---
id: VOLT-HOME-WP-025
title: "Is interruptible EV charging worth more than one continuous block?"
slug: is-interruptible-ev-charging-worth-more-than-one-continuous-block
description: "A paired wholesale scenario comparison of interruptible EV charging and the cheapest continuous charging block."
published: 2026-08-30
cluster: "Smart EV charging"
status: measured
evidence_url: /research-data/home-papers/is-interruptible-ev-charging-worth-more-than-one-continuous-block.json
figure_url: /research-media/home-papers/is-interruptible-ev-charging-worth-more-than-one-continuous-block.webp
figure_alt: "Chart for Is interruptible EV charging worth more than one continuous block?: continuous-block wholesale premium over interruptible charging, shown as P10, Median, P90."
source_ids:
  - nature-v1g-v2g-2026
  - applied-energy-smart-charging
  - acer-retail-2025
  - iea-demand-flexibility
  - ec-sdac-15m
peer_reviewed: false
---

## Abstract

Some chargers can pause and resume, while a simpler controller may require one continuous block. This paper compares the optimized wholesale scenario cost of those two feasible sets for an 18 kWh event at 7.4 kW. The declared scenario assumes wholesale energy only, perfect charger efficiency, and local availability from 17:00 to 07:00. Across 3,338 paired observations, the mean continuous-block premium over interruptible charging is a wholesale scenario value of €0.026779538645895776 per event. The regenerated evidence reports no interval for this estimand. Interruptibility cannot be worse in this optimizer because it includes every continuous schedule plus schedules with pauses. The measured difference is nevertheless a model output, not a retail or device-payback estimate. It does not include communication reliability, minimum run time, switching wear, charger losses, or behavioral constraints.

## Plain-language answer

Under the frozen price curves, allowing the charger to pause is worth more than forcing the same 18 kWh into one continuous block. The mean difference is €0.026779538645895776 per event as a wholesale scenario value. No uncertainty interval is reported for this estimand.

The reason is flexibility, not lower energy use. Both schedules deliver the same requirement. The interruptible optimizer can select cheap intervals separated by expensive ones. The continuous optimizer must accept every interval between its start and finish. When cheap intervals are adjacent, both can choose the same block and the premium can disappear. When cheap intervals are separated, pauses can help.

This does not establish that frequent switching is desirable for every device. The evidence models price allocation only and assumes perfect efficiency. Operational costs and constraints could reduce the usable difference.

## Research question

The question is: how much additional wholesale scenario cost is imposed by requiring an EV’s optimized 18 kWh charge to occur in one continuous block rather than allowing the same event to use non-contiguous intervals?

The comparison isolates schedule topology. Energy, power, interval prices, and efficiency are unchanged. “Interruptible” means the optimizer may rank intervals by price and use separated intervals. “Continuous” means it examines chronological start positions and finds the cheapest consecutive sequence long enough to deliver the event.

The paper does not ask whether a specific charger supports pause-and-resume commands or whether switching affects battery health. It measures the wholesale scenario premium of the constraint in the frozen algorithm.

## Data and provenance

The source contract lists `day_ahead_prices`, `forecasts`, `forecast_accuracy`, `generation_mix`, and `zones`. Price intervals are the direct input; no device logs or household telemetry are used.

The evidence declares daily prices from 2021-01-01 through 2026-08-29, detailed intervals from 2025-10-01 through 2026-08-29, and long history from 2015-01-01 through 2026-08-29. The cutoff is 2026-08-30T00:00:00Z. The transaction was read-only with a 180-second statement timeout.

Snapshot SHA-256 is `7e97489fc8528c8cc8c38830e05b48d949ce1f67b98575dff26f5d7c321e4c67`. Protocol, registry, source-registry, and code SHA-256 values are `adb36bf6b447af9f96339249b8becaefc20422499cca1977242866347a97bd4b`, `7bcb91d7476d0a69fe9fa75a5c7782f8117e0153f82f9112b7e1d307d3943717`, `07949550ac443ff673fda5c0209b99f137544f3ffecf6775f109bb9d09663bd6`, and `57c57de79cdab2b5b6d6c54c485cb5162598c5ba0b0bfe995da40d75e6c52ba9`. These hashes define the frozen analytical identity.

## Method

The interruptible solver sorts eligible intervals by price and allocates energy from cheapest upward, limiting interval energy by 7.4 kW times recorded duration. It stops when 18 kWh has been delivered and permits partial use of the final selected interval.

The continuous solver sorts intervals chronologically. From each possible start, it accumulates consecutive interval energy at 7.4 kW until the 18 kWh requirement is met, calculating wholesale scenario cost along the way. It retains the lowest-cost complete block. For every observation with both feasible solutions, the premium is continuous wholesale scenario cost minus interruptible wholesale scenario cost.

Both solvers treat recorded interval duration explicitly. A price point is not itself a quantity of deliverable energy: at fixed power, a longer interval can supply more of the 18 kWh requirement than a shorter interval. Both paths allow the final selected interval to contribute only the energy still needed. This shared treatment prevents inconsistent energy accounting from being mistaken for a value of interruption.

The continuous path is optimized over candidate starts. It is not forced to begin immediately and is not compared with a manually chosen habitual block. The interruptible path receives the broader choice: it can use a cheap interval, skip an expensive neighbor, and resume later. The metric is therefore the wholesale scenario value of non-contiguity after the strongest continuous alternative has already been found.

Both solvers use the declared 17:00–07:00 local availability window, keeping the comparison within the registered overnight scenario.

The method family is constraint-aware charging simulation with paired schedule regret and scenario sensitivity. Holm control applies within the family to inferential claims. The reported result is descriptive.

## Results

The mean continuous-block premium is €0.026779538645895776 per event across 3,338 paired observations. The JSON reports `bootstrap_95_interval: null` and no interval method for this estimand. Positive values mean the best continuous block has a higher wholesale scenario cost than the best interruptible allocation.

The result is structurally interpretable. Every continuous block is also a valid interruptible schedule, because an interruptible controller can simply choose not to pause. The interruptible feasible set additionally contains non-contiguous selections. Its minimum cannot be higher under identical price and physical assumptions.

The magnitude is an aggregate. The figure publishes P10 = 1.734723475976807e-18, median = 0.009751249999999989, and P90 = 0.07468355000000033 EUR per event. The tiny positive P10 is numerical near-zero, not a practically distinct monetary effect.

## Robustness and placebo checks

The paired same-curve comparison is the strongest control. It holds energy, charger power, recorded prices, and efficiency constant. Feasible-set nesting supplies a deterministic sign check. A negative continuous premium would indicate a solver, feasibility, or pairing defect.

The continuous solver evaluates possible starts rather than comparing interruptible charging with an arbitrary fixed block. This makes the control demanding: interruptibility must beat the cheapest continuous alternative, not a poor habitual schedule.

The evidence contains no minimum-off-time sensitivity, command-failure placebo, switching-cost stress, or device-specific validation. It also provides no adjusted significance claim. The registered Holm rule remains a guardrail for family-level inference, while this paper reports the descriptive paired result.

Equality on a curve whose cheapest required energy is already contiguous is an additional conceptual check. Both solvers should then be able to return the same wholesale scenario cost. The JSON does not report how often equality occurs, so no frequency is attached to this check. Its purpose is reproducibility: an implementation that forces a premium on every curve would violate feasible-set logic.

Nearby days in one market can share price regimes. The sample size must therefore not be treated as an equal number of independent customer experiments. Because no estimator-valid interval is reported, the paper avoids claims about precision or independent behavior.

## Limitations

Every euro amount is a wholesale scenario value. Taxes, network charges, supplier margin, losses, switching wear, equipment cost, and communication overhead are excluded. Perfect efficiency may overstate the precision of small differences.

The model assumes instantaneous, reliable interruption and resumption. Real chargers can have command latency, minimum current, session-handshake behavior, or restart failures. None is measured. A vehicle may also taper power, making elapsed duration differ from the fixed-power scenario.

The 17:00–07:00 window is a declared scenario rather than observed driver availability. The aggregate also lacks zone, season, and event-shape breakdowns.

Finally, a technically larger feasible set does not decide user preference. Continuous charging may be favored for simplicity or reliability even when its modeled wholesale scenario cost is slightly higher.

There is no non-price objective. An interruptible plan may intentionally leave gaps and therefore retain less completion margin if a later outage occurs. A continuous plan may finish earlier despite its higher wholesale scenario cost. Completion resilience and user preference are outside the optimizer.

The comparison also has perfect knowledge of recorded prices. It does not ask whether a forecast-aware controller would identify the same separated intervals. Interaction between interruption, forecast error, and schedule churn is unmeasured.

## Practical implication

Optimization studies should compare interruptible control against the best feasible continuous block, not against immediate charging alone. That reveals the incremental wholesale scenario value of pause-and-resume capability after a strong simple alternative has already been optimized.

Controller designers should make interruption capability explicit and fail safely if commands are unreliable. A schedule that depends on separated intervals can under-deliver if a restart fails. The evidence quantifies price optionality but does not quantify reliability risk.

The measured €0.026779538645895776 is not a device purchase case. It is evidence that schedule topology matters and that its incremental wholesale scenario value is modest on the frozen aggregate.

## Reproducibility

Verify ID, slug, title, measured status, assumptions, windows, primary metric, value, sample size, figure fields, and hashes against the public JSON. Match the five references exactly to the source registry.

Using snapshot `7e97489fc8528c8cc8c38830e05b48d949ce1f67b98575dff26f5d7c321e4c67` and code `57c57de79cdab2b5b6d6c54c485cb5162598c5ba0b0bfe995da40d75e6c52ba9`, solve an 18 kWh event at 7.4 kW twice for each eligible overnight price-day: cheapest price-ranked intervals and cheapest chronological continuous block. Subtract interruptible from continuous cost only when both complete.

The reproduction should yield 3,338 pairs and €0.026779538645895776 per event, with no interval reported for this estimand. Preserve missing cases and interval durations. The current evidence and figure SHA-256 hashes are `7906ee2ab7ce9302ed2ea96b9a6b2f28ef8df669c30c6931c23dbbf2fd6c1094` and `e133cab8fbc2a4576c9f93f21c2291df2ecb03fa60456a1bbe7e64333cd12e0b`.

## Disclosure

Analysis and drafting were model-assisted. Evidence, source identities, code identity, assumptions, and hashes are disclosed. This working paper is not peer reviewed.

It is not trading, investment, tariff, or purchasing advice. All monetary amounts are wholesale scenario values. No external finding has been invented or used as empirical evidence.

## References

- `nature-v1g-v2g-2026` — Nature Energy. [Coordinated planning of European charging infrastructure and energy system for optimal V1G and V2G deployment](https://doi.org/10.1038/s41560-026-02107-5). Kind: peer-reviewed.
- `applied-energy-smart-charging` — Applied Energy. [The value of smart charging at home and its impact on EV market shares](https://doi.org/10.1016/j.apenergy.2024.124997). Kind: peer-reviewed.
- `acer-retail-2025` — ACER and CEER. [Rewarding flexibility: How retail contract choice can help unlock consumer flexibility](https://www.ceer.eu/wp-content/uploads/2025/11/ACER-CEER-2025-Retail-monitoring.pdf). Kind: official.
- `iea-demand-flexibility` — International Energy Agency. [Scaling Up Demand Flexibility](https://www.iea.org/reports/scaling-up-demand-flexibility). Kind: official.
- `ec-sdac-15m` — European Commission. [EU electricity trading in the day-ahead markets becomes more dynamic](https://energy.ec.europa.eu/news/eu-electricity-trading-day-ahead-markets-becomes-more-dynamic-2025-10-01_en). Kind: official.