# Passive solar and natural cooling

Buildings designed to gather or shed heat and light without machines.

Source page: https://www.materialinsights.org/energy/e_passive/

Capture · Solar · No. 24

- Capture
- Output: Heat, cooling, light
 Capture · Solar · Foundation · Energy

A dark wall behind glass can soak up the day's sun and release it indoors 8-10 hours later, with no machines.

Chart: Illustration: Passive solar and natural cooling

##### Where it comes from

Chart: Map of where it comes from

Buildings gather or shed heat and light through their shape and materials; a Trombe wall at Zion supplied a fifth of its building's heating.

##### Three things to know

1. Evaporative coolers can chill passing air by about 8-22 C at under half the cost of air conditioning.
2. Seawater cooling draws water from about 900 m deep and can use 83-94.5% less electricity.
3. Radiative cooling surfaces have stayed 4.9 C below air temperature in full sun in laboratory tests.

##### The journey

1. 1 **Sun and sky**Free heat, light and night-time cooling
2. 2 **Design**Orientation, windows, overhangs and shading
3. 3 **Thermal mass**Thick walls store heat for hours
4. 4 **Air movement**Ventilation, windcatchers and earth tubes
5. 5 **Comfort**Warm winters, cool summers, daylight indoors

##### Go deeper pick a tab to open it in full

## Other sections

- [Overview](https://www.materialinsights.org/energy/e_passive/overview/index.md)
- [Correlation](https://www.materialinsights.org/energy/e_passive/correlation/index.md)
- [Efficiency](https://www.materialinsights.org/energy/e_passive/efficiency/index.md)
- [Techniques](https://www.materialinsights.org/energy/e_passive/techniques/index.md)
- [Resources and labour](https://www.materialinsights.org/energy/e_passive/resources/index.md)
- [Impact on the biosphere](https://www.materialinsights.org/energy/e_passive/biosphere/index.md)
- [Relationships](https://www.materialinsights.org/energy/e_passive/links/index.md)