Solar and Wind Power Awareness Series 3

——Off-Grid Solar Power Generation Design Solution

Solar energy is the most fundamental and essential source among various renewable energy options. Solar photovoltaic technology harnesses this energy by converting sunlight into electricity through specialized devices. Today, solar power generation stands out as one of the most convenient ways to produce electricity—simply because nearly every location on Earth receives ample solar radiation, and the process of harvesting it is remarkably straightforward. 。

A solar power unit is essentially a solar panel. (Also known as photovoltaic panels, solar modules) ) There are many types of solar panels, including crystalline silicon panels (monocrystalline and polycrystalline). , Amorphous silicon panels (such as cadmium telluride and gallium arsenide), perovskite solar cells, and more. Among these, crystalline silicon and amorphous silicon are already suitable for large-scale applications.

● How Photovoltaic Cells Work
　　 When light shines on the surface of a solar cell, some of the photons are absorbed by the silicon material. The energy from these photons is transferred to silicon atoms, causing electrons to jump to higher energy states and become free electrons. A potential difference is formed by the accumulation of charge carriers on either side of the P-N junction. When an external circuit is connected, this voltage drives a current through the circuit, generating useful output power. At its core, this process represents the conversion of photon energy into electrical energy.

● Off-grid solar power system

A system powered primarily by a solar power generation system—or one that prioritizes solar energy while relying on other energy sources for backup—is referred to as an off-grid solar power system. As for the so-called "Grid," here refers to the power grid.

The components of an off-grid solar power system primarily include solar panels, energy storage batteries, a solar charge and discharge controller, and an AC inverter, among others.

● Off-grid solar power system design Design of an Off-Grid Solar Power Generation System )

※ Steps for Off-Grid Solar Power Systems

First, Confirm the load's operating voltage, current, daily operating hours, maximum power, idle power consumption, and daily energy usage. (KWH). ( Table 1)

Second, Confirm the system installation location and, based on the specific site, verify the local solar daily irradiance. KWH/m² ）。 (Table II)

Note: Latitude and longitude lookup website: http://www.gpsspg.com/maps.htm

NASA solar irradiance query website: https://power.larc.nasa.gov/data-access-viewer/

Third, Based on the local solar irradiance and the load's daily power consumption, design and calculate the power rating of the solar panels. kWp ）。

Fourth, Based on the load's electricity usage patterns and characteristics, design the energy storage capacity of the battery system. Kilowatt-hour ) .

Fifth, Once the above design is completed, proceed to develop the installation process for solar panels, along with designs for battery storage cabinets or mounting structures, solar charge/discharge controllers and inverters, as well as DC and AC distribution cabinets, and system-level lightning protection measures tailored to the specific conditions of the installation site.

(To be continued)