Pysolar is a collection of Python libraries for simulating the irradiation of any point on earth by the sun. It includes code for extremely precise ephemeris calculations, and more.

• The latest release, 0.6, is still good: https://github.com/pingswept/pysolar/releases/tag/0.6 but HEAD has just had bunch of changes. They have been validated for Python 3.4, but not the 2.x series. *

Also, the API has changed slightly:

• Pysolar now expects you to supply a timezone-aware datetime, rather than a naive datetime in UTC. If your results seem crazy, this is probably why.
• Function names are now lowercase_separated_by_underscores, in compliance with PEP8.

Assuming you have Python 3.4 or higher installed, you can install Pysolar with pip:

sudo pip install pysolar

Documentation now appears at docs.pysolar.org.

All contributions go through pull requests on Github.

Editing the documentation is particularly easy-- just click the "Edit on Github" link at the top of any page.

Code contributions are welcome under the terms of the GPLv3 license. If you're unfamiliar with Github, you could start with this guide to working on open source projects.

You can email the original author Brandon Stafford at brandon at pingswept org. Please understand that I wrote (most of) Pysolar around a decade ago when I worked in the solar industry. Now, I'm an electrical engineer who just maintains Pysolar as a fun hobby.

Please report bugs to the issue tracker on Github; I am automatically notified when a new issue is opened.

Pysolar is licensed under the GPLv3.