The working principle of solar lights – – VENTS Magazine – VENTS Magazine

Solar lights are electric lights that are converted into electrical energy by solar panels. In the daytime, even in cloudy days, this solar generator (solar panel) can also collect and store solar energy. As a new safe and environmentally friendly electric light, solar light has attracted more and more attention.

The solar light is composed of solar cell components, some LED lamps, a control box (with charger, controller, and storage battery in the control box) and a light pole. The luminous efficiency of the solar panel reaches 127Wp/m2, and the efficiency is high, which is very beneficial to the wind-resistant design of the system; the lamp holder part is integrated with 1W white LED and 1W yellow LED on the printed circuit board and arranged in a dot matrix with a certain interval as a plane. light source. The control box is made of stainless steel, which is beautiful and durable; the control box is equipped with a maintenance-free lead-acid battery and a special charge controller for solar street lights that has been successfully developed using patented slow pulse fast charge and discharge technology. The system uses valve-controlled sealed lead-acid batteries, which are also called “maintenance-free batteries” because they are rarely maintained, which helps reduce system maintenance costs; the charge and discharge controller is designed with full functions (with light control, Time control, overcharge protection, overdischarge protection and reverse connection protection, etc.) and cost control to achieve a very high cost performance.

The working principle of the solar lamp is simple. The solar cell is made by using the principle of photovoltaic effect. During the day, the solar cell panel receives solar radiation energy and converts it into electrical output. It is stored in the battery through the charge and discharge controller. At night, when the illumination is gradually reduced to about 101ux, The open circuit voltage of the solar panel is about 4.5V, and the charge and discharge controller will act after detecting this voltage value, and the battery will discharge the lamp cap. After the battery is discharged for 8.5 hours, the charging and discharging control action is performed, and the battery discharge is over. The main function of the charge and discharge controller is to protect the battery.

Solar energy is the energy produced by the continuous nuclear fusion reaction of sunspots inside or on the sun. The average solar radiation intensity in the earth’s orbit is 1367w/㎡. The circumference of the earth’s equator is 40,000 km, so it can be calculated that the energy obtained by the earth can reach 173,000 TW. The standard peak intensity at sea level is 1kw/㎡, and the average annual radiation intensity at a certain point on the earth’s surface for 24 hours is 0.20kw/㎡, which is equivalent to 102,000 TW of energy. Human beings rely on this energy to survive, including all other forms of energy. Renewable energy (except geothermal energy resources), although the total amount of solar energy resources is equivalent to more than 10,000 times the energy used by human beings, the energy density of solar energy is low, and it varies from place to place and changes with time. This is the development and utilization of solar energy. The main problem faced. These characteristics of solar energy will limit its role in the entire integrated energy system.

Although the energy radiated by the sun into the earth’s atmosphere is only one part of 2.2 billion of its total radiant energy, it is already as high as 173,000 TW, which means that the energy that the sun irradiates on the earth every second is equivalent to 5 million tons of coal. The earth’s wind energy, water energy, ocean temperature difference energy, wave energy and biomass energy, as well as part of the tidal energy all come from the sun; even the fossil fuels on the earth (such as coal, oil, natural gas, etc.) are fundamentally ancient Since the stored solar energy, the broad sense of solar energy includes a very large range, while the narrow sense of solar energy is limited to the direct conversion of solar radiant energy, photo-thermal, photoelectric, and photochemical.

Solar Energy (Solar Energy) generally refers to the radiant energy of sunlight, which is generally used to generate electricity in modern times. Since the formation of the earth, organisms have mainly survived by the heat and light provided by the sun, and since ancient times, humans have also known to use the sun to dry objects and use them as a method of preserving food, such as salt production and salted fish. However, with the reduction of fossil fuels, solar energy is deliberately developed further. There are two ways to use solar energy: passive utilization (photothermal conversion) and photoelectric conversion. Solar power is an emerging renewable energy source. In a broad sense, solar energy is the source of many energy on the earth, such as wind energy, chemical energy, potential energy of water, and so on.

As the earth’s resources become increasingly scarce, the investment cost of basic energy is increasing, and various safety and pollution hazards can be said to be ubiquitous. In this way, solar lighting products should emerge with the popularization of solar water heaters. Here we will make a practical comparison between the effects of solar lamps and the use of mains lamps.

*Compared with the complicated installation of mains lighting fixtures: In the mains lighting fixtures project, there are complicated operating procedures. First, cables must be laid, and a large number of basic works such as excavation of cable trenches, laying of concealed pipes, threading in pipes, backfilling, etc. . Then carry out a long-term installation and debugging, if any of the lines has a problem, a large area of ​​rework is required. In addition, the terrain and lines are complex, and the labor and auxiliary materials are costly. Solar lighting is easy to install: when solar lighting is installed, there is no need to lay complicated lines, just make a cement base and fix it with stainless steel screws.

* Comparison 2 High electricity costs for mains lighting fixtures: There are fixed and high electricity costs for mains lighting fixtures, and it is necessary to maintain or replace lines and other configurations for a long time, and the maintenance cost is increasing year by year. Solar lighting lamps are free of electricity charges: Solar lighting lamps are a one-time investment, without any maintenance cost, and the investment cost can be recovered in three years, and long-term benefits.

* Contrast three. Mains lighting has hidden safety hazards: Mains lighting has many hidden safety hazards due to construction quality, landscape lighting transformation, material aging, abnormal power supply, conflicts between water and electricity pipelines, etc. There is no hidden safety hazard in solar lighting: solar lamps are ultra-low voltage products, which are safe and reliable in operation.

Other advantages of solar lighting: green and environmental protection, it can add new selling points for the development and promotion of noble ecological communities; sustainable reduction of property management costs, and reduction of the owner’s public share of the cost. In summary, the inherent characteristics of solar lighting, such as safety, no hidden dangers, energy saving, no consumption, environmental protection, easy installation, automatic control and maintenance-free, will directly bring obvious advantages for real estate sales and municipal engineering construction.

Performance

The solar lights can be widely used in the decoration of grassland, square, park and other occasions, belonging to the technical field of lamps and lanterns. The lampshade is mainly used to connect the bottom bracket, the battery panel is placed on the battery box and built in the lampshade, the battery box is installed on the bottom bracket, the light-emitting diodes are installed on the battery panel, and the solar panel uses wires to connect the rechargeable battery and the control circuit. The structure of the utility model is integrated, simple, compact, and reasonable; no external power cord, easy to use and install, and beautiful in appearance; due to the use of light-emitting diodes in the bottom bracket, the entire lamp body is illuminated after light-emitting, and the light perception effect is better; All electrical components are built-in, which has good practicability. Including snake lights, panel lights, solar neon lights, massage lights, etc.

In practice, of course, solar outdoor lighting is a bit more complicated. In addition to large-capacity batteries and solar panels, the system also includes advanced dedicated monitors. When the lighting stops, the solar-powered battery starts to charge and then recharges fully to get more power. The key is that solar outdoor lighting and solar photovoltaic houses are equipped with solar panels, which have a dedicated microprocessor control system and battery. It is connected to a specially designed load lamp equipped with super reflectivity and high energy ballast. It has the advantages of high brightness, easy installation, reliable work, no cables, no consumption of conventional energy, and long service life. Using high-brightness LED light-emitting diode design, no manual operation is required, the lamps will automatically light up in dark, and automatically go out at dawn. The products have strong sense of fashion, bright texture, fineness, and modernity. They are mainly used in the lighting decoration of residential green belts, industrial park green belts, tourist scenic spots, parks, courtyards, square green spaces and other places.

Working principle

The solar power generation system is composed of solar battery packs, solar controllers, and storage batteries (groups). If the output power is AC 220V or 110V, an inverter is also required. The role of each part is:

Solar panel: The solar panel is the core part of the solar power system and the most valuable part of the solar power system. Its function is to convert the sun’s radiant power into electric energy, or send it to the storage battery for storage, or drive the load to work. The quality and cost of solar panels will directly determine the quality and cost of the entire system;

Solar controller: The function of the solar controller is to control the working status of the entire system, and to protect the battery from overcharging and over-discharging. In places with large temperature differences, a qualified controller should also have the function of temperature compensation. Other additional functions such as light control switch and time control switch should be optional options of the controller;

Batteries: generally lead-acid batteries, nickel-metal hydride batteries, nickel-cadmium batteries or lithium batteries can also be used in small and micro systems. Its function is to store the electrical energy generated by the solar panel when there is light, and then release it when needed.

Inverter: In many occasions, 220VAC, 110VAC AC power supply is required. Because the direct output of solar energy is generally 12VDC, 24VDC, 48VDC. In order to provide electrical energy to 220VAC electrical appliances, the DC power generated by the solar power generation system needs to be converted into AC power, so a DC-AC inverter is required. In some occasions, when multiple voltage loads are required, a DC-DC inverter is also used, such as converting 24VDC electric energy into 5VDC electric energy (note that it is not a simple step-down).

Influencing factors

The design of solar power system needs to consider the following factors:

Q1. Where is the solar power generation system used? What is the solar radiation situation in the area?

Q2. What is the load power of the system?

Q3. What is the output voltage of the system, DC or AC?

Q4. How many hours does the system need to work every day?

Q5. In case of rainy weather without sunlight, how many days does the system need to supply power continuously?

Q6. What is the starting current when the load is purely resistive, capacitive or inductive?

Q7. The number of system requirements.

Research direction

Solar power is not expensive. If the country is decisive and introduces an industrial policy that encourages the development of green energy, as technology advances, the cost of solar power generation will be further reduced. “His remarks aroused the reporter’s curiosity. The reporter interviewed many experts and asked them to discuss together: what should be done to make solar power as good as possible for mankind and the environment.

Industrial applications consume R&D costs. Ma Shenghong, a researcher at the Institute of Electrical Engineering of the Chinese Academy of Sciences, said that a new technology has different application requirements at different stages of development. Compared with other renewable energy power generation technologies, photovoltaic power generation has outstanding technical and economic advantages in solving the power supply of scattered villages, farmers and herdsmen in remote areas, and will play a major role in solving the power supply of China’s 30 million people away from the grid. In some special fields, photovoltaic power generation has risen rapidly. It has been shown in many fields, such as aerospace power supply, unmanned power supply for communication stations, pipeline cathodic protection, military field power supply, toys, clocks, street lights, courtyard lights, and emerging environmental protection buildings. “Comparative advantage.” Industrial applications can absorb a lot of research costs, and then promote the in-depth technical research, find more suitable materials and reduce cost solutions.

Source: https://ventsmagazine.com/2021/04/28/the-working-principle-of-solar-lights/

May 6, 2021 sally Wood