Market Aggregates

What are Market Aggregates for?

Market aggregates, especially used with weighting such as capacity weighting, are useful proxies to estimate how differences in forecasts - either between models or between different forecasts of the same model - impact energy production & consumption.

Imagine you are comparing the latest 12PM forecast of EPT against the 6 AM forecast. In Deckenpfronn, Germany, there is a huge difference in prediction for 100m wind speed. But since there is no wind park in Deckenpfronn this difference in wind speed will have no impact at the energy production at all. However, differences in wind speed at for example Reussenkoge Wind Farm, with a production capacity of over 250 MW, will have significant impacts on the energy output.

This is why we offer to compute capacity weighted averages for both solar and wind parameters. The averages are computed as

$V_{avg, weighted} =\sum_i \dfrac{C_i}{C_{tot}} \cdot V_i$

Where $V_{i}$ is the value of the variable (e.g. wind speed) at a specific location (e.g. a wind farm), $C_i$ is the production capacity at that location and $C_{tot} = \sum_i C_i$ is the total production capacity of the selected region.

Output MW Mode

By adding unit=mw to the GET /v1/forecast/market-aggregate endpoint, the query engine applies generic power curves to weather forecasts and returns predicted megawatts (MW) instead of raw weather values. This is useful for comparing different models and quick MW estimates across many European zones.

Looking for actual production forecasts? MW output here provides a model-specific forecast of potential production via power curves. For a forecast of actual production, use the Power Forecast — an end-to-end model trained on real generation data, significantly more accurate. Currently available for Germany (Solar, Wind Onshore).

MW output is only available on the GET /v1/forecast/market-aggregate endpoint, not the POST /v1/forecast/data endpoint.

MW mode:

• Activated by passing unit=mw as a query parameter on the GET endpoint

• Only works with wind_speed_at_height_level_100m or surface_downwelling_shortwave_flux_sum_1h

• Restricts geo to market_zone or country_key (no polygon or bounding box)

• Only available for zones with power-curve data (see MW-Capable Zones below)

• Weighting is auto-derived (wind → wind_capacity, solar → solar_capacity)

• Both wind and solar can be selected simultaneously; the backend issues separate queries per variable and merges

• When merge_zones_or_countries is enabled, MW values are summed across zones

Example: Wind MW Forecast

Curl

curl -X GET "https://query.jua.ai/v1/forecast/market-aggregate\
?models=ept2\
&init_time=2025-10-22T00:00:00Z\
&weighting=wind_capacity\
&market_zones=DE\
&variables=wind_speed_at_height_level_100m\
&max_prediction_timedelta=72\
&unit=mw\
&include_time=true\
&format=json" \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Accept: application/json"

Python

Response

Example: Get Available MW Zones

curl -X GET "https://query.jua.ai/v1/forecast/market-aggregate/mw-zones" \
  -H "X-API-Key: YOUR_API_KEY"

{
    "wind": ["BE", "DE", "DK-DK1", "DK-DK2", "ES", "FR", ...],
    "solar": ["BE", "DE", "DK-DK1", "DK-DK2", "ES", "FR", ...]
}

MW-Capable Zones

The list of MW-capable zones is dynamic (queried from the mw-zones endpoint based on which zones have facility data and fitted power curves).

Wind MW zones: BE, DE, DK-DK1, DK-DK2, ES, FR, IT-CNO, IT-CSO, IT-NO, IT-SAR, IT-SIC, IT-SO, NL, NO-NO1, NO-NO2, SE-SE1, SE-SE2, SE-SE3, SE-SE4

Solar MW zones: BE, DE, DK-DK1, DK-DK2, ES, FR, IT-CNO, IT-CSO, IT-NO, IT-SAR, IT-SIC, IT-SO, NL, NO-NO1, SE-SE1, SE-SE2, SE-SE3, SE-SE4

NO-NO2 has wind MW support but not solar.

MW Column Names

When MW mode is enabled, output columns are renamed:

Raw Column Name	Display Name	Unit
wind_onshore_mw	Wind Onshore MW	MW
wind_offshore_mw	Wind Offshore MW	MW
solar_mw	Solar MW	MW

Variable-to-Weighting Mapping

When not using MW mode, the weighting field is applied based on the variable:

Variable	Weighting
wind_speed_at_height_level_100m	wind_capacity
surface_downwelling_shortwave_flux_sum_1h	solar_capacity
air_temperature_at_height_level_2m	population

Aggregation Periods and Column Naming

Market aggregate responses use an avg__ prefix on variable columns:

• Hourly: avg__wind_speed_at_height_level_100m

• Daily: avg__wind_speed_at_height_level_100m, time column becomes time__to_start_of(day)

• Weekly: avg__wind_speed_at_height_level_100m, time column becomes time__to_start_of(week)

In MW mode (GET endpoint only), columns use entirely different names (see MW Column Names above).

Accessing Market Aggregates

There are two ways to access market aggregates:

• Making a request to GET https://query.jua.ai/v1/forecast/market-aggregate

• Using POST https://query.jua.ai/v1/forecast/data which allows selecting custom regions such as polygons and bounding boxes

Using the `market-aggregate` endpoint

A convenient GET endpoint that allows fast and easy access to one or multiple market zones.

The Query Engine OpenAPI docs provide an interactive description of all endpoints

Curl

curl -X GET "https://query.jua.ai/v1/forecast/market-aggregate\
?models=ept2\
&init_time=2025-10-22T00:00:00Z\
&weighting=wind_capacity\
&market_zones=DE\
&variables=wind_speed_at_height_level_100m\
&max_prediction_timedelta=72\
&include_time=true \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Accept: application/json"

Python

Javascript

Response

Using the generic `data` endpoint

While adding slightly more overhead to the query, the data endpoint provides more flexibility such as defining custom regions using polygons and bounding boxes. The example below is equivalent to the request to the market-aggregate endpoint above.

Checkout the examples on how to use market aggregates with polygons

Python

import requests

url = "https://query.jua.ai/v1/forecast/data"
headers = {
    "X-API-Key": "YOUR_API_KEY",
    "Content-Type": "application/json",
    "Accept": "application/json"
}
params = {
    "format": "json"
}
payload = {
    "models": ["ept2"],
    "geo": {
        "type": "market_zone",
        "value": ["DE"]
    },
    "variables": ["wind_speed_at_height_level_100m"],
    "init_time": "2025-10-22T00:00:00Z",
    "prediction_timedelta": {
        "start": 0,
        "end": 72
    },
    "weighting": {
        "type": "wind_capacity"
    },
    "group_by": ["model", "init_time", "prediction_timedelta", "time"],
}

response = requests.post(url, headers=headers, params=params, json=payload)
data = response.json()

Javascript

Response

Countries with Regional Zones

Some countries don't have a single zone code — use their regional zones instead:

Country	Zone Codes
Italy	IT-CNO, IT-CSO, IT-NO, IT-SAR, IT-SIC, IT-SO
Norway	NO-NO1, NO-NO2, NO-NO3, NO-NO4, NO-NO5
Sweden	SE-SE1, SE-SE2, SE-SE3, SE-SE4
Denmark	DK-DK1, DK-DK2
Japan	JP-CB, JP-CG, JP-HKD, JP-HR, JP-KN, JP-KY, JP-ON, JP-SK, JP-TH, JP-TK

Countries with single zone codes: DE, FR, GB, NL, PL, ES, BE, AT, CH, CZ, PT, GR, IE