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Non-Discrimination Access Tariff

Access rule — instantiates Bottleneck Power Governance

Requires the bottleneck controller to serve every qualifying user off one published schedule of prices and terms, so access can't be rationed through secret deals or worse terms for rivals.

A Non-Discrimination Access Tariff forces whoever controls the chokepoint to publish a single schedule — posted prices, standard contract terms, service conditions — and then serve every qualifying user off that schedule, on the same conditions, with departures allowed only for reasons written into the tariff itself. Its defining move, and what separates it from its siblings, is that it governs the terms of access rather than the fact or the level of it: it does not decide whether access is owed at all, and it does not judge whether the posted price is too high; it fixes that whatever terms exist are transparent and identical across users, so the controller can't quietly favour an ally with a sweetheart rate or bury a rival in non-standard conditions. Uniformity, made public and filed, is the whole instrument.

Example

A regional electric grid is owned by a company that also owns power plants. Independent generators must move their electricity across those same lines to reach customers — the transmission network is the chokepoint, and the owner is also a competitor on it. Left to private negotiation, the owner can quote its own plants a low wheeling charge and hand rivals a higher one, or offer them awkward, one-off interconnection terms that stall for months.

Under a non-discrimination access tariff — the pattern behind FERC's pro forma Open Access Transmission Tariff — the owner instead files one public schedule: posted transmission rates, standardized interconnection terms, and a first-come queue with published rules. When an independent solar developer requests service, it pays the same posted rate as the owner's own generation and takes its place in the same visible queue; if power has to be curtailed on a constrained line, the tariff's published priority rules decide whose flows are cut, not a phone call. The comparison a regulator can now make is simple: is the developer being offered terms no worse than the owner gives itself?

How it works

  • File one schedule. Prices, service classes, and standard terms are written down, filed with an overseer, and posted where every user can see them.
  • Serve off the schedule. Every qualifying request is met on the posted terms; individualized side deals are the exception the tariff must justify, not the norm.
  • Bind deviations to written criteria. Any departure — a discount, a priority, a refusal of a specific term — must cite a reason already in the tariff, so discretion is reviewable rather than personal.
  • Anchor to a comparability standard. The controller must offer others terms no less favourable than it offers itself or its affiliates, which is what turns "same posted price" into genuine non-discrimination.

Tuning parameters

  • Schedule granularity — one flat rate versus many service classes. Finer classes fit heterogeneous users but multiply the seams where a class can be gerrymandered to fit only the incumbent's own profile.
  • Deviation latitude — how much room the tariff leaves for individualized terms. Tight latitude blocks favouritism but can force ill-fitting one-size terms on unusual users.
  • Comparability benchmark — whether "non-discriminatory" is measured against other customers only, or against what the controller gives its own downstream arm. The self-comparison benchmark is far stronger and far more contested.
  • Transparency depth — posting prices only, versus posting the queue, the utilization, and the deviation log. More disclosure makes discrimination detectable but exposes commercially sensitive data.

When it helps, and when it misleads

Its strength is precise: where access is already owed but the controller games the terms, a filed uniform schedule converts a paper right into equal, usable participation and gives an overseer a clean before/after comparison. It is cheap relative to breaking a firm up, and it leaves the controller intact.

Its central failure mode is facially-neutral discrimination — a tariff that is uniform on paper but engineered around the incumbent's own operating profile, so the posted terms are technically open to all yet practically meetable by only one. It also cannot touch the two things outside its remit: an access price that is uniform but extortionate (that is the rate review's job) or a flat refusal to serve at all (the access mandate's). And it is routinely run backwards — a controller drafts the "non-discriminatory" classes it already knows favour itself, then points to the filed tariff as proof of fairness. The discipline that keeps it honest is the comparability standard applied to effective rather than nominal terms,[1] plus monitoring of who actually clears the queue.

How it implements the components

  • non_discrimination_and_self_preferencing_rule — the tariff is this rule made concrete for external users: one posted price, one set of terms, no better deal for the controller's friends.
  • price_quality_and_service_constraint — the filed schedule is the constraint on price, quality, and service conditions, published rather than negotiated case by case.

It does not establish whether access must be granted in the first place — that duty is set by Open Access Mandate — nor cap the price against cost, which Price-Cap or Rate Review does; and it only states the anti-discrimination norm, leaving the internal separation that stops the controller favouring its own arm to Self-Preferencing Firewall.

Notes

A tariff assumes the access duty already exists; it is a way of administering access fairly, not of creating it. Pair it with a mandate (which opens the door) and, where the controller competes downstream, a firewall (which stops discrimination the tariff's paper uniformity can hide). Alone, it is strongest against crude favouritism and weakest against sophisticated, profile-shaped exclusion.

References

[1] The "comparability" principle — a bottleneck owner must offer others service comparable to what it provides itself — is the operative test in open-access transmission regulation (e.g. FERC's pro forma Open Access Transmission Tariff). It is what prevents a nominally uniform tariff from becoming self-preferencing in effect. ↩