The same star will not stop them all at once.

Make the huge system huger

Call it cybersecurity, and the worst move is to harden one enormous system and hope the problem goes away. Thicken the path. Put the same star on every box. More sites can be reached. Machines that passed the same gate fail the same way. One fault is copied onto the next plant.

If plants stand apart, decide on site, and are not locked to their neighbors, an intrusion ends there. If the plant still stops when communications fail, there is no hand left that can move the herd from far away. Force spent on a simultaneous move that this arrangement already makes impossible buys one thing: a thinner choice of equipment, and a gate that exists only in Japan. Safety does not grow.

The engineering is already set out in connect widely, without controlling widely. The star requirement does the opposite. It pulls every unit inside one certification, and connects only those that got in.

What is about to become binding text

The energy agency says the general transmission operators will amend their interconnection technical requirements within fiscal 2026. From the contract application onward, IP-connected equipment on solar, storage, wind, and fuel cells would have to be a JC-STAR ★1 product. The clock starts on the day the contract application is accepted, not on the day a connection study is finished.

Sources: the agency's page on cybersecurity in the electricity sector, and OCCTO grid-code papers from meeting 20 and meeting 21. Meeting 20 does not justify the solar and storage mandate by a measured threat. It says manufacturers, when asked, expected to be able to supply compliant units around April 2027. The gate is there because the supply of labeled boxes was said to be ready.

Meeting 21 does not exempt wind from the star. It limits the first mandatory scope to the firewall on the gateway, or an equivalent defense, because labeled units for that point could be supplied by April 2027. Other wind equipment is asked to obtain the label as soon as possible, with scope and date still to be discussed. The paper does not say solar inverters are more dangerous than wind plants. It says the labeled products for the chosen scope can be ready. Fuel cells are dated April 2028 for the same reason: development, third-party checks, and the label were said to need that long.

Plants already connected are not pulled back under the new text. From April 2027, replacing an IP-connected unit is, as a rule, a replacement that needs ★1. The energy agency describes a narrow exception: if compatibility would force a wide replacement of other equipment, a plan filed with the local transmission operator can allow a like-for-like unlabeled unit for the time being. A spare in the warehouse is not, by itself, enough.

The star does not prove the plant is safe

In replies to public questions, IPA said ★1 is not a power-sector standard, the review covers the product alone, and boundary defense is outside the review. The correspondence is set out here. The label does not say this unit can be installed and operated safely on this site.

Put that label at the door of the grid, and the star decides whether a project connects. A voluntary mark becomes a permit that can stop a business. Nikkei has reported that major Chinese brands, including Huawei, Sungrow, BYD, and CATL, had zero ★1 labels under their own names, and that people in the industry said applications were being turned away — a de facto exclusion (Nikkei). The same self-declaration form does not produce the same result.

Those machines are not dropped because they fail an engineering test of grid behavior. They are dropped because a Japanese label is missing. Developers, installers, and maintenance firms in Japan then live with the price, lead time, and spare parts of whoever remains. Japanese manufacturers pay to keep a gate that the rest of the world does not use. A closed specification does not make an export industry stronger.

Washington and Beijing rewrite this every two months. The inverter stays

On 23 September 2026, US Treasury Secretary Scott Bessent said the US–China truce on tariffs and rare earths would run until 10 January 2027. Xi Jinping was in Washington that week. The one-year truce reached in Busan last October had been due to end on 10 November. Bessent also said he did not know whether a larger deal could be done. Reporting did not show Beijing immediately confirming the 10 January date.

Sources: CNBC, Politico, Nikkei Asia. Farm purchases and rare-earth magnet exports are both described as short of what the truce asked for. The talks put some nonsensitive goods outside future tariffs, and leave the rest open. The technology fight is still on the table.

A truce is built to be extended, to lapse, or to change its terms. Inverters and batteries are bolted down for a decade or more while that happens. If grid connection depends on a Japanese star, a softer negotiation in January does not put the machine back on the bid list. A harder negotiation does not make the plant safer either: the star does not look at the boundary.

When the United States actually stops a supplier, it writes the name on a list, and the same authority can take it off. A star welded into the connection rule stays after the politics move, unless someone reopens the grid code. There is no reason for Japan's power system to freeze a twenty-year gate while Washington and Beijing are still bargaining in two-month pieces.

The sentence to put back

Write this into the amendment. No company names. No country names.

Control equipment that uses IP communications must be unreachable from outside at the control point, and must still stop on the safe side, locally, if communications fail. Conformity is judged from the installation. Holding a particular domestic label is not a condition of grid connection. Replacing equipment of the same function on an existing plant does not require the new label.

Wind already stops traffic at the entrance. Apply that to solar and storage. Companies that want JC-STAR can keep it as a voluntary mark. Separate it from the right to connect. The duties inside the installation are set out in the duty-of-care proposal.

Send that sentence to the officials amending the technical requirements, to the OCCTO grid-code committee, and to the transmission operators rewriting their access rules. April 2027 is the day the rule starts to bite. Putting it back before the text hardens is the short path. After that, the argument does not retire.

After the text hardens, attach the same sentence

The interconnection technical requirements are not a statute passed by the Diet. They are rules written by the transmission operators. They can be amended again. The day the sentence goes in is not the end. It is the day refusal letters start to name a plant, a machine, and a missing star.

When that letter arrives, send it back with IPA’s own words: ★1 was not written for power systems or grid codes; a label on a PCS covers that PCS alone; JC-STAR does not use boundary defense when it decides what to assess. Add that wind’s first mandatory slice was the point where the plant meets the outside network, because supply of that labeled device was said to be ready, not because wind was judged safer. Those facts do not expire on the amendment date. The letter itself shows whether the machine was refused for how it behaves on the grid, or because the star was missing.

The reply can stay this short, every time.

If the control point is unreachable from outside, and the plant still stops on the safe side when communications fail, do not refuse connection or replacement for lack of a star. If you refuse, write down which behavior of this machine is dangerous to the grid.

One letter will not move the rule. The same sentence, stacked on every refused plant, wears out the explanation that a star is a condition of connection. Before the amendment, keep that sentence out of the text. After it, attach this one to every refusal. Both are the same demand: put the rule back on ordinary engineering.

Suomi Masuda, I-S3. Based on public documents. Not advice on a particular contract or case.