PARALLEL EVENTS PROGRAMME

10:30 - 11:15 Assessment of meteorological and environmental factors in hot desert climates

Hot desert regions present ideal conditions for the deployment of large-scale photovoltaic plants as they have high level of insolation and are usually not constrained by land availability, topography, and regulatory framework. However, the environmental challenges that arise in such arid climate, such as dust and high temperature, affect the performance of these plants.  As solar PV applications take the center stage in the path to net-zero emissions in these regions, there is a greater need to understand how to mitigate and address these challenges through understanding of the accuracy, completeness, and quality control in the collection of meteorological an environmental data, and a sharper focus on the use of these data to support and promote PV applications. In this session, we will discuss these requirements with reference to (a) challenges in hot desert climates, (b) the impact of high aerosol loads and low cloudiness conditions on solar resource assessment, (c) the promotion of rooftop PV application in urban areas, and (d) the predictive operation and maintenance of PV plant. Specific topics include:

• Instrumentation, measurements, and best practices for data collection and quality assurance.
• Solar Radiation modeling and forecasting specific to desert atmospheric conditions.
• Factors affecting surface irradiance such as spectral albedo, aerosol optical depth, and solar spectral distribution.
• Meteorological and environmental forecasting for predictive PV operation and maintenance.
• Monitoring, forecasting and mitigation of soiling.

Chairman:
Dr. Dunia Bachour, QEERI, Qatar
Dr. Antonio Sanfilippo, QEERI, Qatar

• Mr. Jan Remund, Meteotest AG, Bern, Switzerland
  Title: Solar resource and forecast data for hot desert climates
  Position Statement: Inputs based on the new (4th edition) solar resource handbook - which will be in a raw draft version in September.
  
  
• Dr. Daniel Astudillo, QEERI, Qatar
  Title: Solar Resource Assessment in the Qatar Desert Conditions
  Abstract: A reliable determination of the available solar resources is essential throughout all phases of solar power conversion projects, from prefeasibility to design and, during operation, monitoring of production and performance and even forecasting. Direct, in-situ measurements of solar radiation at ground level can provide the most accurate data but require constant care in the form of frequent preventive maintenance and checks in order to maintain the equipment and sensors operating as intended, and the use of sun trackers to measure direct and diffuse irradiances introduces additional complexity and thus possible points of failure. Thus, to obtain high-quality measurements, maintaining a complete station in operation is not an easy task, and becomes especially challenging in the harsh environment of desert conditions, as in the case of Qatar. The Qatar Environment and Energy Research Institute (QEERI) currently operates a network of 15 solar radiation monitoring stations across the country, with most of them at remote sites in the desert, which present constant challenges to the managing team.
  
  
• Dr. Christian Gueymard, Solar Consulting Services, USA
  Title: Dust aerosol data and their use in solar irradiance prediction
  Position Statement: Four aspects of the importance of dust aerosols are considered here: Impacts of dust aerosols on the solar source and the soiling of PV panels; Main sources of aerosol data and their pros and cons; How do aerosols in general (and dust aerosols in particular) impact the modeled solar irradiance components and modeled solar resource databases used for the design and financing of PV projects?; Forecasting resources for the efficient grid integration of PV production and the optimized scheduling of cleaning operations.
  
  
• Dr. Manajit Sengupta, NREL, USA
  Title: Accuracy of solar resource using satellites under desert conditions
  
  
• Dr. Ana Maria Gracia-Amillo, FUNDACION CENER, Sarriguren, Spain
  Title: Specific considerations when simulating PV systems performance in desert environments: meteorological and environmental factors
  

11:15 – 12:00 Strategies for PV production optimization in desert environments
To make solar energy a major power source, vast land areas with high solar irradiation throughout the year are crucial, and arid and semi-arid regions – especially of hot deserts-, which cover one-third of the Earth's surface (global sun belt), seems to provide the best conditions for the effective use of PV promising high energy conversion yields and playing a key role in the sustainable energy transition. However, arid regions present extreme weather and environmental conditions, including high temperatures, high UV, dust and high soiling rates, high wind, and in some cases high humidity that challenge the energy production, the long-term reliability of devices and the operation and maintenance of PV systems. These challenges also require tailored energy management processes to optimize the use of PV energy and its integration with the grid. A conservative calculation estimates that the total electricity produced in deserts by PV might produce 14 times of the world primary energy demand or in other words, only 8 % of the surface area in the desert is enough to provide global primary energy today. Different deserts in USA, Chile, India, China or MENA (Middle East and North Africa) regions presents differences and local and general solutions to optimize the production and standardized approaches need to be study. The aim of this session is to discuss current and future trends and solutions for the mitigation of these challenges with a direct impact on the optimization of the PV production. Specific topics of this session will include:

• PV productivity: best practices and models to estimate, assess and optimize PV energy generation in arid climates.
• Operation and Maintenance (O&M) challenges and cost reduction in desert climates: robotic cleaning and abrasion monitoring, autonomous and drone-based PV plant survey, early failure detection, data-driven maintenance solutions and related approaches.
• PV module reliability, soiling and temperature mitigation strategies, including innovative PV modules, components and designs for harsh environments.
• Forecasting the Energy yield of PV modules in desert environments
• Case studies of real-world field operating conditions in desert environments. Correlation between laboratory testing and field performance, energy yield and energy rating can also be discussed.
• Performance and reliability of PV inverters in desert environments. Includes advanced PV inverter functionality, voltage and frequency regulation, power quality and stability, and islanded operation.

Chairman:
Dr. Juan Lopez Garcia, QEERI, Qatar
Dr. Brahim Aissa. QEERI, Qatar

• Dr. Ben Figgis, QEERI, Qatar
  Title: Technology outlook and optimization of PV plant cleaning
  Abstract: Soiling is the largest degradation factor in PV performance in desert environments. Mechanical cleaning robots have become the primary solution, however questions remain on their impacts on PV modules and optimizing their use. Meanwhile, other technologies are in development that can aid soiling and cleaning. This presentation provides an overview of the technologies, impacts and optimization of PV cleaning for desert regions.
  
  
• Dr. Jorge Rabanal-Arabach, Universidad de Antofagasta – ATAMOSTEC, Chile
  Title: O&M challenges for PV in the Atacama Desert, Chile
  Abstract: The Atacama Desert, in northern Chile, has advantages for PV technologies which are not free of challenges to keep a low LCoE. Most dears in the LCoE are related to the costs of mounting and installation of the BoS, and to O&M of the system. These three concepts are related since having savings in the two first might negatively affects the O&M of the power plant, resulting in early failures of the PV modules, tracker system and/or power electronics. We have inspected several PV plants, observing that the main defects of discarded modules comes either from its transportation and storage during the plant commissioning, from an unsuitable design of the PV plant or because a more exhaustive maintenance is needed but was not given. For example, plastic ties that attach PV cables usually break, causing the cables to get loose and tangle around with the mounting and tracker structure. This way the tracker will pull the cable, causing damage either to the cable, to the jbox or to connections inside the box. Furthermore, due to the high UV intensity, the degradation rate of PV modules is higher than the required to achieve 25 years of warranty (0.8 %/y).
  
  
• Dr. Leonardo Micheli, Sapienza University of Rome, Italy
  Title: The impact of dust storms on the performance of PV systems
  Abstract: Dust storms are increasingly prevalent meteorological events which pose a significant challenge to PV systems. Due to the long dust transportation range, they can impact PV modules even in non-desert regions, generating non-negligible energy and economic losses. The IEA PVPS Task 13 initiative has convened global soiling experts to investigate their impact on the performance and durability of photovoltaics. This presentation presents the initial findings of this effort, combining literature evidence and expert insights, shedding light on this critical issue.
  
  
• Dr. Jim Joseph John, Dubai Electricity and Water Authority (DEWA) R&D Center, Dubai UAE
  Roadmap for improved PV module durability in desert environment based on learnings from 8 years field testing at Outdoor Field testing, MBR Solar Park UAE
  ABSTRACT: Hot desert regions of Middle east and North Africa (MENA) are becoming sites for GW-scale PV power plants with lowest solar electricity prices. To keep up with the need to have reasonable prices as well as durable and reliable PV modules, a single type of approval testing is not applicable. PV modules in the MENA region experience Hot-dry and/or Hot-humid climates. High module temperatures, low or moderate humidity, irradiance with high UV (Ultraviolet) irradiation, sandstorms, and high soiling rates with sand particles are the main challenges. In this presentation, recommendations for PV module components suitable for desert climate conditions would be made. Additionally, a proposal for hot desert test sequence will be discussed.