Sun Geometry and Resources

Sun is source of almost all energy on our earth, either directly as a sunlight or indirectly as wind and wave. Sun is the endless source of energy. It is important to understand how solar PV system derive electricity from solar energy i.e., sunlight.

Solar panels use sunlight to generate electricity. We will discuss about working of solar technology in further topics but here we will discuss about terminologies related to solar which are responsible for energy generation in solar system.

Sun Angles

Solar angles refer to the position of the sun in the sky relative to an observer on the earth's surface. These angles are important in many applications, such as in solar energy systems, agriculture, and building design. The angle of the sun affects the amount of solar radiation received by a surface, which can impact the effectiveness of solar panels or the growth of plants.

The two most commonly used solar angles are the altitude angle, which measures the height of the sun above the horizon, and the azimuth angle, which measures the direction of the sun relative to true north. Together, these angles provide a complete description of the position of the sun in the sky at any given time and location.

Solar Altitude

Solar altitude is the measurement of the height of the sun in the sky, based on an observer's location. It is defined as the angle between the observer's horizon and the line connecting the observer to the sun. The solar altitude changes throughout the day, starting from zero at sunrise, reaching its highest point at solar noon (when the sun is at its highest), and ending at zero again at sunset.

Solar altitude is a key factor in designing a successful solar photovoltaic (PV) system. The altitude of the sun affects the amount of solar energy that is available at a given location and the angle at which the solar panels receive the sunlight.

To maximize energy production, the panels need to be angled correctly to receive the maximum amount of sunlight. This angle is dependent on the latitude of the location, as well as the time of year. The solar altitude can also be used to determine the shading effects on a solar panel throughout the day, which is important in ensuring that the panels receive consistent, unobstructed sunlight.

Solar Azimuth

Solar azimuth is the measurement of the position of the sun in the sky, based on an observer's location. The solar azimuth changes throughout the day, starting from -90° at due east in the morning (sunrise), reaching its highest point at 0° in noon (when the sun is at its highest), and ending 90° at due west in the evening (sunset).

Solar azimuth plays a crucial role in the design of a solar photovoltaic (PV) system as it determines the direction that the solar panels should face for maximum energy production. If the panels are facing in the wrong direction, they will receive less sunlight and produce less energy. The optimal orientation of solar panels is dependent on the latitude of the location, as well as the time of year.

By considering, solar azimuth and solar altitude in the design of a solar PV system, maximum energy production can be achieved, providing cost savings and a more sustainable source of energy.

Sun Path

The path of the sun refers to the movement of the sun across the sky throughout the day. The sun rises in the east, reaches its highest point in the sky at solar noon, and sets in the west. The exact path of the sun is dependent on the observer's latitude, as well as the time of year. At the equator, the sun rises vertically and moves directly overhead, while at higher latitudes, the sun rises at an angle and does not reach as high in the sky.

The sun's path is also affected by the tilt of the earth's axis, which results in the change of seasons. During the winter months in the northern hemisphere, the sun is low in the sky, while in the summer, it is high in the sky.

Understanding the path of the sun is important in many fields, including solar energy production, agriculture, and architecture. For example, in the design of a solar photovoltaic system, the path of the sun is used to determine the optimal orientation of the solar panels for maximum energy production.

Solar Radiation

Solar radiation is the energy that is emitted by the sun in the form of electromagnetic waves, including visible light, ultraviolet radiation, and infrared radiation. This radiation travels through space and reaches the Earth's atmosphere, where it is responsible for powering photosynthesis in plants, warming the planet, and providing the energy for all life on Earth.

The amount of solar radiation that reaches the Earth's surface also varies depending on factors such as the time of day, season, and location. For example, the amount of solar radiation that reaches the Earth's surface is greater near the equator than it is near the poles. Additionally, the Earth's atmosphere also plays a role in how much solar radiation reaches the surface, as some of the radiation is absorbed or scattered by gases and particles in the atmosphere.

Overall, solar radiation is an essential and powerful force in our solar system, and understanding how it interacts with the Earth is crucial for understanding and developing our solar system.

Insolation

Insolation is the amount of solar radiation that reaches the surface of the Earth. It is often measured in watts per square meter (W/m²) and is affected by factors such as the angle of the sun, cloud cover, seasons and atmospheric conditions.

In simple terms, insolation is incoming solar radiation.

Insolation varies depending on location. While designing a solar PV system, it is important to consider solar radiation characteristics for any location before the installation of the solar system. Solar PV system generation totally depends on the insolation received in that location. Insolation is important for understanding the potential for solar power generation.

PSH (Peak Sun Hours)

Peak sun hours refer to the number of hours during the day when the intensity of sunlight is at its highest. This usually occurs around solar noon, when the sun is directly overhead.

The number of peak sun hours varies depending on the location and time of year, with areas closer to the equator and during the summer months generally experiencing more peak sun hours than areas closer to the poles and during the winter months. It is important to note that the value of PSH is not a constant but changes with the season and location.

All these factors are important to consider when designing and optimizing solar energy systems, as they determine the amount of energy that can be captured by solar panels and the best orientation for the panels to face.

Conclusion

We have seen important parameters related to the Sun geometry and resources, which are crucial to consider when designing and optimizing solar photovoltaic (PV) systems. Now you are familiar with imporant geographical factors which are responsible for energy generation. In further topics, we will use these terms to understand and design our solar PV system.