"Solar Panels That Work Even in the Dark of Night"

"Unlock the Night: Solar Panels That Work 24/7 with Radiative Cooling"

Mostly, the biggest problem with solar power is that the sun doesn’t always shine. If solar panels can’t produce power at night or when it’s cloudy, how can we depend on them as a round-the-clock source of electricity?

Basically, conventional solar panels only work in daylight, so you need expensive battery storage to enable solar-produced power to be used at night. Now a team at Stanford University in the US has tested solar panels that keep generating electricity around the clock.

So once we look at the working principle of a radiative cooling solar system, it combines solar energy collected during the day with radiative cooling at night to generate power continuously.

Here's how it works:

1. **Solar Energy Harvesting (Daytime):**

   - During daylight hours, traditional solar panels absorb sunlight and convert it into electricity through the photovoltaic effect.

   - These solar panels also absorb heat from sunlight, causing them to become warmer than the surrounding environment.

2. **Energy Conversion and Storage (Daytime):**

  - Solar panels produce direct current(DC); the sun shining on the panels stimulates the flow of electrons, creating current. Because these electrons flow in the same direction, the current is direct. An inverter can convert DC to AC.

   - The electricity generated by the solar panels can be used to power devices or stored in batteries for later use.

   - Excess energy generated during the day can be stored for nighttime use.

3. **Radiative Cooling (Nighttime):**

   - At night, the radiative cooling process begins. Radiative cooling panels are designed with special materials that emit thermal infrared radiation efficiently.

   - These panels are designed to emit radiation in a wavelength range that corresponds to the "atmospheric window," allowing heat to escape into the cold of outer space without significant absorption by greenhouse gases in the Earth's atmosphere.

4. **Cooling Below Ambient Temperature (Nighttime):**

   - As the radiative cooling panels emit heat into space, they can cool down significantly below the ambient air temperature.

   - This cooling effect occurs because they lose heat to the cold night sky, which is colder than the panels themselves.

5. **Thermoelectric Conversion (Nighttime):**

   - Integrated within the radiative cooling panels are thermoelectric generators (TEGs).

   - TEGs utilize the temperature difference between the cooled panels and the night sky to generate electricity via the Seebeck effect.

   - When a temperature gradient exists across a TEG, it generates a voltage, and this voltage is used to produce electrical power.

6. **Continuous Power Generation (Nighttime):**

   - The radiative cooling process, coupled with TEGs, allows for continuous power generation throughout the night.

   - This continuous power output can be used to supply electricity during nighttime hours or whenever the radiative cooling effect is active.

7. **Energy Storage (Optional):**

   - To ensure a stable power supply, the electricity generated during the night can also be stored in batteries or other energy storage systems for use during periods of high demand or low radiative cooling.

In summary, a radiative cooling solar system combines the principles of traditional solar energy harvesting with night time radiative cooling and thermoelectric generation to produce electricity around the clock, extending renewable energy generation into the night.