OHLOSS (Over the Horizon Loss)

The OHLOSS (Over the Horizon Loss) format considers the time variability of the loss due to changes in the atmospheric conditions. The combined loss is subjected to a empirical analysis using data for a specific climatic region to determine the time variability.

The median loss is first calculated by adding a correction factor to the combined loss. This accounts for differences between the long term measured and calculated values.

The median loss is then subjected to a time variability analysis for a range of time percentages. These are divided into 50% and 95% confidence factors. A 95% confidence factor means that if 100 measurements were taken over a long time period, then 95% of the measurements would be within the specified ranges.