Why is 1-min data essential for solar project financiers?

Solar project financing is a complex and risky process that relies on accurate and reliable data on resource and variability.

One of the key challenges for solar project financiers is to assess the expected energy production and revenue of a project over its lifetime, considering the uncertainties and fluctuations of the solar resource.

Common metrics used to overcome financial uncertainty

Project financiers typically quantify the uncertainty of solar resource by using probabilistic metrics, such as P50, P70 and P90. These represent the probability of exceeding – or falling short of - a certain level of energy production in a given period.

For reference, P50 denotes a 50% chance that actual energy production will be higher than the P50 value, and a 50% chance it will be lower. Similarly, P70 describes a 70% chance energy production will be higher than the P70 value, and a 30% chance it will be lower.

Figure 1: P50, P75, P90 and P99 value represented in a normal distribution

But … probabilistic metrics have blind spots

Critically, these widely used metrics are highly dependent on the quality and resolution of the solar resource data used to calculate them.

Low-quality or low-resolution data can lead to inaccurate or unrealistic estimates of the energy production and revenue of a solar project, which can have serious consequences for the project's financial viability and its attractiveness for investors.

One of the most important aspects of solar resource data quality is the temporal resolution.

Why?

If the temporal resolution of solar resource data is too coarse (e.g., hourly or daily), it will miss several short-term fluctuations or peaks of the solar irradiance that can have a significant impact on a project’s energy production and revenue.

That’s why the industry needs to move towards collecting weather and solar irradiance data at shorter intervals. By accurately capturing the solar irradiance variability, weather and PV power potential of a chosen solar plant site, 1-min data helps bring financial certainty to a project.

Four reasons why project financiers need 1-min data

Through extensive research and studies, Solargis has found that one of the best temporal resolutions for solar project financing is 1-minute solar data. This is because solar project financiers can use 1-min solar data to help them:

1. Capture most of the relevant variability and frequency distribution of the solar irradiance, which affects the revenue of a solar project and energy production, such as clipped energy by inverters.
2. Model and simulate different types of solar technologies and systems more accurately, such as PV modules, inverters, trackers, and batteries.
3. Analyze and optimize different aspects of a solar project in more detail, such as string and battery sizing, design, layout, orientation, shading, losses, and performance ratio
4. Assess and mitigate the risks of a solar project more robustly and transparently, such as hedging, insurance, and guarantees

1-minute solar resource data is essential for solar project financiers to obtain realistic and reliable estimates of the energy production and revenue of a solar project.

To read our 1-min data blog series, please click on one of the links below.

• Solargis’ approach to 1-minute data
• 4 reasons why PV project designers need 1-minute data

To find out more about how we can support you with your solar data needs, please get in touch here.