There are four ways to buy a battery storage plant —
rights, completion, track record, and the vehicle

Over 48 hours from 30 to 31 July 2026, three disclosures appeared in Japan that could hardly have been more different in character.

The first was J-Holdings' acquisition of the Shokawa battery storage plant (provisional name) in Takayama, Gifu Prefecture. Roughly 2 MW / 8 MWh, for approximately ¥700 million. Handover is scheduled for November 2026, grid connection for December, and entry into the balancing market is planned for the first half of the following fiscal year. The second was Renova's Fukuroi-Ukuriwa plant (99.9 MW / 280 MWh) in Shizuoka: Mizuho Bank's first fully merchant project financing for battery storage, at approximately ¥7.2 billion — a disclosure about building something over the next three years. The third was JALCO Holdings' acquisition of an already-operating high-voltage grid-scale plant (2 MW / 8 MWh), announced together with an upward revision of its full-year consolidated earnings forecast. The plant had begun trading in the balancing market in May 2026 and was already generating revenue.

One company putting debt on 100 MW it will spend three years building. One paying ¥700 million for a finished asset and waiting until next fiscal year for market entry. One buying 2 MW that is already running, and raising its earnings guidance for the current period on the strength of it. Three transactions of fundamentally different natures, all living inside the same phrase: "buying a battery storage plant."

In "Why Battery Storage Plants Are Bought With Cash" we argued that security is the effect; the contract is the cause. In the follow-up, "How a Banker Reads Your Battery Storage Plant", we looked at what lenders actually test in a financial model. This third and final part of the trilogy takes the buyer's seat, and addresses two questions. Why does the same size of plant carry three different prices? And why does the "track record" you paid the top price for sometimes fail to end up in your hands?

01 — "Wait for a finished asset and buy it" is no longer the only option

"We want to buy a completed battery storage plant. Do you have anything good?" Almost every buyer enquiry we receive opens with that sentence. Yet what is actually trading in 2026 is not only finished assets. Three forces — counterparty credit, interest rates, and the seller's own position — explain how the shape of these transactions widened.

Credit — what gets underwritten is the counterparty, not the plant

A completed-asset purchase almost always involves progress payments or advances during construction. Rewritten from the buyer's side: it is a transaction in which you place several hundred million yen with the seller and the EPC contractor before you take delivery. This is where a great many deals now fail internal credit review. If the credit-agency score of the seller or the EPC does not clear the threshold a large corporate uses to approve a new counterparty, the authority to release ¥400–500 million before handover simply will not be granted. What stalls completed-asset transactions is rarely the quality of the plant; it is the credit of the person on the other side (our observation).

Buyers believe they are "looking for a good asset." But what is actually on trial at the approval table is the counterparty. Turn that around: if the seller is a subsidiary of a listed group or an operating company of real scale, the same asset at the same price gets approved. A variable that appears nowhere on the spec sheet is deciding most outcomes. That is the reality of completed-asset trading.

Interest rates — waiting now has a price tag

The Bank of Japan raised its policy rate to 1.0% in June 2026 and held it at the Monetary Policy Meeting of 31 July 2026. The 10-year JGB yield reached 2.880% on 9 July 2026. There was a time when the gap between acquisition and first revenue could be dismissed with "we can wait." Now that gap carries an explicit opportunity cost. What buyers are pricing is not only the asset but the time between acquisition and first cash in. This rate environment is the reason this column keeps returning to the idea that the track-record premium is, at bottom, a premium on time.

The seller's position — an exit other than "finish it, then sell it"

A growing number of developers secured rights early but cannot move forward, blocked by construction funding or by their own credit. Insisting on the single path of finishing before selling means holding inventory with capital tied up in it. So "sell at the rights stage" and "energise it, build a track record, then sell" have become genuine products on the market. From the seller's side there are situations where locking in profit at the rights stage is simply more capital-efficient. That calculation is what has given depth to the lower rungs of the ladder.

02 — There are four ways to buy

Set out plainly, there are four acquisition structures for a battery storage plant.

These four are not ranked. The right answer changes with the capabilities the buyer has and the risks the buyer can carry — nothing more. Start with the whole picture on one page.

All four appeared in the disclosures of a single listed company

What is striking is that all four structures surfaced inside the timely disclosures of one listed company in the space of eight months in 2026.

One company, four acquisition structures, eight months. This does not look accidental. We read it as a worked example, published in the form of regulatory disclosure, of the principle that the optimal way to buy differs by the phase the project is in.

The path from ② to ③ deserves particular attention, because it appears to have been designed in from the outset: enter at the rights stage, then move to an SPC structure as the project is developed. That design logic connects directly to "how far does a track record survive?" (§06) and "choosing the vehicle" (§07) below. An acquisition structure is not fixed at the moment of purchase; it can be moved during the holding period. Whether a buyer thinks that way makes a considerable difference to how much freedom it has.

03 — There is a ladder in the price

So what does each one cost? Here we hit the first wall.

Timely disclosures by listed companies in Japan conventionally state only that the acquisition price is "less than 30% of consolidated net assets at the end of the immediately preceding fiscal year," withholding even a range (this follows the materiality thresholds under the Tokyo Stock Exchange's timely disclosure rules). Of the summer 2026 disclosures, the only price made public was the approximately ¥700 million for the Shokawa plant (completed handover, approx. 2 MW / 8 MWh). The existence of the ladder is now evidenced by public cases, yet the size of each riser has not been disclosed to the market. A visible ladder with invisible risers. That is the state of Japan's secondary market today.

So we overlay what we have observed in brokerage and buy-side enquiry work through the first half of 2026.

The two risers are made of completely different material

Leaving this vague and simply saying "the higher the rung, the higher the price" would be sloppy. Between Tier 1 and Tier 2, physical things genuinely get added. Battery containers, PCS, the substation equipment, foundations and site works, the grid connection cost contribution — going from bare rights to a finished asset means buying and installing all of it. Calling that difference "the price of risk" would not be accurate.

Initial investment for a high-voltage 2 MW / 8 MWh class plant has been reported at roughly ¥500–600 million (T2 | Nikkei Energy Next). Set that against the ¥150–200 million observed at the rights rung, and the composition of the riser starts to come into view.

So the roughly ¥500–600 million riser between Tier 1 and Tier 2 is mostly hard cost. Buy the rights for ¥200 million and you still have to spend ¥350–450 million to turn them into a finished asset. The phrase "rights are cheap" misleads precisely because this part drops out of view. Within the Tier 1 to Tier 2 gap, the portion that can fairly be called a price for risk is only the thin layer between the ¥500–600 million of cost and the ¥700–800 million asking price — somewhere around ¥100–200 million. Read the other way, that ¥100–200 million is also the reward for selecting your own EPC, managing the schedule and seeing it through to completion.

The gap between Tier 2 and Tier 3 is a different animal entirely. Not one yen of additional equipment sits inside it. The containers, the PCS, the substation equipment are identical to the completed asset. Same land, same connection terms. And still there is a ¥100–200 million difference. The only things moving are the time to market participation and the verifiability of the financial model.

The most important thing in this chart is the gold layer at the top. Physical things explain the price up to about ¥700 million. Beyond that, no equipment and no construction corresponds to the difference. And this is also the layer where buyers most often misjudge. The next chapter takes apart the four risks that create the risers, one at a time.

04 — What the risers really are: the price of taking on risk

As broken down above, the part of the price difference that cannot be explained by physical things — the thin layer between Tier 1 and Tier 2, and the whole of the gap between Tier 2 and Tier 3 — is created by four risks and, specifically, by when each of them passes from seller to buyer. Here they are, with the defences available to a buyer.

By the time rights are saleable, one filter has already been applied

Connection study responses with indicative schedules running to several years are not unusual. But sites like that do not become saleable rights in the first place — the developer withdraws the application and that is the end of it. The "grid connection rights" that circulate in the market are only those that passed the filter of schedule, contribution and location. What the ¥150–200 million at Tier 1 buys is less the land itself than a connection slot that made it through that filter.

That does not mean grid risk disappears at the rights stage. An estimate remains an estimate, and both the final contribution and the schedule can move if the assumptions in the response (the state of the substation bank, the distribution line and so on) no longer hold. "The rights are in place" and "it will connect as planned" are two different pieces of information. Always inspect the original response, down to the date, the indicative schedule and the stated assumptions. For an operating asset, this class of uncertainty has already been resolved. That is part of what the Tier 3 price contains.

What does credit look like when you convert it into price?

Battery storage transactions lack the machinery that residential property transactions have. Housing in Japan comes with layer upon layer of institutional cover for the credit of sellers and contractors: completion guarantee schemes (which cover advances and cost overruns up to a limit if the builder fails), title registration, established practice on non-conformity liability, defect liability insurance. As at the time of writing we can identify no standard mechanism for protecting advance payments in private battery storage transactions. On performance bonds and escrow in Japanese practice, we could not even find published data on how widely they are used.

Without machinery, credit goes straight into price. In our practice we see two-track pricing on the same asset — something like ¥780 million for immediate settlement against ¥830 million for payment on delivery (our observation; a spread of roughly 6%). That difference is not a discount. It is the consideration for the seller taking the buyer's settlement risk — which is to say, the market price of credit risk up to delivery. It is the same phenomenon we described from the seller's side in "Why Battery Storage Plants Are Bought With Cash", viewed from the buyer's seat.

The payment schedule is the blueprint for risk transfer

In practice, the single most effective lever is aligning the timing of payment with the timing at which risk moves. There are several established patterns for tying money to milestones — deposit plus balance on settlement, lump-sum settlement after final connection consent, and others. Where there is doubt about the seller's credit standing, this design is what decides whether the transaction works.

Note: the table sets out common design patterns in completed-asset sales; it does not recommend particular terms. Confirm individual contract provisions with counsel.

The regulatory valley between "complete" and "earning"

The first three risks are, in effect, about construction. The fourth is different in kind. JALCO's disclosure on the Oita rights acquisitions (29 June 2026) contains a sentence that is easy to skip past: because participation in the balancing market requires coordination, testing and procedures with the aggregator and other parties after the start of power receipt, the period from energisation to actual market participation is expected normally to take approximately one to three months.

The Shokawa plant mentioned at the outset, with connection in December 2026 and balancing-market entry stated as "the first half of the following fiscal year," is allowing time to cross the same valley. Two separate companies, two disclosures, the same gap confirmed twice.

Buying an operating asset skips the valley. What the buyer gets is cash flow from day one and the disappearance of residual screening risk. On top of that, the financial model changes from an estimate into a measurement. As we saw in "How a Banker Reads Your Battery Storage Plant", what lenders dislike most is a number they cannot verify. In a development-stage project, revenue is a simulation however far you take it; in an operating project, primary data on actual cleared prices, clearing rates and availability accumulates month by month. The buyer can price after verifying measurements rather than forecasts.

05 — On 1 September 2026, the basis for pricing itself moves

A word of caution for any buyer paying a track-record premium. A track record is a number from the past. But the rules of the market that produced it are changing right now.

At the 4th Electricity Stable Supply Working Group on 14 July 2026, the Agency for Natural Resources and Energy (ANRE) put forward a proposal to cut the price cap for primary reserve, secondary reserve ① and the composite product in the balancing market from ¥15 to ¥10 per ΔkW per 30-minute block. EPRX, the balancing market exchange, states on its official price-cap page that, as a result of that deliberation, an update to the price cap has been decided, and it updated the published price-cap document on 30 July 2026. It applies from delivery on 1 September 2026; ¥15 remains in force for delivery up to 31 August. EPRX adds that the figure may change in light of the outcome of relevant future deliberations.

The stated basis for the cut was, ironically, the fact that the market is improving. Comparing before and after the shift to day-ahead trading, the shortfall rate for the composite product improved from 14.6% to 5.3%, and for primary reserve from 46.3% to 16.1% (results for 6 June to 3 July 2026). Even so, unfilled blocks remain and clearing continues to occur near the cap — hence, the logic runs, lower the cap. Given the volume of battery capacity due to connect and enter the market, it is reasonable to expect this direction to continue.

What it means for buyers — which regime produced that track record?

The conclusion is simple. The "annual revenue" of an operating asset may be a number produced under the regime that existed before 1 September. A financial model that extrapolates past clearing results straight into the future breaks on that single point. As shown in the previous chapter, the gap between Tier 2 and Tier 3 has no physical backing. That is exactly why you have to check the shelf life of the number that justifies it.

If you are buying a track record, confirm these three things without fail.

The track-record premium is itself a rational payment. But do not mistake what you are paying for. You are not paying for past cleared prices; you are paying for the fact that the regulatory valley has been crossed, and that verifiable data exists. Whether a buyer can hold that distinction is what separates good buying from bad. If you think you are paying for the former, your premise changes on 1 September. If you are paying for the latter, the case for the acquisition survives a fall in cleared prices.

Even at the bottom of the ladder, the rules are tightening

The same thing is happening at the rights rung.

• Connection study applications for grid-scale batteries surged to 9,544 in FY2024, roughly six times the previous year.
• As an anti-speculation measure, the deposit doubled from 5% to 10% of the indicative grid connection cost contribution for connection contract applications made on or after 1 April 2026. Withdraw for reasons of your own and it is subject to forfeiture.
• Further, submission of proof of land use rights for the project site will become a requirement, following amendment of the relevant rules, for applications accepted on or after 1 October 2026 (planned) — with exceptions for expansion, replacement or refurbishment of sites where a business is already operating.
• In TEPCO Power Grid's service area, a cap on the number of high-voltage and extra-high-voltage connection studies a single operator may hold simultaneously took effect on 1 August 2026.

Rights are becoming scarcer and, at the same time, closer to real demand. Mass-produced "paper rights" are being squeezed out of the market, and the value of the rights that survive should rise. For a buyer, that means the bar for buying at Tier 1 is going up, and the advantage of having bought at Tier 1 is going up with it. The design of how you buy begins at the sourcing stage.

06 — How much of that "track record" actually comes with you?

Here is the point this column most wants to make. The "track record" you paid a Tier 3 premium for may, depending on how you buy, not come with you at all.

The track record of an operating asset has to be thought of in two layers.

Note: the generation business (including battery storage) filing obligation applies to facilities above 10,000 kW. High-voltage 2 MW-class projects sit outside that framework, so the Electricity Business Act row above bites mainly where the target is extra-high-voltage.

The table says one thing. The dividing line is whether the contracting entity changes. Buy the SPC equity and qualifications, contracts and permits stay where they are. Buy the assets alone and balancing-market qualification has to be obtained again by the buyer, while subsidised assets bring an approval gate with them. The one large exception is the capacity market, where the contractual position can be succeeded to subject to OCCTO's prior consent — and where the terms expressly carry over requirement performance, that is, the regulatory "track record" itself.

The other trap — the track record is tied to the aggregator's name

There is a second point that practice tends to miss. A balancing-market track record is tied to the aggregator's registration.

In the balancing market, a trading member (typically an aggregator) obtains an operator code, registers the resource, and can trade only after passing performance verification and pre-qualification. EPRX's FAQ likewise proceeds on the basis that what passes verification and pre-qualification is "the trading member's resource," treating even proxy bidding as a delegation-consent arrangement under Article 8(6) of the Trading Rules. Three cases follow from that structure.

The consequence is intensely practical. If you buy an operating plant through a direct asset sale and also switch aggregator, balancing-market screening and record reset, and you may incur both the cost of re-screening and re-testing and a period of no revenue. Recall the disclosure quoted above: normally one to three months from energisation to market participation. You have paid a premium of ¥100–200 million with no equipment behind it, and the very thing that justified it stops. That is a step back down the ladder.

To "security is the effect, the contract is the cause," this column adds the following.

There are two ways to secure the track-record premium with certainty: (1) acquire while retaining the aggregator, or (2) acquire the SPC equity, so the registration moves untouched. Put the other way round, the design that looks most natural — buy the assets and move operations onto your own platform — is the one that destroys the track-record premium most thoroughly. We regularly meet buyers negotiating hard on price without having noticed the contradiction.

07 — Choosing the vehicle: direct asset sale, or SPC equity

Of the four ways to buy, SPC equity transfer alone is different in kind. You are not buying a thing; you are buying the vehicle around it. And the choice of vehicle bites harder the higher up the ladder you go.

In the disclosed case where a listed company took a silent-partnership interest in an SPC, the O&M, aggregator and asset-management arrangements were in fact left exactly as they were. That is a structural answer to the succession problem set out in §06. This form also allows a partial purchase — participation through a minority interest rather than a 100% acquisition — which the other structures do not.

That said, buying the vehicle means taking on what is inside it. The centre of gravity in DD moves from the asset to the entity, and the design of representations, warranties and indemnities becomes the core of the review. What you are buying is not a battery plant but a bundle of contracts wrapped around a battery plant. Start anywhere else and the conversation about price will not connect.

As set out in "Why Battery Storage Plants Are Bought With Cash", what a lender actually takes security over is this same SPC equity and bundle of contracts. Vehicle B is the one best aligned with how finance looks at the asset. The more a buyer intends to put debt on the asset at the exit, the more it is worth choosing the vehicle at the entry.

Provisions to insist on when buying SPC equity

08 — Overseas, this ladder is discussed in terms of discount rates

In Japan the risers are unpublished tacit knowledge. Overseas they are set out at the level of stated accounting policy.

Gresham House Energy Storage Fund (GRID), the UK's largest listed battery fund, discloses that it removes the discount-rate premium applied to construction-stage assets on transition into operation. As at Q1 2024, the weighted average discount rate for operational assets alone was 10.6%, roughly 20 bps below the portfolio including construction-stage assets (10.8%). The discount rate falls the moment an asset goes live, so the same expected cash flow supports a higher valuation — "operational equals risk shed equals higher price," institutionalised as policy.

The development side has the same structure. Enerdatics, which tracks European M&A data, observes that the developer premium on battery projects (the uplift on development consideration, not the asset price itself) steps up rung by rung: around US$20,000/MW at early stage, around US$50,000/MW for advanced development, and above US$80,000/MW at ready-to-build. Here too the uplift is observed separately from the price of the equipment, which is instructive when thinking about Japan's risers. (The same research reports German RTB separately at US$50,000–170,000/MW, so note that the spread between markets is wide.)

09 — The buyer's discipline: decide the rung and the vehicle, then look at price

Three prices mean three different products. If so, the first thing a buyer should settle is not "how much" but "at which rung, and which risks, can I carry on my own balance sheet?" Compare prices without settling the rung and you are measuring ¥200 million of rights against an ¥800 million operating asset — different products — with the same ruler. The buyer of the former still has ¥350–450 million of spending ahead of it.

Start by answering three questions

Risks assumed and where to look, rung by rung

Clear these 32 items before you buy

Once the acquisition structure is settled, the work becomes verification. Below are the items we actually use in buy-side advisory work, organised by structure. Tick them as you go (nothing is saved).

Three misconceptions we hear regularly

And whichever form you choose, a third-party eye is what works

Whichever of the four you pick, independent verification is the common denominator. Completion and performance (①), connection terms and permits (②), contingent liabilities and contract succession (③), degradation and the authenticity of operating data (④) — the centre of gravity in due diligence shifts with the form, but the principle does not: turn numbers you cannot verify into numbers that have been verified.

Not the seller's explanation, not the buyer's hopes, but a third-party eye brought into the transaction. We believe that is the shared infrastructure this market needs in order to reach its next stage. For the specific areas covered in technical due diligence, see also "Is That 'Approval' Real? — Technical checks before buying a grid-scale battery plant: 43 items across 9 domains".

Closing — how the trilogy ends

Part 1 asked why sellers choose cash. Part 2 asked how a banker reads your plant. This column is the other side of that: at which rung, and in which vehicle, should a buyer buy?

The same spine runs through all three. Once the hard cost has been stacked up, what finally separates one price from another is when, and from whom to whom, risk moves. Security is the effect; the contract is the cause. And:

In 2026 the ladder took shape in public cases. The day the size of each riser is disclosed to the market is still ahead. Until then, the only way to measure a riser is triangulation between primary sources, close reading of contracts, and observed practice. We provide that triangulation from a neutral position.