Experimental Characterisation and Optimisation of a Steady-State Solar Simulator

Background

Solar simulators are widely used for controlled photovoltaic and solar thermal testing, but reliable measurements require well-characterised irradiance level, spatial uniformity, spectral distribution, and temporal stability. KTH operates a high-power steady-state solar simulator used for PV laboratory experiments and research. The system is capable of irradiance levels significantly above one sun, which creates both opportunities and practical challenges. Previous operation has required attenuation and dimming to reach suitable test conditions, highlighting the need for systematic characterisation, calibration, and improvement of the simulator. A better understanding of the simulator performance would improve measurement accuracy, repeatability, and usability for both teaching and research.

Aim

The thesis aims to experimentally characterise and calibrate KTH’s steady-state solar simulator and to develop practical improvements for achieving controlled, uniform, and repeatable PV test conditions. The work may also contribute to future scientific or engineering-education publications.

Specific Objectives

• Evaluate methods for reducing and controlling irradiance, including optical attenuation, lamp power control, and alternative filtering approaches.

• Characterise irradiance level, spatial uniformity, temporal stability, and spectral distribution over the PV test area.

• Develop and validate calibration procedures using reference cells, irradiance sensors, and PV devices.

• Investigate spectral mismatch and its influence on measured PV performance.

• Propose and experimentally validate improvements to simulator operation, calibration, and measurement procedures.

Methodology

The project will use KTH’s existing steady-state solar simulator together with calibrated reference cells, irradiance sensors, spectrometric measurements, and PV modules or cells.

Measurements will include spatial irradiance mapping, stability tests, spectral characterisation, reference-cell calibration, and PV I–V measurements. Different attenuation and control strategies will be experimentally compared, and an improved calibration and operating procedure will be developed.

Expected Outcomes

• Complete performance characterisation of the solar simulator.

• Calibrated procedures for irradiance and PV measurements.

• Quantification of spatial, temporal, and spectral measurement uncertainties.

• Evaluation of alternative irradiance attenuation and control methods.

• Recommendations and practical improvements for future PV laboratory and research use.

• Potential contribution to a conference or journal publication.

Deliverables

• Final MSc thesis report and oral presentation.

• Solar-simulator characterisation and calibration dataset.

• Measurement uncertainty and spectral-mismatch assessment.

• Improved calibration and operating procedures.

• Recommendations for hardware and measurement-system improvements.

Duration

The project should start in Jan-Feb 2027, with a duration of up to 6 months.

Location

KTH, Department of Energy Technology

Supervisor

Examiner