Solar Time Calculator app for iPhone and iPad

The Solar Time Calculator can easily convert clock time (standard or daylight saving time) to solar time and solar time to clock time.

Solar time is based on the position of the sun relative to a local position (longitude). Solar time usually differs from clock time, though the magnitude of the difference varies. Thus, solar noon (when the sun is directly overhead) generally occurs at a time other than exactly 12:00 PM clock time. This difference is up to about +/– 45 min for most locations and is caused by the two factors: date and location. The Solar Time Calculator uses these factors to calculate the actual solar time relative to the position of the sun.

Solar time is useful when conducting shading analyses, optimizing photovoltaic array orientation, and performing other calculations in the field of solar energy systems.