Topic title: Understanding and reducing the effect of soiling of PV-modules
Close to 2% of the world;s electricity needs are provided by photovoltaics (PV) and this share is projected to exponentially increase in the coming years. Inevitably, as PV deployment increases at such rate, PV stakeholders and grid operators strive for accurate predictions of PV energy yield and investment returns. Currently PV modules and module materials are compared on the market based on their performance at standard testing conditions (STC) and their capacity to pass standardized accelerated tests.
None of the listed assessment methods can warrant high energy yield and durability on the field as recognized by both technical experts and financial investors. While the PV module manufacturers need to provide a reliability warranty for 20-30 years, and financial investors are equally planning on this timescale to realize a return on investment. Facing these demands, players in the downstream adapted a rather conservative attitude towards novel materials and technologies and they impose several years of outdoor testing. This forms a major barrier and delay for the implementation of innovations.
It is also to be expected that we will see in the coming years different applications from PV arising, ranging from large-scale PV power plants in desert regions with high insolation to customized applications of PV in an urban context like building-integrated PV. Common to all these different application fields is to understand how soiling influences the energy yield over time. It is clear that this will be pretty different depending on the local conditions (type of particles, wind impact, orientation and inclination of the PV-modules, distance between the PV-modules, height of the PV-modules, bifaciality, ...). Studies exist describing the build-up of soiling layers over time in (mostly dry) conditions, but the other aspects remained largely uncovered. It is clear that in an urban context the type, size and adhesion properties of the particles causing soiling will be different from the typical soiling layers in desert reions.
The urgency to have improved insight in the soiling process and its effect on design and integration of PV-systems is further enhanced by the appearance of innovative PV-module technologies influencing the behaviour of the front cover relative to soiling such as anti-reflective coatings, roughening of the surface to improve light coupling into the module, superhydrophobic coatings, ...
In this PhD topic, we want to focus on these aspects left largely uncovered in the past. The first aim is to improve the models of soiling and its effect over time, including the intra-module thermal effects. For this purpose we have access to several test sites including a windtunnel to study wind effects on soiling. These models will be integrated in the energy yield simulation frame developed by imec over the last 5 years. This energy yield simulation frame has been shown to have higher accuracy in comparison to other approaches (mostly black box) thanks to its capability of combining electrical, optical and thermal effects (including transients) in a bottom-up physical description of the occurring phenomena. In a next step this is used then to support and optimize the design of PV-systems ranging from large-scale PV power plants to highly specific instantiations like integration in buildings. In this way validated techno-scientific support can be given to engineering companies in the energy sector and increased confidence in the energy yield of the proposed solutions to reduce the effect of soiling will improve the "bankability" of technical and design solutions.
The core activities of this PhD topic will take place in Energyville Campus in Genk.
Required background: Master of Science and Engineering
Type of work: 65% modellling/simulation, 25% experimental, 10% literature
Supervisor: Jef Poortmans
Daily advisor: Eszter Voroshazi
The reference code for this position is 1812-74. Mention this reference code on your application form.