Who do I ask for the Lastgang?

The grid operator or the metering point operator of the site's RLM meter; some suppliers pass it on too. Ask for the last 12 full months at 15 minutes, exported unchanged.

Is an MSCONS file better than a portal CSV?

It is the standard message between market parties, so its structure is defined; a portal CSV is easier to open but its layout differs by operator. Either works if it is complete and unedited.

How many values should a year have?

35,040 quarter-hours in a non-leap year and 35,136 in a leap year. In local time, the daylight saving days have 92 and 100 values; a file with 96 on every day has been padded or is in a fixed time zone.

Can I size a battery from the annual invoice alone?

Only roughly: the invoice shows the year's peak kW but not how long it lasted, and the duration decides the kWh. Use the invoice to check the Lastgang, not to replace it.

Lastgang from the grid operator: RLM data and MSCONS explained

Why the Lastgang decides a German battery case

The Leistungspreis is charged per kW of the single highest 15-minute load of the year, and the site's full-load hours (annual kWh ÷ annual peak kW) pick the price system below or above 2,500 hours (NEW Netz 2026). Both numbers come straight out of the Lastgang, and so does every peak a battery would have to cut. See German grid charges for RLM customers and the 2,500-hour rule.

MSCONS: how the values travel between market parties

MSCONS is the EDIFACT message German market parties use for metered values. The current version, AHB 3.2 / MIG 2.5, is valid from 1 October 2026; the documents are published on the BDEW market communication platform (Bundesnetzagentur Mitteilung Nr. 56).
A message carries quantities with their unit in QTY segments and the period they cover in DTM segments (corrently.io introduction). The exact qualifiers used for a Lastgang in AHB 3.2 were not verified in Zorowatt's research.
An MSCONS file is plain text that starts with EDIFACT service segments (UNA, UNB). If a client sends one, send it on unchanged: Zorowatt reads MSCONS directly.

What clients actually receive: portal exports

Most clients download a CSV or Excel file from the grid operator's or metering point operator's portal. In one user's 2021 description, Netze BW's portal offered a CSV with 15-minute values: date, time, consumption and meter reading (Home Assistant forum). Layouts of other operators were not found.
Expect a German number format (decimal comma, dot as thousands separator), dates as dd.mm.yyyy, and units given in the header as kW or kWh — or not at all.
Several meters or installations behind one transformer make the site's own load hard to isolate. One industrial owner described exactly this problem before planning peak shaving (photovoltaikforum). Ask which metering point the Leistungspreis is billed on.

Four checks before sizing on it

Count the values. A full non-leap year at 15 minutes has 365 × 96 = 35,040; a leap year 366 × 96 = 35,136.
Look at the daylight saving days: in local time the spring day has 92 quarter-hours and the autumn day 100. A file padded to 96 values on those days is common; a simulation-software FAQ explains a file with four values too many by zeros added at the spring time change (Valentin forum).
Check the unit: at 15 minutes, a column in kW is four times the same column in kWh.
Compare the year's highest quarter-hour with the kW on the Leistungspreis line of the annual invoice, and the year's sum with the billed kWh.

No RLM meter?

Sites without load metering have no Lastgang to request. Smart-meter penetration in Germany is still below 10% (SolarPower Europe 2026). A temporary logger is an option for a first look: one three-phase meter model stores at least 45 days of 1-minute data and exports CSV (Shelly documentation). That is weeks, not a year, so the annual peak stays an estimate and the report must say so.

Standard load profiles are not a substitute for sizing: they average many sites and smooth away the short peaks a battery is bought to cut.

The free meter data checker reads MSCONS and German CSV exports in your browser and shows what it assumed — delimiter, decimal comma, unit, interval, start or end labels — before any sizing. Nothing is uploaded.

Frequently asked questions

Who do I ask for the Lastgang?: The grid operator or the metering point operator of the site's RLM meter; some suppliers pass it on too. Ask for the last 12 full months at 15 minutes, exported unchanged.
Is an MSCONS file better than a portal CSV?: It is the standard message between market parties, so its structure is defined; a portal CSV is easier to open but its layout differs by operator. Either works if it is complete and unedited.
How many values should a year have?: 35,040 quarter-hours in a non-leap year and 35,136 in a leap year. In local time, the daylight saving days have 92 and 100 values; a file with 96 on every day has been padded or is in a fixed time zone.
Can I size a battery from the annual invoice alone?: Only roughly: the invoice shows the year's peak kW but not how long it lasted, and the duration decides the kWh. Use the invoice to check the Lastgang, not to replace it.

Related guides

Sources

Last checked: 2026-10-30. Every figure in this guide comes from the source linked next to it, with the retrieval date Zorowatt's research recorded (28–30 October 2026), or from arithmetic shown step by step.

Stuck on something else? Ask the community.

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