Which electricity generation data is shown here?
How does electricity fed into the grid change on a sunny weekday, and how does a windy day compare? The chart uses the published SMARD series for photovoltaics and onshore and offshore wind energy. It shows generation data for Germany over the selected period. ‘Total wind’ is the sum of onshore and offshore wind. The two component series can also be selected separately. The lines are neither a forecast for the next day nor a measure of the installations' rated capacity.
According to the SMARD definition of net values, generation data includes feed-ins to the public grid. Electricity generated and consumed on site by a business without being fed into the grid is therefore not fully represented. The curve should not be interpreted as a measurement of every German solar installation.
Distinguish between energy quantity and average power
The data sources used contain energy quantities in megawatt-hours (MWh) per quarter hour. For the graphs, OPTUM divides this quantity by 0.25 hours to obtain the average power in megawatts (MW). For example, 250 MWh within a quarter hour corresponds to an average of 1,000 MW. This is a conversion example, not a current measurement. A daily view shows quarter-hours; longer periods show daily average power. This compression smooths out variations within a day. Therefore, for a specific daily profile, explicitly select the daily view.
All times are given in German local time, technically designated as Europe/Berlin. A standard day has 96 quarter hours, the day the clocks are switched to summer time has 92, and the day they are switched back has 100. The calculation is based on the actual intervals belonging to each calendar day. The table displays the same formatted values even if you hide individual lines. For an initial comparison, it is best to display only "Total Wind" and "Photovoltaics." Adding the total wind value to the two wind subseries would count the same feed-in twice.
A trend shows differences, but no explanation yet.
First, compare individual days and then a longer period. Sun position, cloud cover, and wind conditions can all influence generation. Plant availability and other factors also play a role. The visible curve alone cannot reveal the exact cause of every fluctuation. Furthermore, a single day is not representative of a typical year. Even a daily average of, for example, 20,000 MW does not mean that this power was available unchanged throughout the entire day.
The data also does not show what proportion of your business's electricity consumption was supplied by these installations at the same time. A green electricity contract and its supporting evidence concern a different question. The article on guarantees of origin and PPAs explains that contractual aspect. National generation and the source of an individual business's electricity should be clearly distinguished.
| Question within the company | Contribution of public data |
|---|---|
| Why think in terms of time? | The graphs show how different wind and solar power generation can be over the course of a day. |
| Can we shift electrical loads? | This needs to be checked by the company itself. The national curve does not demonstrate individual flexibility. |
| Which contract is the right one? | This view lacks, among other things, your load profile, specific offers, and your risk limits. |
What companies can take away from this
Use an unusual pattern to ask a concrete question: does our business consume a lot of electricity in these time windows, and can we change that? You need your load profile to answer it. Procurement decisions also require contract terms and an assessment of the cost fluctuations your business can bear. A visibly high solar value does not prove a low total supply price. The spot-market view complements the published price history; it too does not replace a specific offer.
If you can shift consumption over time, first identify the operational limits. Product quality, staffing plans or fixed departure times can matter more than a single market hour. Whether dynamic electricity procurement is suitable depends on this overall picture.
Data currency and gaps matter
This display is designed to retrieve data every three hours. Whether a retrieval was successful and up to which point the series are available together can be seen in the displayed data status. In case of a retrieval error, the last successful status is retained with a notification. OPTUM does not fill missing source values with zeros or its own estimates. Daily averages only appear if the required data series are complete. Therefore, incomplete days may show gaps.
Source: Bundesnetzagentur | SMARD.de, used under CC BY 4.0. OPTUM converts units and calculates the described averages. Subsequent corrections to the source may change previously published values.
Do you want to clarify the significance of different market phases for your own energy procurement? Discuss your consumption profile with OPTUM. The starting point is your available load profiles and contract targets.
