Effekthandel Väst — Market Data and Season Outcomes

Season-by-season and month-by-month market data for Effekthandel Väst — split out from the entity page (2026-09-05 structural review) because the data volume had grown to exceed the narrative content describing the market itself. See Effekthandel Väst for the market’s overview, platform, products, the V2G breakthrough, CheckWatt’s portfolio, and the fridges/freezers resource type.

Market outcomes

FlexAbility (2025) provides the most comprehensive historical dataset for Effekthandel Väst to date, compiled from data shared by Göteborg Energi and Mölndal Energi Elnät. (Source - FlexAbility Delrapport 2 (2025))

Activation (fria bud / ShortFlex)

Availability (LongFlex)

NODES comparison (season Nov–Mar, API retrieved 2026-10-10): LongFlex reserved volume 44.8 / 6,012.6 MWh for Göteborg (2023/24 / 2024/25) and 54.4 / 533.9 MWh for Mölndal. The 2023/24 figures match FlexAbility; the 2024/25 NODES figures are about 9% higher than FlexAbility’s DSO-supplied 5,504 and 490 MWh. The basis of the difference is not stated, so both are kept. For 2025/26 NODES gives 4,517 MWh (Göteborg) and 269 MWh (Mölndal). (Source - NODES Public Market Statistics Sweden (2026))

MaxUsage

NODES comparison (season, API retrieved 2026-10-10): MaxUsage 110.8 / 715.3 MWh for Göteborg and 8.7 / 249.1 MWh for Mölndal (2023/24 / 2024/25), in line with FlexAbility except Mölndal 2024/25 (249 vs 221 MWh). For 2025/26: Göteborg 1,101 MWh, Mölndal 281 MWh. (Source - NODES Public Market Statistics Sweden (2026))

Effektförmåga (qualified capacity)

Göteborg peaked at 19 MW registered capacity in 2023/24. The growth in Göteborg from 1 → 11 → 19 MW across three seasons tracks the FSP recruitment trajectory. As of 2024/25, Göteborg had 27 FSPs with 539 registered resources — FlexAbility singles out Effekthandel Väst as the market that has so far built the broadest base of flexibility providers, against roughly 5–10 per market at the early marketplaces. (Source - FlexAbility Delrapport 2 (2025)) The DSO Entity report (2026) cites approximately ~30 service providers for the 2025/26 season, reflecting continued growth. (Source - DSO Entity Distributed Flexibility Practices (2026))

Season totals 2024/25

• Effekthandel Väst total (Göteborg + Mölndal, all products): 7,180 MWh (vs E.ON’s 3,185 MWh across all its markets). NODES, different basis: the NODES public market statistics (retrieved 2026-10-10) give 7,759 MWh for all products in Nov 2024–Mar 2025 (LongFlex 6,546.5 + ShortFlex 248.4 + MaxUsage 964.4, each counted once). FlexAbility’s figure is DSO-supplied and kept as the headline.
• Total activated volume (Göteborg sub-market): 930 MWh — described by Göteborg Energi as more than doubled compared to the previous season (Source - Göteborg Energi Elektrifieringsrapporten nr 1 (2025)). The figure equals Göteborg’s 2024/25 ShortFlex volume (213 MWh) plus MaxUsage volume (717 MWh) in the tables above, and is about 2.4× the 2023/24 equivalent (283 + 111 = 394 MWh). The much larger 7,180 MWh figure adds the LongFlex availability volume (5,504 + 490 MWh) and Mölndal’s activation volumes (35 + 221 MWh) — i.e. procured/verified volume across all products, not activations
• Total cost estimate: ~SEK 2.9M for Effekthandel Väst (average price × volume), against ~SEK 7.5M for E.ON’s markets combined — lower prices despite higher volume (Source - FlexAbility Delrapport 2 (2025))
• Activation in 2024/25 coincided with an unusually mild winter — Sweden’s total peak demand was only 22.5 GW, an unusually low figure

Effekthandel Väst is the highest-volume Swedish flex market, and its prices are lower than E.ON’s; the cost gap is driven partly by E.ON’s Södra Skåne, which alone accounts for more than half of E.ON’s cost through 1,800 MWh of procured availability at ~2,750 SEK/MWh.

Official Ei activation counts (SGI, calendar year)

Ei’s mandatory SGI reporting (No_upreg_market indicator, EIFS 2022:5) provides an independent official count of upregulation activations by calendar year — a different lens from the season-based FlexAbility data above:

Calendar year 2024 combined (93 → 812) is nearly 9× growth. The SGI calendar year covers Jan–Mar (end of the 2023/24 season) and Oct–Dec (start of 2024/25), so the jump predominantly reflects the step-change in procurement scale that began with the 2023/24 season. (Source - Ei SGI Data 2023-2024)

Winter 2025/26 zone-level compensation comparison

The most detailed cross-market revenue data available comes from CheckWatt‘s published chart for winter 2025/26, showing compensation per 10 kWh battery system across all active zones. (Source - CheckWatt Website (2025-2026))

Two E.ON Switch zones (Kalhäll and Bromölla-Sölvesborg) had zero activations and are not shown.

Key observations:

• Effekthandel Väst revenues (357–361 SEK) were substantially lower than all E.ON Switch active zones, with Bålsta earning 7.6× more than Göteborg.
• The spread within E.ON Switch zones alone (600–2,703 SEK) reflects highly variable grid constraint intensity. Bålsta batteries were activated for 100+ hours; Göteborg/Mölndal for 2–20 hours.
• Effekthandel Väst revenues in 2025/26 were well below the ~SEK 740 net (~930 gross) per 10 kW / 10 kWh battery CheckWatt reported for 2024/25. One change from the prior season: Göteborg Energi now buys availability weekly rather than seasonally (with a stated intent to procure at least two weeks per month), while Mölndal Energi still buys for the whole season; CheckWatt describes the change but does not itself attribute the revenue drop to it.

Participation scale V2025/26

• ~1,000 battery systems from CheckWatt’s customers participated during winter 2025/26 across E.ON Switch and Effekthandel Väst combined (the source does not split the total).
• E.ON Switch (CheckWatt portfolio in January 2026): ~400 battery systems, ~8 MW.

NODES portal — 2023-2026 public data

From the NODES market dashboard (portal.nodesmarket.com/onboarding/dashboard, observed May 2026; monthly LongFlex prices and activated volumes from November 2024 onward re-checked against the exact API values retrieved 2026-10-10, see NODES public market statistics, retrieved 2026-10-10, and Source - NODES Public Market Statistics Sweden (2026)). All-Sweden view (only Effekthandel Väst markets appear as Swedish markets in NODES). Data covers months with active contracts only — summer months have no contracts and are omitted. No open reservation tenders were visible as of early May 2026.

Reserved volume (monthly, LongFlex only): MaxUsage is shown in the activated series below, so it is left out here to avoid counting it twice. NODES’ dashboard “reserved” view also includes MaxUsage, so those totals aren’t additive with activated volume.

The Dec 2024 step-change in LongFlex (from ~101 to ~1,997 MWh) marks when the 2024/25 season’s LongFlex contracts were awarded — the scale of procurement jumped dramatically. The 2025/26 season opened later (December rather than November) and with higher MaxUsage share.

LongFlex availability price (monthly volume-weighted average, SEK — NODES does not state whether the unit is per MWh or per MW/h):

Values are the exact NODES API monthly figures retrieved 2026-10-10 (”—” = no LongFlex volume that month). The May 2026 chart reading had also shown ~500 (Göteborg, Jan 2023), ~200 (Mölndal, Jan and Nov 2024) and ~275 (Mölndal, Nov 2025); the October 2026 API data has no LongFlex volume in those months. (Source - NODES Public Market Statistics Sweden (2026))

Three distinct price eras: (1) 2023 launch at ~500 SEK as a thin market; (2) 2024–2025 compression to ~200 SEK as FSP competition matured; (3) 2025/26 repricing to about 284–407 SEK as constraint intensity increased. The Mölndal premium over Göteborg appeared in December 2025 and persisted through February 2026.

Activated volume (monthly, all products, MWh):

From November 2024 onward, and for MaxUsage throughout, the figures are the exact NODES API values retrieved 2026-10-10. The ShortFlex values before November 2024 (”~”) are the May 2026 chart readings. In the October 2026 API, the monthly feed shows no ShortFlex before November 2024, while the weekly feed shows ShortFlex only in 2023 and early 2024. The two feeds don’t reconcile, so the weekly data isn’t used here. Note that the kept pre-November 2024 ShortFlex chart readings now appear only in that weekly feed, so they can’t be verified against the monthly data. FlexAbility’s DSO-supplied season data (283 MWh of Göteborg ShortFlex in 2023/24, above) confirms that those activations happened, so treat the monthly feed as incomplete for ShortFlex before 2024/25. (Source - NODES Public Market Statistics Sweden (2026))

The March 2024 ShortFlex spike (~285 MWh) is notable — a very cold late-winter month requiring repeated activations. From December 2024 onward, MaxUsage became the dominant activation product by volume, reflecting the DSO’s shift toward pre-committed consumption caps for peak management.

V2025/26 season total ≈ 1,746 MWh activated (Nov 2025–Feb 2026, per-market NODES API figures retrieved 2026-10-10; the June 2026 check gave ~1,744): Göteborg ~1,216 MWh (MaxUsage 1,101 + ShortFlex 115) and Mölndal ~530 MWh (MaxUsage 281 + ShortFlex 248). The Mölndal split matches Mölndal Energi’s own figures from the September 2026 webinar (280 MaxUsage, 248 ShortFlex). The two DSOs run the same platform differently — Göteborg’s activation is ~91% MaxUsage, while Mölndal relies far more on ShortFlex (248 vs 115 MWh, roughly half its volume). At ~1,746 MWh, Effekthandel Väst’s V2025/26 activation is on par with all of E.ON’s SWITCH markets combined (~1,400 MWh, Source - SWITCH CSV Exports V2025-26 (2026)) — the NODES market is no longer the smaller one. December 2025 was the peak month at ~700 MWh (Göteborg ~652, almost all MaxUsage).

January 2026 record — Mölndal-specific, DSO-confirmed: Mölndal Energi’s own account states January [2026] was its coldest month since joining Effekthandel Väst in 2022, driving a trading record of 118 MWh activated in that single month (mainly ShortFlex; the article does not say ShortFlex-only) — roughly half of Mölndal’s entire-season ShortFlex total above (248 MWh); the NODES API gives Mölndal 117.9 MWh of ShortFlex in January 2026, consistent with the DSO’s figure. For calendar-year context, Mölndal’s ShortFlex activation was 115 MWh for all of 2024 and only 43 MWh for all of 2025 — meaning January 2026 alone matched a full prior year and more than doubled the whole of 2025. Mölndal Energi also reviewed and adjusted its forecasting tool (prognosverktyg) this year to better time trades. (Source - Mölndal Energi Januari Rekordmånad (2026)) NODES check: the NODES API (retrieved 2026-10-10) agrees on 2025 (43.4 MWh of Mölndal ShortFlex) but shows only 7.7 MWh of Mölndal ShortFlex in calendar 2024; 115 MWh is the API’s figure for Göteborg’s 2024 ShortFlex (114.6 MWh). The article’s 2024 figure is kept as the DSO’s own statement, but it may refer to a different scope. (Source - NODES Public Market Statistics Sweden (2026))

Calendar-year totals per product (NODES API, retrieved 2026-10-10)

Both markets combined, MWh, monthly feed, from NODES public market statistics (retrieved 2026-10-10; Source - NODES Public Market Statistics Sweden (2026)). These are calendar years, not seasons, so they don’t line up with the FlexAbility season tables above.

Each product is counted once. The NODES charts show MaxUsage under both their “reserved” and “activated” views, so adding those two views together double-counts it. The data has no up/down direction field, and a true zero can’t be told apart from missing data. There is no volume from April to October in any year; 2026 has data only for January–February. Göteborg accounts for most of the volume: in 2025 it had 5,005 MWh of LongFlex against Mölndal’s 449.

ShortFlex activation price (monthly, SEK/MWh):

The early market (2023) showed Mölndal FSPs demanding ~3,500–3,600 SEK/MWh to activate, far above Göteborg’s ~2,000–2,500 SEK — likely reflecting fewer competing FSPs and/or more constrained grid conditions in Mölndal at launch. By 2024/25, markets had converged to ~2,700 SEK for both. The November 2025 Göteborg spike (~3,500 SEK) occurred in the same month GENAB had no pre-contracted LongFlex capacity, consistent with an unplanned, urgent activation.

Göteborg Energi’s own 2026/27 product page states that the average volume-weighted activation price for the whole of Effekthandel Väst in 2025/26 was about 3,500 SEK/MWh, above the ~2,700 SEK/MWh of 2024/25 shown here, and gives an illustrative availability payment of roughly 180,000–250,000 SEK for a 1 MW resource with high availability that season. Both are the DSO’s own summary figures, not NODES data, and the page gives no hours or method. (Source - Göteborg Energi Effekthandel Väst Produkter LFM (2026))