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Research on low-cost 'PV-System-Checker-Device' for future application in individual PV-System monitoring



This proposal is to identify the lowest-cost, commercially-available instruments for solar irradiation measurement, data acquisition and display, and remote monitoring. The study shall investigate their suitability for long-term measurements of PV-system performance, and lead to a design for a new device.
A major problem in the assessment of individual, widely-spread PV systems, is the determination of the amount of solar irradiation available at a specific site. Only expensive irradiation measuring equipment can give this figure exactly. Usually it is roughly estimated on the basis of decade-long irradiation measurements.
This affects the assessment of PV systems, where the ratio between the PV system output (kWh fed to the load) and the energy input (sunlight available at the site) determines the overall system performance, efficiency, and reliability.

Technical Approach

The main task is to investigate the possibilities of using commercial opto-electronic devices as low-cost solar irradiation sensors. For this, an outdoor measurement site will be established to measure and evaluate different devices.

The key points of the work to be performed are:
- Test and monitor a number of opto-electronic devices, together with different module types (i.e. amorphous and crystalline silicon cells), and well established reference devices (ESTI- Sensor, Solarimeter, amorphous and crystalline Si-modules)
- Compare data and evaluate the influence of different weather conditions on the spectral behaviour of the different devices, and select the optoelectronic devices best suited to irradiation measurement applications
- Investigate durability, protection against the environment and expected lifetime of these devices. Identify technical improvements for increased operating lifetime and stability.

This project shall identify the lowest-cost irradiation and kWh metering devices. Ideally this shall lead to universal application of monitoring to PV systems. Monitoring systems permit precise estimations of total power generated, and highlight the onset of mal-functions. An early indication of a mal-function can minimise the power lost through prolonged operation of a faulty system. Thorough exploitation of a system's potential reduces its pay-back time. A reliable and simple indicator of system operating status shall also increase confidence in PV as an energy source, assisting its diffusion.

Expected Achievements and Exploitation

The goal is to identify suitable opto-electronic devices and related data acquisition and display configurations for low-cost, long-term, accurate solar irradiation measurement in order to develop a prototype for a commercially available solar irradiation sensor with a cost below 100 ECU.

Funding Scheme

CSC - Cost-sharing contracts


Heidenhofstrasse 2
79110 Freiburg (In Breisgau)

Participants (2)

Alpha Real AG
8008 Zürich
Commission of the European Communities

21020 Ispra - Varese