Clir’s detectors: Understanding the impact of temperature on PV farms

Depending on the environment and the design specification, temperature losses can have a huge impact on the production and risks of a solar PV farm.

Clir’s dataset identified that hot and wet conditions can lead to high rates of inverter failures, causing overheating, moisture ingress and condensation, and leading to electrical failures. Clir’s platform helps owners identify how temperature losses are impacting their farms and how this impacts budget deviation.

Solar panel overheating risks

Solar modules are typically rated for standard conditions, which are 1000 W/m2 and 25 ºC. During operation, there can be an increase in PV panel temperatures due to higher ambient temperatures, higher solar irradiance on the modules or a lack of wind to cool down the modules.

These temperature increases are detrimental for two main reasons:

1. When a PV module cannot cool, voltage is reduced which lowers power output.
2. Temperature increases exacerbate the possibility of degradation and failures, as elevated temperatures increase stresses associated with thermal expansion.

Clir's temperature detector

Clir's temperature loss detector will identify when there is a high cell temperature and quantify the loss. When solar modules are in operating conditions, there can be an increase in module temperature. When the PV module cannot cool to its standard operating condition, higher temperatures affect the operation by reducing its voltage, thereby lowering the output power. Underperformance due to temperature losses can be a large source of lost energy and is critical to understanding why a farm may have performed above or below budget.

Temperature detector uses

Temperature corrected performance ratio

Temperature corrected performance ratio an industry standard measurement for understanding the power output at a solar PV farm. It is a measure of actual power delivered versus expected power delivered. Clir has built out a KPI that leverages the temperature detectors to understand how temperature is impacting PV farm performance and use the corrected performance ratio to benchmark against peers.

By adding the temperature back to the production, it removes the effects of uncontrollable temperature loss on the performance ratio. The performance ratio is a metric focused on losses due to controllable causes. Temperature corrected performance ratio is seen as a more insightful metric as it provides a clear view of controllable losses on the performance ratio.

Budget performance

Underperformance due to temperature losses are uncontrollable but a potentially large source of lost energy. Understanding temperature loss is critical to understanding why a solar farm may have performed above or below budget. By examining uncontrollable losses due to temperature, owners can explain budget deviations.

Understanding temperature losses