Passive solar design relies on the sun's change in degrees over a year. In the winter months, the sun will be lower down while in the summer it will be more directly in the sky. This will be exaggerated on the polls and negligible on the equator.

How it works

Heating

The idea is that you can control how much sunlight gets into your house over the year with architecture. Letting more light in the winter months and less during the summer.

Cooling

Cooling relies on the earths temperature 8 feet down. It is normally around 55 degrees. This combine with a thermal mass that is 8 feet deep can help keep a static baseline temperature.

Thermal Mass

This falls apart when the sun goes down. So to keep the temperature you can use something that will keep or hold the temperature. Most people use stones.

Distribution

Once solar heat is transferred into the building through windows and absorbed into the thermal mass it will be transferred by convection, conduction, and radiation.

Sources

https://www.firstinarchitecture.co.uk/architecture-design-basics-passive-solar-design/