In-situ measurements are key for many sectors. In the Earth Observation (EO) domain they are of paramount importance often in conjunction with other EO data including numerical models and satellite, notably for calibration, data fusion and validation. Historically in-situ measurements mostly come from static local sensors including thermometer, anemometer, pyranometer, etc. Recently emerged via dynamic and mobile sensors in the scope of the Internet of Things (IoT) and crowdsourcing including citizen science. Whether static or dynamic, and considering any type of physical observations, they share the common concept of geo-location. Indeed, any in-situ measurements are bind with a geo-location expressed in latitude, longitude and altitude for any place on Earth. However, despite their importance, finding and accessing in-situ measurements is often difficult if not impossible. Moreover, when findable and accessible, they often lack of common standard procedures to properly identify and define their characteristics: provenance, IPR, quality / fitness for use as well as the characterization of the type and the content of the included measurements. This is often the case in the renewable energy sector and more precisely in the solar energy domain. In that context, this paper aims at showcasing a concrete example of data sharing of in-situ measurements following GEO and FAIR principles from various networks of ground-based stations providing high temporal resolution in-situ measurements in the solar domain for decades. The underlying question of data formatting and dissemination of solar resource data is one of the activities of the Task 16 of the PVPS program of the IEA .