Cerius Radius Trefor Markedsbaseret Fleksibilitet Pilot (2025-2026)

Three linked Danish-language documents covering a joint pilot by Cerius A/S and Radius Elnet A/S (Danish DSOs, part of the Cerius-Radius group) and, in parallel, TREFOR El-net (a separate Danish DSO), to procure flexibility from customers as an alternative to grid reinforcement:

1. Primary source — a metodeanmeldelse (method notification) jointly filed by Cerius A/S and Radius Elnet A/S with Forsyningstilsynet (the Danish Utility Regulator), notifying a temporary, limited pilot methodology (14pp, ~5,700 words).
2. Radius Elnet’s own web announcement/FAQ, “Markedsbaseret fleksibilitet” (published 2025-09-19, updated 2026-03-23).
3. A press-style piece, “Nyt initiativ: Kundernes fleksibilitet kan udskyde investeringer” (published 2025-03-12), with quotes from both DSOs’ representatives.

This is the wiki’s first Danish DSO-level source — prior Danish content was limited to Energinet (TSO) in Nordic-wide contexts.

The pilot mechanism

Instead of reinforcing the grid at two main transformer stations (one in each of Cerius’s and Radius’s supply areas), the DSOs run a tender-like process (“udbudslignende proces” — below the threshold that would require a formal EU-directive procurement) to procure down-regulation flexibility:

• Two-price bid: an availability fee (one-off, paid at contract signing) plus a variable activation price (per MWh), paid only when the DSO actually calls on the resource.
• Activation: 15-minute notice, technology-neutral (EVs, heat pumps, batteries, backup generators, energy communities all eligible). Customers already on limited grid-access (BNA) terms are excluded — they can’t sell flexibility they’ve already contractually surrendered.
• Delivery-tiered payment: three flat, discrete tiers (not a smooth gradient) — 100% payment at ≥80% of contracted delivery; a flat 50% payment across the whole 50–79% delivery band; a flat 25% payment across the whole 30–49% delivery band; and zero payment plus a formal warning below 30%. Two warnings excludes a supplier from the next activation window.
• Precedent cited: Energinet’s 2019 voltage-regulation pilot tender — the closest prior Danish example of a DSO/TSO-level flexibility tender.

Two DSOs, two different models

Cerius-Radius and TREFOR El-net are each testing a distinct design, deliberately, to compare approaches:

The Cerius-Radius model is closer to a conventional dispatch-on-notice flexibility product (comparable to Swedish LFM-e/energy activation); the TREFOR El-net model is closer to a standing capacity-cap arrangement (comparable in spirit to a Swedish villkorat avtal, though structured as a paid market product rather than a curtailment-with-guaranteed-capacity split).

Legal basis

Elforsyningsloven (Danish Electricity Supply Act) §73a stk. 2 and §45b; Netvirksomhedsbekendtgørelsen (Network Undertaking Executive Order) Chapter 11, §§37, 38, 41 — requiring transparency, non-discrimination, market-based design, coordination with Energinet, and involvement of other DSOs for a temporary trial method affecting a limited user group. §73a stk. 2 already existed (introduced by an amendment to lovforslag L 87, ~2011) and was only amended (not added) by Lov nr. 1677 af 30. december 2024 — a wording change replacing “købergrupper” with “kategorier af netbrugere,” transposing the EU Electricity Market Directive; the notification’s Bilag 1 reproduces the law’s lovbemærkninger (legislative commentary), which ties the regulator’s approval authority for trial tariff/procurement methods directly to EU Electricity Market Regulation Art. 18 (tariff methodologies must incentivize flexibility use) — the same EU provision underlying Sweden’s effektavgift design requirements (see Ei’s tariff oversight).

Purpose and economics

The stated goal is to learn three things before developing standardized, sector-wide DSO flexibility products: (a) whether customers can actually deliver the needed flexibility in practice, (b) how reliable that delivery is, and (c) whether the price is competitive against the cost of grid reinforcement. Reinforcement cost comparisons use a 40-year depreciation period and 5% WACC annuity approach; incremental metering cost to support the pilot is estimated at DKK 30,000–50,000 per station.

Status and timeline

As of the notification, approval from Forsyningstilsynet was pending. An addendum dated 27 February 2026 (“tillæg af 27. februar 2026”) sets the pilot’s duration. A status update was given to the Markedssamarbejdsudvalg (MSU — a market cooperation committee involving Energinet and GPD, the Danish grid companies’ trade association) on 19 June 2025. Both DSO groups stated an ambition to run the pilots within the year the initiative was announced (2025), with the explicit understanding that this is a temporary, learning-focused methodology ahead of a permanent, industry-wide model — TREFOR El-net’s Per Sørensen and Cerius-Radius’s Cäthe Bay-Smidt both frame it as a first step toward opening a genuine Danish market for DSO-procured flexibility, not a finished product.

Relevance to the wiki

Adds a Danish comparison point to the wiki’s Swedish-focused DSO flexibility procurement material — see TSO-DSO Coordination — The Central Design Problem › EU taxonomy: four market coordination models for the cross-country comparison, and Villkorade Avtal for how the TREFOR El-net capacity-ceiling model compares structurally to Swedish conditional connection agreements. The shared EU Art. 18 EMR legal basis for tariff/procurement methodology is a useful parallel to Sweden’s effektavgift regulatory track (see Swedish DSO Tariff Reform — Three Parallel Tracks (2025–2027)).

Data gaps

• Pilot results once run (delivery rates, actual vs. reinforcement cost comparison, supplier participation)