Improve solar resource estimates with a bias-corrected dataset
Accurate solar resource data is critical when assessing sites for development. Satellite data bias correction, also known as ground tuning or site adaptation analysis, uses short-term measurements from the site to improve the accuracy of long-term satellite-derived solar radiation data for the location.
Xweather uses advanced statistical techniques to detect and correct systematic differences (biases) between the satellite data and ground measurements. This process reduces the uncertainty in the long-term resource data, allowing you to predict a project's feasibility and energy yield with more confidence.
Satellite data
Satellite data provides a readily available historical archive of solar resource data for most locations. Single-source satellite data is consistent and reliable, but it comes with ±5% uncertainty on average.
On-site observations
On-site observations from high-quality pyranometers reveal the ground-truth conditions. However, a limited sample of short-term observations might not reflect typical long-term conditions.
MOS-corrected dataset
Xweather combines on-site observations, long-term satellite data, and NWP weather data in a multi-linear statistical correction called Model Output Statistics (MOS) to produce a site-specific, bias-corrected dataset.
Cut uncertainty in half
With just 3 months of on-site observation data, we can reduce the uncertainty in the historical satellite data by 25%. With 4 months of data, we reduce the uncertainty by 42%. Accuracy improves with more data, but we find the best return on investment comes from 12 months of observations, which will reduce your uncertainty by 57%.
| On-site observation data | Satellite GHI uncertainty (%) | Xweather improvement |
|---|---|---|
| 0 months | 5.00 | - |
| 4 months | 2.88 | 42% |
| 8 months | 2.41 | 52% |
| 12 months | 2.17 | 57% |
| 18 months | 1.95 | 61% |
| 24 months | 1.81 | 64% |
Put our expertise to work
Our MOS approach is driven by a dedicated team of industry experts, forecast analysts, statisticians, and data specialists with over 20 years of experience and knowledge.
When you need more certainty for solar assessment studies, let us do the hard work of correcting the bias in your data. We're here to help!