\n\n\n\n
        3. Motors draw more current<\/li>\n\n\n\n
        4. Frequency drops<\/li>\n\n\n\n
        5. Protection delays activate<\/li>\n\n\n\n
        6. Generator trips<\/li>\n\n\n\n
        7. Remaining units overload<\/li>\n\n\n\n
        8. Total blackout<\/li>\n<\/ol>\n\n\n\n

          Load shedding must interrupt this chain before step 6<\/strong>.<\/p>\n\n\n\n

          \n\n\n\n

          \ud83d\udd27 Regulatory anchors (explicit)<\/h2>\n\n\n\n

          SOLAS Chapter II-1, Regulation 42<\/h3>\n\n\n\n

          Requires:<\/p>\n\n\n\n

            \n
          • continued availability of propulsion-related power<\/li>\n<\/ul>\n\n\n\n
            \n\n\n\n

            SOLAS Chapter II-1, Regulation 43<\/h3>\n\n\n\n

            Requires:<\/p>\n\n\n\n

              \n
            • emergency power availability<\/li>\n\n\n\n
            • automatic restoration<\/li>\n<\/ul>\n\n\n\n

              A blackout that cannot be recovered fast enough to maintain control is a functional failure<\/strong>, even if emergency lights come on.<\/p>\n\n\n\n

              \n\n\n\n

              \ud83d\udd3b Real-World Case: MV Dali<\/em> \u2014 Blackout With No Effective Recovery Window (2024)<\/h2>\n\n\n\n
              \"https:\/\/www.reuters.com\/resizer\/v2\/SZ3MDLSRUFK2LJ4JA3SEGHWVAI.jpg?auth=d1e723cd2bf03eeed4be0719f45f758c2906cae5418f83c464d57c1ea772d6a4\"<\/figure>\n\n\n\n
              \"https:\/\/maritime-executive.com\/media\/images\/article\/Photos\/Charts_Graphs\/Dali-timeline-NTSB.png\"<\/figure>\n\n\n\n
              \"https:\/\/i.abcnewsfe.com\/a\/23735326-3f3e-49eb-8127-0d623208d429\/Baltimore-Bridge-1-gty-jm-240514_1715702421163_hpMain.jpg\"<\/figure>\n\n\n\n

              On 26 March 2024<\/strong>, MV Dali<\/em><\/strong> suffered a blackout while departing Baltimore.<\/p>\n\n\n\n

              Key facts:<\/p>\n\n\n\n

                \n
              • blackout occurred in confined waters<\/li>\n\n\n\n
              • propulsion and steering lost<\/li>\n\n\n\n
              • emergency systems activated<\/li>\n\n\n\n
              • recovery time exceeded stopping distance<\/li>\n\n\n\n
              • collision was unavoidable<\/li>\n<\/ul>\n\n\n\n

                This incident proves a critical PMS truth:<\/p>\n\n\n\n

                \n

                Black start capability is meaningless if recovery time exceeds available manoeuvring space.<\/p>\n<\/blockquote>\n\n\n\n

                \n\n\n\n

                Black start \u2014 misunderstood and over-trusted<\/h2>\n\n\n\n

                Black start capability means:<\/p>\n\n\n\n

                  \n
                • starting generators from dead ship<\/li>\n\n\n\n
                • restoring control power<\/li>\n\n\n\n
                • re-energising essential buses<\/li>\n<\/ul>\n\n\n\n

                  It does not<\/strong> guarantee:<\/p>\n\n\n\n

                    \n
                  • propulsion before impact<\/li>\n\n\n\n
                  • steering before grounding<\/li>\n\n\n\n
                  • avoidance in confined channels<\/li>\n<\/ul>\n\n\n\n

                    ETO trap:<\/p>\n\n\n\n

                    \n

                    \u201cWe have black start, so we\u2019re safe.\u201d<\/p>\n<\/blockquote>\n\n\n\n

                    Black start is last-resort survival<\/strong>, not collision avoidance.<\/p>\n\n\n\n

                    \n\n\n\n

                    Why black start often fails in reality<\/h2>\n\n\n\n
                      \n
                    • DC control power degraded<\/li>\n\n\n\n
                    • batteries undersized or aged<\/li>\n\n\n\n
                    • start sequences too slow<\/li>\n\n\n\n
                    • human intervention required<\/li>\n\n\n\n
                    • procedures not practised<\/li>\n<\/ul>\n\n\n\n

                      Black start that works once a year on paper may fail when it matters.<\/p>\n\n\n\n

                      \n\n\n\n

                      Professional ETO mindset<\/h2>\n\n\n\n

                      Instead of asking:<\/p>\n\n\n\n

                        \n
                      • \u201cCan we black start?\u201d<\/li>\n<\/ul>\n\n\n\n

                        Ask:<\/p>\n\n\n\n

                          \n
                        • How long until propulsion is restored?<\/em><\/li>\n\n\n\n
                        • How far will the ship travel in that time?<\/em><\/li>\n\n\n\n
                        • What is the worst-case location for a blackout?<\/em><\/li>\n<\/ul>\n\n\n\n

                          Electrical recovery must be measured in distance<\/strong>, not seconds.<\/p>\n\n\n\n

                          \n\n\n\n

                          Knowledge to Carry Forward<\/h2>\n\n\n\n

                          A PMS is not a protection system \u2014 it is a time management system<\/strong>.<\/p>\n\n\n\n

                          Load shedding buys seconds.
                          Black start buys minutes.
                          Neither guarantees survival if recovery exceeds available space.<\/p>\n\n\n\n

                          The only safe blackout is the one that never fully happens<\/strong>.<\/p>\n\n\n\n

                          \n\n\n\n

                          Tags<\/h2>\n\n\n\n

                          ETO, Power Management System, Load Shedding, Blackout Recovery, Black Start, MV Dali, Marine Electrical Failure, SOLAS II-1, Ship Safety Systems<\/p>\n\n\n\n

                          <\/p>\n","protected":false},"excerpt":{"rendered":"

                          Why Recovery Time Is More Important Than Protection Accuracy Introduction \u2014 blackouts are survivable, if recovery is fast enough Every ship will experience electrical faults in its lifetime. What separates incidents from disasters is not whether a blackout happens, but how quickly control is restored. In confined waters, seconds matter.In open ocean, minutes matter.In bad […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"fifu_image_url":"","fifu_image_alt":"","c2c-post-author-ip":"","footnotes":""},"categories":[9,1],"tags":[],"class_list":["post-48238","post","type-post","status-publish","format-standard","hentry","category-electrical","category-latest"],"acf":[],"_links":{"self":[{"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/posts\/48238","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/maritimehub.co.uk\/?rest_route=%2Fwp%2Fv2%2Fcomments&post=48238"}],"version-history":[{"count":1,"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/posts\/48238\/revisions"}],"predecessor-version":[{"id":48242,"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/posts\/48238\/revisions\/48242"}],"wp:attachment":[{"href":"https:\/\/maritimehub.co.uk\/?rest_route=%2Fwp%2Fv2%2Fmedia&parent=48238"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/maritimehub.co.uk\/?rest_route=%2Fwp%2Fv2%2Fcategories&post=48238"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/maritimehub.co.uk\/?rest_route=%2Fwp%2Fv2%2Ftags&post=48238"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}