Summary

  • Wisconsin Electric’s Very Large Customer tariff places dedicated generation for new loads above 100 MW on a fixed 10.48%–10.98% return on equity and a fixed 57% equity ratio.
  • The tariff’s revenues and costs are excluded from ordinary rate cases and earnings sharing, while construction-period carrying costs are already being billed monthly.
  • The commercial hinge is not Oracle’s separately disclosed collateral ceiling, but the still-undisclosed resource base, selected return, load ramp and residual value of assets if demand changes.

One asterisk in WEC Energy Group’s September investor presentation contains more information about data-centre economics than its gigawatt chart. The group describes an ordinary earnings-sharing ladder for Wisconsin Electric: the utility retains the first 15 basis points above its authorised return on equity, splits the next 25 basis points equally with customers, and refunds everything earned more than 40 basis points above the authorised level. The asterisk says the arrangement does not include Very Large Customers.

That exception is the centre of the bargain. Under the tariff approved for new loads above 100 megawatts, a customer must subscribe to “Bespoke Resources” dedicated to serving its demand. WEC says those resources can include renewable generation, battery storage, gas-fired generation and power-purchase agreements. The return on equity is fixed for the term within a 10.48%–10.98% range, with the precise rate agreed with the customer. The equity ratio is fixed at 57%. The associated revenues and costs are excluded from future ordinary rate cases as well as earnings sharing.

This is a separate economic rail, not merely a surcharge. The customer is accepting a long-lived capital-recovery structure around a supply portfolio assembled for its load. Wisconsin Electric, in turn, receives a contracted financial architecture whose return does not move through the same sharing ladder that applies to its ordinary utility earnings. Regulators retain authority over the tariff and any repurposing of assets, but the disclosed commercial logic is more bilateral than the normal pooled system.

The return begins before the load is fully visible

The tariff is already producing an accounting line. In its second-quarter 2026 filing, Wisconsin Electric recorded $10.8 million of “Bespoke resources current return” for the quarter and $15.1 million for the first six months of the year. The company describes this as carrying costs incurred during construction and billed monthly to customers.

The phrase “current return” matters. A conventional public discussion of a data-centre campus tends to jump from an announced gigawatt figure to a distant picture of electricity sales. Here, part of the economic relationship operates during build-out. Capital is being committed, carrying costs are accruing and customers are being billed while dedicated resources are under construction. Future delivered megawatt-hours are not the only clock.

That does not make $15.1 million a proxy for the mature opportunity. The filing does not allocate the aggregate figure among Oracle, Microsoft, Vantage or any other customer. Nor does it disclose the asset balance to which an eventual customer-specific return will apply. The number demonstrates that the mechanism is active; it does not reveal its final scale or profitability.

The distinction is useful because WEC’s headline demand numbers are forecasts. Its September 2026 investor update projects 3.9 gigawatts of data-centre demand by 2030, comprising 2.6 gigawatts associated with Microsoft and 1.3 gigawatts associated with Vantage, OpenAI and Oracle. In the same deck, data centres accounted for only 1% of 2025 retail megawatt-hour deliveries. The gap between those two statements is the construction and ramp risk that the tariff is designed to finance and allocate.

A customer-specific capital stack

The fixed 57% equity ratio deserves at least as much attention as the ROE band. Utility returns are earned on the equity portion of an approved investment base, not on every dollar mentioned near a project. By specifying the equity share for the contract term, the VLC tariff makes capital structure part of the customer bargain. By fixing the return within a band, it also limits future ambiguity about the price of that equity layer.

But the public disclosures omit the denominator needed to estimate earnings. WEC has not disclosed, in the cited filings, the dollar value of Bespoke Resources assigned to each customer, the chosen ROE within the range, the timing of additions to the resource base or the detailed treatment of overruns. Multiplying 3.9 gigawatts by anything would be meaningless. Multiplying Oracle’s potential collateral requirement by 10.48% or 10.98% would be worse: it would combine two contracts that protect different risks.

The resource terms show why the denominator can be complex. Wind and solar resources run for 20 years. Company-owned gas generation and batteries run for their depreciable lives. A purchased-power contract runs for its own duration. A single VLC supply package can therefore contain assets and contracts with different clocks, residual values and operating exposures. The published ROE band is simple; the investment base beneath it may not be.

Two protections, two risks

Oracle’s possible $7 billion collateral requirement has already drawn attention. Wisconsin Electric says the requirement grows as project costs are incurred and is expected to peak at that amount. It is credit support: protection against a counterparty failing to honour payment or cancellation obligations. It is not cash already posted, the price of a campus, rate base, revenue, profit or the amount on which the utility earns its disclosed ROE.

The VLC tariff addresses a related but different risk. A utility could build generation and network assets around a forecast load that arrives late, arrives smaller or disappears. The tariff says a customer that terminates service or reduces its forecast demand remains responsible for dedicated resources and distribution facilities built for that forecast, measured at net book value, unless the assets can be repurposed with approval from the Public Service Commission of Wisconsin.

Credit support makes that obligation more collectable. The tariff defines the obligation. Keeping the two separate is essential to understanding who bears what. The customer carries a substantial part of stranded-cost risk; the utility and its investors retain construction, execution and regulatory exposure; the commission determines whether repurposing can transfer some residual value to a broader use.

What the earnings-sharing exclusion changes

Earnings sharing is a regulatory release valve. When a utility earns more than its authorised return, the mechanism can return part of the upside to customers without waiting for a full rate reset. Excluding VLC economics means the ordinary 15/25/40-basis-point ladder is not the right tool for judging the margin created by Bespoke Resources.

That does not automatically mean the arrangement is more profitable. A separately negotiated return can come with separately assigned costs, dedicated risks and customer protections. Construction can be delayed. Resource costs can move. A load ramp can change. A high nominal ROE can be earned on a smaller or later equity base than investors imagine. The point is narrower: the tariff draws a boundary around this stream, so consolidated utility results disclose less about how it performs than they would if everything flowed through the ordinary sharing pool.

For customers, the same boundary can be attractive. It identifies the assets and contracts required for their load rather than socialising the entire bill. It can reduce arguments about whether residential and small-business customers are subsidising a private computing campus. The Wisconsin commission’s tariff process explicitly addressed safeguards against cost shifting. Yet a ring-fence is only as strong as its allocation rules: shared transmission upgrades, common network benefits, repurposed assets and load-forecast changes all test the perimeter.

The right denominator remains private

Investors now know the return range, the equity ratio and the contract duration rules. They do not know the assigned investment base by customer. That is the missing denominator.

It should discipline both exuberance and dismissal. WEC’s 3.9-gigawatt forecast signals a very large potential power requirement, but gigawatts are not dollars of approved investment. The $15.1 million current return proves that construction-period billing has started, but six months of carrying-cost income does not establish steady-state earnings. A $7 billion peak collateral requirement indicates the scale of protected exposure, but not the value of the resources on which Wisconsin Electric earns a return.

The market should therefore watch the tariff as a contract portfolio rather than a single data-centre statistic. Each service agreement can select a point in the ROE range, attach a different mix of resources and set its own ramp. The aggregate opportunity will be the sum of those private schedules, not a percentage applied to a public headline.

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