EU Science Hub

European Solar Test Installation (ESTI)

The European Solar Test Installation (ESTI) is a European reference laboratory for the verification of the power and energy generation of photovoltaic devices. ESTI is located at the JRC’s Ispra site in Italy. It has been the forefront of development of standards for electrical performance of PV products since its launch in the late 1970’s.


ESTI has unique range of class AAA solar simulators for precision cell and module power measurements, as well as outdoor testing facilities.

Traceability of Measurements to Primary Standards

To have legal validity, measurements need to have an unbroken traceability chain to international primary standards and a calculation of uncertainty.  For PV devices the most important and difficult aspect is the irradiance determination, for which ESTI is accredited for three methods.


ESTI's maintains an ISO-17025 compliant laboratory management system and is accredited for the calibration of photovoltaic devices (LAT 225) by the Italian accreditation body ACCREDIA


  • Free-of-charge calibration of reference devices for national laboratories and verification on request of technologies developed in EU programmes
  • Collaborative research with industrial partners on new materials and/or concepts to promote European competitiveness and improved standards. 
  • Funded R&D in shared-cost European programmes
  • Commercial calibration service for external customers, focusing on new technologies and respecting subsidiarity principles.
For the calibration price list or information on services please contact:

Large Scale Facade

In 1994 an amorphous silicon array was installed on the façade of the ELSA building housing the European Laboratory for Structural Assessment. At the time it was the largest façade installation in the world using amorphous silicon technology.

ESTI Meteo On-Line

Comprehensive metrological solar resource data is essential for evaluating the results of ESTI's outdoor exposure testing on PV modules.