Week 1 - Refining my Framework and Defining Experimental Ranges

Welcome back to my senior project blog! This week, I focused on strengthening the scientific foundation behind my project and finalizing specific environmental ranges that will be used in my experimental testing. Since my project investigates the effects of ambient temperature on photovoltaic (PV) performance when irradiance is held constant, along with the effects of humidity and thermal stress, it was important to make sure my research was grounded and accurate in regards to existing literature.

I began by revising prior studies on PV temperature coefficients and semiconductor behavior. Classic analyses revealed that open-circuit voltage and efficiency decrease as temperature increases due to increased carrier recombination. Review studies reported that PB modules typically lose around 0,4-0.5% efficiency per increase of 1 °C in operating temperature. However, most of these studies were conducted under sunlight or solar simulator conditions, thus inherently coupling irradiance and temperature. This makes it difficult to isolate the effect of ambient temperature alone, which is the main gap I am addressing.

I also reviewed literature on humidity and degradation mechanisms. Studies emphasize how long-term humidity exposure contributes to corrosion and module degradation, but short-term effects under controlled chamber testing remain less explored. Additionally, IR thermography research demonstrates how IR imaging can detect hotspots and non-uniform heating. However, this is rarely coupled with independently controlled ambient temperature and humidity. Approaching this gap, adds layers of nuance and novelty to my controlled chamber work.

After strengthening my literature base, I finalized the environmental ranges for testing. Ambient temperature will be varied from approximately -20 °C to 60 °C, capturing both extreme cold and high operating temperatures observed in real-world systems. Relative humidity will range from 5% to 50% RH during initial trials, with controlled expansion as needed. Irradiance will be independently adjusted between 400 W/m² and 1000 W/m² using externally positioned high-intensity LEDs to prevent direct radiative heating of the panel. This configuration allows accurate separation of ambient temperature effects from irradiance-induced heating, as shown in my proposal.

By the end of the week, I organized my research into structured layers. These include temperature-voltage relationships, humidity interactions, thermal stress behavior, and infrared gradient mapping using MATLAB. I also refined my stabilization procedures, measurement timing, and calibration strategy to ensure consistency once my actual experimentation process begins.

Overall, I spent my first week building precision for my research plan. I strengthened my theoretical foundations, defined experimental temperature ranges, and aligned my methodology with documented gaps in prior PV testing. Next week, I will move into deeper planning and begin calibration and validation to prepare for my trials.