Solar power has become a pillar of the Dutch electricity system, with 29.4 GWp installed by the end of 2025. That success undermines its own economics: because all solar parks produce in the same midday hours, they depress the price exactly when they have the most to sell. Negative-price hours on the Dutch day-ahead market reached 584 in 2025, and the solar capture factor, the ratio of the average price solar earns to the average market price, fell to 0.63–0.66. This thesis quantifies which design and operational strategies defend the lifetime profitability of a utility-scale solar park against that trend.

A 50 MWp reference plant on a 25 MW grid connection is simulated hour by hour on eleven years of measured weather and prices (2015–2025), with the SDE++ negative-price rule and full-load-hour cap inside the dispatch decision. Six scenarios add one change each to the same plant: naïve export (S0), smart curtailment (S1: no export at negative prices), a 10 MW/20 MWh battery on the firm connection (S2), the same battery trading the balancing market on a non-firm connection, curtailable by the grid operator in exchange for a lower import tariff (S3), the cap-and-floor contract for difference that replaces the SDE++ premium from 2027 (S4), and power-to-heat through an industrial heat pump (S5). The battery is priced at the end-2025 European turnkey price of €164/kWh; the higher NREL benchmark of about €395/kWh is carried as a sensitivity.

Design alone cannot repair the capture factor: at a two-to-one ratio of module to grid capacity the connection, not the array or the inverter, is the binding constraint. Smart curtailment adds €0.17–0.19M a year at no capital cost, lifts the plant's return from 6.9 % to 8.6 % on 2025 prices and is the only configuration that clears the 5 % cost of capital in all eleven market years. The battery lifts the 2025 capture factor from 0.57 to 0.93, repays its capital on day-ahead trading alone (break-even turnkey price €215–307/kWh with grid charging) and is the most valuable firm-connection configuration in both anchor years (NPV +€9.4M, IRR 9.4 % on 2025 prices); 27 of 36 battery sizes are value-positive, with a three-hour 20 MW/60 MWh optimum. The balancing market is the upside: a simple strategy without future price knowledge captures 15–40 % of its perfect-foresight pool against fee-inclusive break-evens of 18–28 %. At the higher benchmark cost no battery size repays on day-ahead trading and the case becomes a balancing decision. The non-firm connection is net-negative in every modelled case (−0.30 to −0.94 M€ a year in 2025): the discount applies only to charging while the curtailment risk falls on the exports. The cap-and-floor contract, settled against an annual reference price, cuts the year-to-year revenue standard deviation from €2.55M to €0.87M while leaving the battery's day-ahead cycling intact; a contract settled every period at a single strike would halve it. Power-to-heat is a conditional add-on carried by the heat off-taker, and a seasonal heat store cannot repay the charging capacity it requires.

On the harsher 2024 prices, and in a synthetic 2030 stress year built from the measured cannibalisation trend, the naïve plant falls below the cost of capital while the flexible configurations stay above it: flexibility becomes a condition for viability rather than an optimisation. A Dutch park should size its connection deliberately, curtail negative-price hours by default, add storage with balancing access as the upside, and treat power-to-heat as an add-on. For policy, the per-period suspension of support is incentive-compatible and belongs in the new contract, the annual reference price preserves the storage signal, and grid tariffs rather than subsidy decide the storage case at the margin.
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This thesis addresses the urgent challenge of decarbonizing large-scale industrial process heating with limited available electricity grid capacity. An integrated energy system is developed combining solar heat generation with thermal storage coupled to a high-temperature heat pump for industrial process heating up to 150 ℃ This work involves the development of individual component models capable of high temperature (100--150 ℃) operation and the integration of these components into a numerical energy system model. The model is evaluated for two industrial sectors, Food & Beverage (130 ℃) and Paper & Pulp (150 ℃), under northern and southern European climate conditions. The developed integrated model is added to the PVMD Toolbox, an advanced modeling tool developed by the Photovoltaic Materials and Devices research group at TU Delft.

Through dynamic hourly simulations over a full year, the theoretical feasibility of the integrated energy system has been demonstrated. The thermal efficiency of the solar thermal collectors averages 40% and 50% in Delft and Seville respectively. Significant reductions in peak electricity grid consumption of 70% and 100% can be achieved for northern and southern European climates respectively. Solar thermal collector count is the most important performance variable over all scenarios and seasonal heat storage is essential for peak load reductions in northern European climates. The system can be economically competitive compared to a natural gas boiler reference (80 €/MWh) in Seville, achieving a minimum LCOH of 66 €/MWh. For Delft the lowest LCOH is 119 €/MWh, not yet competitive under current gas prices but considerably less exposed to fossil fuel price volatility. ... Read more

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Co-locating photovoltaic (PV) arrays and wind turbines can improve land-use efficiency, increase utilisation of grid infrastructure, and exploit complementary renewable energy resources. However, rotating wind turbine blades and yawing nacelles cast dynamic shadows on nearby PV modules, producing transient irradiance distributions that are difficult to capture with conventional static shading models.

This thesis presents a dynamic wind turbine shading framework developed within the PVMD Toolbox. The method extends the existing sensitivity-map workflow by introducing time-varying turbine orientations and a lookup-table approach for blade rotation. To reduce computational cost, a Spherical Half-Space Test is introduced, which transforms the shading calculation from a ray–geometry intersection problem into an angular containment problem on a unit sphere. Validation against the original ray-tracing implementation showed an annual energy-yield deviation of 0.09%, while reducing total simulation runtime by approximately 59×.

The framework was applied to a 240-module PV array at the Westermeerdijk PV–wind co-location case study in the Netherlands. Dynamic turbine shading generated rapidly varying irradiance distributions, repeated bypass-diode activation, changing module and string I–V characteristics, and multi-peak P–V curves. Nevertheless, the annual array-level impact remained limited: the total dynamic shading loss was approximately 2.0%.

The results show that dynamic modelling is essential for resolving transient operating conditions and spatial loss patterns, even when annual array-level yield losses are modest. ... Read more

Agrivoltaic greenhouses combine crop production with photovoltaic electricity generation. The integration of PV modules, however, changes the amount and spatial distribution of light available to the crop canopy. Assessing this effect within a complex three dimensional crop canopy requires a modelling approach that represents both the agrivoltaic greenhouse geometry and light interception at the individual leaf level. The reviewed modelling approaches either represent an agrivoltaic greenhouse without a geometrically resolved crop canopy or include a leaf-resolved canopy but lack a PV system. To address this gap, an existing Radiance-based agrivoltaic ray tracing framework was extended with
functionality for constructing parameterised tomato plant and greenhouse geometries together with component-specific wavelength-dependent material properties. These developments were applied to reconstruct an agrivoltaic greenhouse demonstrator from the SYMBIOSYST project in Ath, Belgium, as a digital twin. Spectral ray tracing simulations over the photosynthetically active radiation range were then used to assess light absorption at leaflet, plant and canopy level.

Canopy light absorption was compared across the 0%, 33%, and 50% PV roof coverage regions of the demonstrator. Relative to the nominal 0% PV region, seasonal absorbed photosynthetically active radiation (APAR) was approximately 26% lower under 33% roof coverage and 34% lower under 50% roof coverage. Crop-row position and cross shading also influenced these differences, with neighbouring PV sections reducing seasonal APAR in the nominal 0% region by approximately 5.6%. Beyond these seasonal differences, the leaf-resolved analysis showed how light absorption varied within the canopy. The vertical APAR profiles showed that light absorption per unit leaf area increased with canopy height, with the influence of PV roof coverage becoming more pronounced towards the upper canopy. Radiation conditions also affected this distribution, with predominantly direct radiation producing stronger spatial and temporal variation in canopy APAR than predominantly diffuse radiation. Overall, the results show that canopy light absorption and distribution are shaped by the interaction between PV configuration, greenhouse geometry, radiation conditions, and canopy structure rather than by PV roof coverage alone. Although the quantitative results are specific to the SYMBIOSYST demonstrator, the extended framework can be used to construct and simulate other agrivoltaic greenhouse systems with different greenhouse geometries, PV layouts, and tomato canopy configurations. ... Read more

Hybrid Power Plants (HPPs) combining wind, solar, and storage offer a promising solution to renewable variability. This thesis presents a techno-economic analysis using DTU’s HyDesign tool to quantify how demand–generation alignment, compared to baseload operation, influences reliability and costs. On the economic side, an indicative Power Purchase Agreement (PPA) valuation framework is introduced, tailored to demand-responsive HPPs and designed to capture operational risks and uncertainties. Results show that well-aligned demand profiles achieve high reliability at lower cost, while baseload operation drives overbuilding, curtailment, and higher PPA premiums. These findings position demand-responsive HPPs as a cost-effective alternative to baseload strategies. ... Read more

This thesis details the implementation and evaluation of seven machine learning classifiers for the detection of Autism Spectrum Disorder (ASD) using resting-state functional MRI (rs-fMRI) data from the ABIDE I dataset. Two feature representations were compared: traditional Pearson correlation features and graph-based features. Logistic Regression (LR), Support Vector Machine (SVM), and Multi-Layer Perceptron (MLP) achieved the highest performance on Pearson correlation features, satisfying all predefined non-functional requirements, with average balanced accuracies up to 64.4% (SVM) and standard deviations below 2.5%. Linear Discriminant Analysis (LDA) narrowly missed the standard deviation constraint with 0.5%.
In contrast to the Pearson correlation features, graph-based features yielded consistently lower balanced accuracies, typically ranging from 54% to 59% across classifiers, underscoring their limited informativeness in the current implementation. Feature importance analysis on Pearson correlation data revealed connections between brain regions involving the inferior occipital gyrus, middle temporal pole, precuneus, and cerebellum as
consistently influential for classification. To facilitate neuroscientific exploration, an interactive tool, NASDA (Neuroimaging Autism Spectrum Disorder Analyser), was developed and demonstrated to fulfil all functional and non-functional requirements for Pearson correlation based analysis using LR as the recommended classification model.
These results highlight the dependency of classifiers performance on the quality of input features and contribute to ongoing efforts to localise robust neurological biomarkers for ASD. ... Read more

With the enormous rise in installed photovoltaic (PV) modules over the past decade, it is to be expected that soon, a massive increase in decommissioned PV modules will arise. Current PV modules are difficult and energy-intensive to recycle, leading to some of the most valuable materials going to waste. To prevent this, new PV module structures have been proposed, with the most promising structure containing a layer of air between the module’s front glass and the solar cell. Due to this replacement of the ethylene vinyl acetate (EVA) layer, the air-filled modules are easier to disassemble and recycle. However, it lowers the module efficiency due to a mismatch in the refractive index of the front glass and air. To overcome the refractive index mismatch of air-filled modules, this study evaluates the performance and degradation behaviour of self-manufactured, liquid-filled PV modules, which are subjected to humidity freeze accelerated ageing and their results are compared to air-filled and EVA-laminated mod-
ules. To achieve this, suitable liquids are selected. Subsequently, several one-cell mini-modules are hand-manufactured, which are filled with air, the selected liquids, and laminated with EVA. The results are obtained by subjecting the modules to 30 cycles of humidity freeze testing and by measuring their electrical characteristics under standard testing conditions. Initial performance measurements show that all four tested liquids, including water (3.7%), polydimethylsiloxane (PDMS) (6.2%), mono propylene glycol (MPG) (5.1%), and glycerol (5.1%), offer substantial efficiency improvements over air-filled modules, with PDMS even slightly outperforming EVA (5.5%). A major point of failure is the PIB edge seal, especially at the liquid injection points, indicating a need for improved manufacturing techniques. The module failures also allowed for disassembly trials, which show that liquid-filled modules can be completely disassembled with ease, allowing for full material recovery. This highlights the reusability potential of liquid-filled designs due to the absence of more permanent encapsulant layers like EVA. The humidity freeze accelerated ageing, subjects the modules to extremely low and high temperatures of -40 °C and 85 °C, whilst also subjecting them to 85% relative humidity. Intermediate visual and electroluminescence inspections revealed mechanical failure in air-filled modules due to edge seal flattening and cell breakage. Whilst after the full 30 humidity freeze cycles the relative degradation in module efficiency in both PDMS and glycerol encapsulated modules (both 5.2%) are comparable to that of an air-filled module (5.5%) but worse than that of EVA (3.9%), whilst the module encapsulated with MPG shows the lowest degradation (2.8%). These results highlight the potential of MPG as a stable encapsulant and underscore the importance of redesigning the liquid injection method for reliability of the polyisobutene edge seal


The humidity freeze accelerated ageing subjects the modules to extremely low and high temperatures of -40 °C and 85 °C, whilst also subjecting them to 85% relative humidity. Intermediate visual and electroluminescence inspections revealed mechanical failure in air-filled modules due to edge seal flattening and cell breakage. Whilst the full 30 humidity freeze cycles show that relative degradation in module efficiency in PDMS and glycerol encapsulated modules (both 5.2%) are comparable to those of an air-filled module (5.5%) but worse than that of EVA (3.9%), whilst the module encapsulated with MPG shows the lowest degradation (2.8%). These results highlight the potential of MPG as a stable encapsulant and underscore the importance of redesigning the liquid injection method for reliability of the polyisobutene edge seal. ... Read more

Hybrid PV-wind systems improve land use efficiency but introduce shading interactions, with wind turbines potentially reducing PV output. The PVMD Toolbox is an energy yield simulation tool that accounts for a PV module’s position, mounting, and surroundings, enabling detailed shading analysis. However, high accuracy in modeling how the module perceives its environment comes at significant computational cost. A selective skydome refinement method was developed and implemented in the PVMD Toolbox to perform accurate and efficient shading analysis for PV modules in complex environments. The method begins with a coarse-resolution skydome simulation to identify shaded regions, which are then selectively refined, along with a surrounding buffer. Sensitivity values are recalculated only for the refined areas using targeted ray tracing, while the rest retain values from the initial simulation. This approach reduces ray tracing operations by over 70% and total simulation time by approximately 90%, with a relative DC energy yield error of less than 1%. The method was validated across different initial resolutions, demonstrating a consistent trade-off between computational efficiency and accuracy. In large-scale PV-wind layouts, it captured spatial shading effects reliably and highlighted the importance of fine-resolution input data. ... Read more

In the Netherlands, 3% of people above 4 years old are diagnosed with autism. Diagnosing is currently done with a psychological assessment, but classifying people with autism using resting state functional magnetic imaging, or rs-fMRI, has become promising. The goal of this project was to see if new features could be found, based on the graph of rs-fMRI data stored in the Autism Brain Imaging Data Exchange (ABIDE) dataset, that had a significant positive influence on the accuracy of a predictive model. To do this, several feature selection modules were researched and coded in Python. Subsequently, these were tested with the features and classification methods created by our partner subgroups. The best performing model, using all data, had an accuracy of 74.26% and a sensitivity of 65.35%. The best performing model using graph features, on all data, had an accuracy of 60.4% and a sensitivity of 46.6%. This indicates that there were no graph features developed that had a significant positive influence on classifying whether someone has autism. ... Read more

As global temperatures rise and energy demands increase, the need for clean, renewable
energy sources is more critical than ever. Solar energy is one of the key solutions, with the
majority of solar panels currently on the market being made from crystalline silicon. However, emerging photovoltaic (PV) technologies such as perovskite solar cells have already demonstrated efficiencies comparable to those of silicon solar cells, making them a promising contender to achieve even higher efficiencies.

Most of the layers in perovskite solar cells are deposited via spincoating, which is a fast and easy process but can only be done on laboratory-scale. However, deposition through thermal evaporation offers significant advantages, enabling fabrication of nanometer-thin films and facilitating large-scale fabrication needed for future industrialization of perovskite solar cell. Therefore, this research aims to develop perovskite solar cells entirely through thermal evaporation.

The reported number of hole transport materials deposited through thermal evaporation is limited. Recently, fully thermally evaporated perovskite solar cells have been created using the hole transport materials MoOx and TaTm, and these hole transport materials will be studies in this thesis.

The MoOx and TaTm were used as single and double hole transport layer to replace the
reference layer of spincoated PTAA. It was found that the MoOx in direct contact with the pervovskite resulted in a chemical reaction, which negatively affected the energy alignment. The MoOx also showed poor charge carrier selectivity, resulting in high interfacial recombination. Great hole extraction from the perovskite was observed for TaTm, however, a misalignment of the band energy with the electrode hindered the hole collection. Improved hole transfer was found with MoOx and TaTm being used a double hole transport layer. Here, the TaTm functions as a passivation layer between the MoOx and perovskite, while effectively blocking the electrons. In turn, the MoOx improved the energy alignment from the TaTm to the electrode to improve the hole collection.

A thickness optimization of the hole transport layers was also performed. For MoOx as
single hole transport layer, it was found that number of oxygen vacancies decreased with
thickness, leading to less recombination. No change was observed for TaTm as single hole
transport layer when varying the thickness. However, as a double hole transport layer with MoOx, increasing the thickness of TaTm led to an increase in Voc . Ultimately, a thin layer of 2 nm MoOx with a 5-nm thick TaTm showed the most promising results, demonstrating a final efficiency of 4.73%.
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As the energy demand keeps rising and the need for clean, affordable energy increases, the switch to completely sustainable energy production comes closer and closer. Solar cells are expected to play a big role in this energy transition. However, the technology of the most used type of solar cell, crystalline silicon, is nearing its limit. This calls for other novel technologies that could surpass it. One of these promising technologies is the perovskite / c-Si tandem cell. This type of cell has shown promising results in recent years, but for it to be commercialized and challenge the current technologies that dominate the market, some steps need to be taken. This thesis focuses on hysteresis, a behaviour commonly shown in perovskite cells, resulting in an uncertainty when measuring the characteristics of these cells. The most common explanation for this behaviour has been due to ion migration under certain conditions. This report, however, looks at hysteresis from a different perspective. It investigates the effect of defects on the hysteresis behaviour, continuing on previous research on this mechanism. It is argued that the defects trap charge near the interfaces, affecting the charge extraction and with that the amount of recombination in the cell. This hypothesis is researched by modelling a state-of-the-art perovskite / c-Si tandem cell in TCAD Sentaurus. This research investigates multiple important parameters to these defects, such as defect density, distribution, energy level, and capture cross-section. With these variables, the hysteresis behaviour as a result of the defects is explored. These results are then used to compare the hysteresis behaviour of the tandem cell with a similar single-junction cell, after which the difference between the two is analysed. It is found the two types of cells have similar hysteresis behaviours, but not equal. With the main deviation finding its origin in the current-limiting that can be displayed by tandem cells. ... Read more

As policies and technological advancements accelerate the energy transition, more resources are required to develop sustainable pathways for end-of-life solar modules. Chemical delamination is an attractive option for solar recycling as it has the potential to separate the layers of a module and recover the cell intact. In this work, four primary testing factors were considered to optimize the process: solvent, temperature and residence time with the goal to reduce the reliance on fossil fuel based solvents, improve the reliability of cell material recovery and to attempt to recover cell materials intact. A preliminary solvent screening found three sustainable solvents that could replace current fossil fuel based recommendations. A subsequent optimization under atmospheric conditions found that 60% of the encapsulating EVA could be removed in 3 hours at 160°C. Additionally, this process was observed to be scalable. This research offers a baseline result for chemical delamination that can be built upon to advance the technical and economic viability of this solar recycling method. ... Read more

The main goal of this project is to utilize a commercially available OpenBCI Ultracortex IV for the measurement of Electroencephalogram(EEG) signals. A pipeline consisting of preprocessing, classification and extraction is employed to transform the motor execution EEG signal into a singular Left or Right output. This output is then further displayed on an Interface that offers the option to either calibrate or play a simple game.

The Ultracortex and relevant software were used to determine the sensor layout, with the placement of the sensors focused on areas which exhibited high cortical activity during motor execution. Experiments were strategically designed to optimize our chance of successful readings and OpenVIBE was used in conjecture with preprocessing filters to save the raw and filtered data which was further sent to the Machine Learning group.

The collected data was analyzed through Spectrograms, Power Spectral Density(PSD) and Event-Related Desynchronization/Synchronization(ERDS) plots. The analysis aimed to confirm whether the desired activity occurred and whether the observed patterns resemble those documented in other research papers.

The data from the headset is live-streamed to the interface via Lab Streaming Layer(LSL) where it undergoes further filtering before being sent to the Machine learning group. This process was done through python libraries which then allowed for efficient and effective communication between the other groups. ... Read more

This thesis addresses a critical challenge in the field of renewable energy, focusing on the efficient utilization of Photovoltaic-thermal (PVT) systems. Much research has already been done on PVT and there exist many thermal simulation models. However, many of the researches done and existing thermal models are restricted to a specific collector archetype which gives less flexibility in experimentation between multiple archetypes. In addition, many experimental researches require a physical setup for measurements and thermal simulation models would need to be altered for different research approaches and collector archetypes. The primary objective of this thesis project is therefore to create a performance simulation framework model that is suitable for the calculation of the thermal and electrical performance for any PVT archetype. It aims to develop and implement a toolbox application encompassing heat transfer models that can establish a foundation for future research on PVT collector optimization, PVT system integration and PVT performance analysis. This toolbox application will be implemented into the PVMD Toolbox Vogt et al. (2022), housed within the Photovoltaic Materials and Devices research group at TU Delft.

Selected PVT collector: This research has visualized that there is a wide variety of PVT archetypes that can be used for current and future generations of PVT collectors. PVT collectors can be combined with heat pumps, refrigeration pumps, phase change materials and multiple forms of heat collection via fluids or air. These combinations can all contribute to high electrical and thermal efficiencies

Numerical heat transfer model and assumptions: It is possible to calculate heat transfer rates of complex designs when using a Finite Element Method (FEM) approach to calculate the heat transfer within the collector. With the proper convective and radiative equations to the environment, the heat transfer inside the collector and to the environment could be calculated without needing an experimental setup.

Performance calculations: The performance calculations gave insight into the simulated behavior of the PVT collector when operating in real-world conditions. Ranging the inclination angle from 0 to 60 degrees showed that the thermal efficiency became around 55% at an irradiance of 800 W/m2 at 45 degrees. It also showed that differences in dimensions like pipe thicknesses and number of pipes did not affect the thermal performance that much. The daily performance calculations illustrated that the thermal energy lost to the environment can be three times as high as the incoming solar energy due to the low ambient temperatures compared to the inflow temperature. In the summer, PVT can achieve high total efficiencies of around 75% making PVT suitable during those times. The economic analysis showed that a PVT collector can have an LCOE of $0.08/kWh which is lower than the $0.13/kWh of conventional PV. ... Read more

With the rapid increase in renewable energy demand, various kinds of renewable technologies have been realized. Of particular interest is that they require a certain amount of space, and they may conflict with other land utilization purposes such as food production, protected nature areas, and life-sustaining services, thus the land use pressure is multiplying. For this reason, spatial management is required to analyze the optimal locations for such implementation.

A site suitability analysis is one of the applications that could be used to address this issue. Typically, it was done by mainly examining two constraints: technical and economical criteria, and excluding natural locations from the analysis. The challenge is that without the consideration of an environmental aspect, rich nature areas that are not included in the protection zones, cannot be identified. Therefore, this research aims to conduct the site suitability analysis for ground-based solar energy technology in the Netherlands and advance a suitability model by incorporating the environmental criterion in the assessment.

The study was designed into four phases. Beginning with Phase 1, a compatibility index was developed based on the concept of area degradation. This technique evaluates the compatibility level of an area in terms of an environmental constraint by quantifying the existing land degradation. Subsequently, it was combined with other factors from technical and economical criteria, constructing the suitability index in Phase 2. The Analytic Hierarchy Process (AHP) is a method that was adopted in this combination process. At the end of this phase, five suitability maps were generated from the shift in focus among technical, economical, and environmental criteria. Later in Phase 3, an additional suitability map was developed by analyzing the locations of existing solar projects in the Netherlands. Finally, an example of applying the suitability results was demonstrated in Phase 4 through a case study that set an energy target of 35 TWh as a minimum requirement for solar energy development.

As a result, the preferable locations were specified by the suitability model for this energy realization. They are mostly distributed in the western part of the country (Zeeland, Zuid-Holland, and Noord-Holland provinces) around the major urban and industrial sectors. The proportion of land features in these areas is comprised of 0.4% for border of infrastructure, 17.9% for natural areas, 19.3% for urban areas, and 62.4% for agricultural areas. ... Read more

Indonesia has recently made a target to shift to more sustainable and renewable energy sources through its energy transition commitment to achieve net zero emissions by 2060. It is widely reported in various literature that the country has significant solar energy potential. At the moment of writing, the current solar PV in construction, potentially the largest in Indonesia, is the Cirata floating solar PV project with an installed capacity of 145 MWp. This study shows that the technical potential of floating solar PV in Indonesia is 33 GWp at 5% water occupancy. Meanwhile, this study finds that the economic potential of floating solar is significantly lower than its technical potential, with only 6.4 GWp at 5% water occupancy. There are various support schemes to increase the economic potential of floating solar in Indonesia. The FSPV can become an alternative solution to renewable energy sources for Indonesia’s energy transition plan. In addition, a potential scenario is provided in this study to achieve the energy transition in Indonesia. ... Read more

Grid congestion, which results from a larger demand for electricity transport than the available transport capacity, is a challenge in the Dutch energy transition. The growing pace of decentralized renewable energy development in less densely populated areas and the electrification of demand leads to congestion, which potentially hinders the connection of new renewable projects to the grid and slows down the energy transition.

Due to the intermittent behaviour of renewable resources, the grid connection capacity is not used to its full capacity at all times. Cable pooling is introduced as a possible solution to congestion, allowing an existing and a new renewable resource to share a grid connection and improving the utlilisation of the current grid infrastructure.

This thesis’ main objective is to develop a calculation framework to assist developers to evaluate the economic potential of a cable pooling location by optimizing the Net Present Value (”NPV”) of a shared grid connection, considering technical, regulatory, legal, and financial aspects. It aims to provide developers with a tool for making a preliminary decision on whether to continue development for a potential cable pooling location.

The Dutch context is used to identify different grid connecting possibilities, different combinations of wind and solar to form a hybrid farm and different revenue streams. These are used in a methodology to find the optimal installed capacity of the added resource and the impact of on-site storage to one of the hybrid farms. The approach considers the influence of market prices on the technology specific cable pooling business case at an hourly level and accounts for long-term market developments. Other factors accounted for in the tool are the hourly export capacity, defined as the residual space after the export of the existing farm, land size and costs of installation.

A case study of a solar farm oriented to the east-west is used to test the tool and draw conclusions on the potential of cable pooling for this case study. The additions of a wind and solar resource with either south or east-west generation all yield positive NPV values with the highest values seen for the wind addition.

Sensitivity tests for technical and economic inputs show that the results are sensitive to weather data and various economic inputs, but the results of this case study are robust. The case study however considers a relatively large grid connection. Generalizing the results by considering a smaller grid connection shows the value of complementary production patterns.

The impact on the cost-benefit framework by adding a battery is considered. The addition of a battery adds value by peak-shifting the produced energy, but not enough to cover the costs of the battery without any subsidy or alternative revenue streams.

In conclusion, cable pooling shows potential for this case study, for different revenue streams and additions. The tool used to obtain the results can be tailored to different case studies and input scenarios and shows the economical attractiveness of a cable pooling location, based on the Dutch context. The Dutch context shows a promising potential for cable pooling as a method to deal with congestion, but not many projects are present yet. Considering different parties sharing one grid connection, coming to an agreement on the terms can form a hurdle. Therefore, the introduction of more transparent cable capacity calculations by DSOs and a separate subsidy for cable pooling projects could help incentivize the development of more cable pooling projects. The impact of developments such as the ”Use-itor-lose-it” on the cable pooling potential should be monitored closely. Other solutions to dealing with congestion, such as using the fault reserves, should not be disregarded. ... Read more

Increasing the energy yield per unit area of Photovoltaic (PV) modules is one of the main challenges the PV technology is currently facing. In search of ways to address this issue, solar tracking systems are a favorable solution, which according to literature can enhance the energy yield by up to 45%. Another way is to opt for high-efficiency solar cells. Tandem cells have emerged as a promising technology, achieving efficiencies of over 30%. The integration of these tandem cells with sun-tracking techniques suggests high-performing solar modules. The present work develops a solar tracking model to simulate the performance of tracking PV systems equipped with tandem modules. The model will be incorporated into the PVMD toolbox, a PV modeling software developed within the PVMD group. This software can predict the energy yield of PV systems using self-consistent models for each aspect of the energy conversion.

The current version of the toolbox makes it impractical to include solar tracking due to the time-consuming nature of ray tracing used to compute the irradiance. Ray tracing generates sensitivity values that illustrate how sensitive is the module to incoming irradiance from any direction in the skydome. Initially, this work focuses on substituting ray tracing with an alternative faster approach to express sensitivity based on view factors. The view factor and ray tracing method are compared with respect to computational time and extent of agreement. It was found that the view factor can significantly reduce the computational time from over 12 minutes, as required in ray tracing, to a few milliseconds for a single module orientation. Additionally, the view factor method generates sensitivity values closely matching those from ray tracing. For instance, a mean RMSE of 1.2% between the two methods is achieved, for an albedo of 0.2 and module tilt of 30 degrees. Sun tracking aims to locate the module orientation that maximizes the in-plane irradiance. Directly calculating the irradiance for every orientation to identify the optimal, is not a viable option, as it requires substantial
time. Thus, sun tracking was expressed as an optimization problem and algorithms were employed to address it. Based on the prevailing sky conditions three optimization case studies were defined on an hourly basis: sunny, cloudy, and intermediate hours. Multiple algorithms were compared across the three cases with selected criteria the convergence to the optimum and runtime. Matlab’s surrogate solver and an author-developed algorithm were selected, as a satisfying solution, compromising those two criteria.

Finally, energy yield simulations were performed on perovskite-silicon tandem modules mounted on a dual-axis tracking system. Four locations were selected, representing different real-world conditions: Stockholm, Athens, Bombay and Bogota. Results show the module’s tilt dynamic adaptability to sky conditions: increas- ing nearly to the sun’s zenith when direct light dominates, and lowering when diffuse light is prevalent. Furthermore, the seasonal fluctuations of the energy gain of tracking systems are explored, with locations further from the equator such as Stockholm exhibiting the highest variability of 19% in winter to 36.9% in summer. In addition, the annual energy gained among the locations was found to span between 24.8% (Bogota) and 34.1% (Bombay). An important finding is the direct proportionality in gains from absorbed irradiance to DC and AC yields, illustrating a 1:1:1 ratio. Then, the effect of tracking technology on mismatch losses of tandem modules was examined. Results indicated that tracking has little impact on both the current and power mismatch. For example, the power mismatch losses slightly increased from 1.10-1.46% in static PV systems to 1.29-1.77% for tracking topologies in the locations examined. Moreover, the tandem’s annual energy gain is compared to silicon heterojunction modules. The analysis showed similar gains across locations for both cell technologies. ... Read more

The Indonesian aims to greatly increase the share of renewable energy sources in the electricity generation mix. Rooftop solar photovoltaics (RTSPV) are a potential generation method that can be used in support of this, with Bali chosen as a case study. No estimates of the total technical and economic potential of RTSPV on Bali exist in academic literature. Low spatial resolution statistical methodologies exist to estimate the technical potential of RTSPV, but these are not accurate on the sub-national scale of Bali. Methodologies with a medium spatial resolution are most suitable for an area of the scale of Bali, however existing methodologies cannot be used due to incomplete cadastral data. In this thesis a novel methodology is introduced that allows the use of incomplete cadastral data, in combination with land use data, to estimate the total rooftop area in a region at a medium spatial resolution. The total rooftop area is then used to estimate the total technical potential and the total economic potential. Using this method, the rooftop area of Bali is estimated to be 130 km2, and the technical potential 22.9 TWh/year. The economic potential for RTSPV is estimated to be zero, as RTSPV cannot compete with conventional generation methods at current capital costs (CAPEX) of RTSPV components of 1200 USD/kWp. It is estimated that at a CAPEX of less than 870 USD/kWp sufficient electricity can be generated annually to fulfill the estimated annual demand of Bali of 5.7 TWh. 96% of the entire technical potential can be achieved at or below the cost per kWh of conventional generation methods if the price of RTSPV installations decreases to below 650 USD/kWp. If the compensation paid by the Indonesian state electricity company PLN for RTSPV electricity that is supplied
to the grid is increased from 65% to 100% of the consumer electricity price, residential RTSPV installations can become economically viable at the current CAPEX of 1200 USD/kWp. This thesis will enrich existing literature on RTSPV potentials by introducing a novel methodology that can be applied in other regions with incomplete cadastral data. In addition, it provides a blueprint to estimate RTSPV potentials for other parts of Indonesia, and it supports policy makers by giving insight in factors that influence the economic potential of RTSPV on Bali and in Indonesia as a whole.
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