Highlights Operational measurement data from a commercial solar process heat plant using parabolic trough (PTC) collectors, provided by the data owner and plant operator Soliterm Group. The dataset covers the period September 2021 to September 2022 with hourly timestamps, with the winter months (November to March) excluded. The collector array uses single-axis tracked Soliterm PTC 1800 parabolic trough collectors with a total aperture area of 3,087 m², using water as heat transfer fluid. The plant includes an absorption chiller powered by the solar field; the dataset therefore contains both solar thermal power output and cooling power. The dataset originates from a real commercial-scale industrial application, representative of high-temperature solar process heat systems. Plant and collector field description The data is from a parabolic trough collector array located at a solar process heat plant in Izmir, Turkey. The collector field has a total aperture area of 3,087 m² and uses Soliterm PTC 1800 collectors, single-axis tracked parabolic trough collectors with a gross area of 9.13 m² per unit, certified with a Solar Keymark datasheet (license SK0805570, issued 2022-01-12). Key collector performance parameters and tracking information are provided in the included JSON metadata file. The collectors are mounted on single-axis trackers oriented south (axis azimuth 180°) with a horizontal rotation axis (axis tilt 0°). The heat transfer fluid is water. Data files data_edited.csv Time-series measurement data with hourly timestamps. Data channels include direct normal irradiance (DNI), solar field inlet and outlet temperatures, pump flow rate, solar field thermal power output, and cooling power. Izmir__parameters.json Domain-specific metadata file in both human- and machine-readable format. Contains information about data owner, plant designer and operator, as well as plant location, collector field configuration, thermal and optical collector performance parameters, and data channel descriptions with physical units. Unit strings are parsable by the Python pint package. This file provides all information required to interpret and analyse the time-series CSV data. Photo.jpg High-resolution photograph showing a view of the collector field. P&I_Final-Model.jpg High-resolution P&ID (piping and instrumentation diagram) of the plant. Acknowledgment This dataset is published as part of DIGISOLAR Deliverable D1.4 ("Long-term monitoring data for performance verification and FDD data preparation"). DIGISOLAR has received funding from the European Union's Horizon Research and Innovation programme under Grant Agreement number 101235027 — DIGISOLAR — HORIZON-CL5-2024-D3-02. Data owner Soliterm Group