Solar energy options for self-driving tours

Many car friends have discussed that they are considering installing solar panels to solve the problem of electricity consumption when traveling by car. Let's discuss this topic together.

1. Advantages.
The advantages of installing solar panels are obtained from the comparison with generators.
1. Simple installation and low initial investment.
The current solar panels are very simple to install. If there is a ready-made auxiliary battery, the cost can be done with a few hundred yuan. Two 100W-150W monocrystalline panels, ranging from 400 yuan to 600 yuan, plus a charging controller, you can make a rack yourself.
2. Environmentally friendly and pollution-free, protecting the battery from power loss.
Wherever there is sunshine, there can be electricity generation, which is inexhaustible. Using solar panels will not pollute and damage the environment, which is incomparable to generators. Solar panels can easily charge spare batteries and extend the service life of batteries.
3. One-time investment is maintenance-free, saving worry and effort.
Solar panels not only have a low initial cost, but also are maintenance-free and can be used reliably for a long time. Generators need fuel to work, and the fuel cost is not low. At the same time, lubricants need to be added, and the maintenance cost is relatively high. Therefore, solar panels are easier to use than generators.
4. More convenient to use.
Generators are divided into self-contained generators and vehicle-mounted generators. Refueling a self-contained generator is a problem, and gas stations may not refuel; vehicle-mounted generators are fixed on the chassis, and will cause resonance in the car when started, making noise, so solar panels are more convenient to use.

2. Disadvantages.
1. There will be wind resistance and increase fuel consumption.
Solar panels occupy a large space and are generally placed on the top of the car body. During driving, wind resistance will inevitably increase, resulting in increased fuel consumption. If calculated based on an increase of 1 liter of fuel consumption per 100 kilometers, solar panels cannot generate 1 kWh of electricity a day, which is not as good as using a generator to generate more electricity with 1 liter of oil, so it is not cost-effective.
2. The actual use is far from expected.
Many car owners complained that the power generation was too low after installing solar panels. The efficiency of solar panels is not high. It is difficult for us to achieve the ideal use requirements in daily life. For example:
(1) The surface of the solar panel must be kept clean. If there is dust, it will affect the effect. Air pollution will also have an impact.
(2) The light-receiving surface of the solar panel must be directly exposed to the sunlight at 90 degrees to achieve the best effect. This is difficult to achieve on the car.
(3) Under normal circumstances, the lighting conditions that meet the rated power of the solar panel cannot be achieved. It is only possible to approach it at noon on the plateau.
3. It will cause great damage to the car body and damage the car paint.
The temperature under the solar panel is generally high during operation. If the distance between the solar panel and the car body is close or the ventilation is poor, the paint surface of the car body will be burned over time. Especially for the flexible solar panel attached to the car body, the damage to the car body is more obvious. If it is removed when not in use, the car body will be scarred.

4. Low efficiency and low conversion rate;
The efficiency of solar panels is low. The most practical polycrystalline silicon panel has a power of about 100W per square meter. The current most efficient solar panel has a conversion rate of only about 20%.
For example, the surface area of ​​the solar panel on the roof of the car is 2 square meters. According to the best power of 500W/square meter, the average sunshine time is 5 hours, and about 1 kWh of electricity can be obtained every day. This is calculated according to the highest standard. In fact, the solar panel has half of the irradiation area, so only 0.5 kWh of electricity is obtained every day.
5. Unstable, low cost-effectiveness.
The solar panel must be connected to the auxiliary battery for use. It is not advisable to connect the electrical appliance directly from the controller. In theory, as long as the voltage and current match, it can be directly connected to the DC electrical appliance. But in fact, solar power generation is affected by factors such as sunlight intensity and ambient temperature, and the output current and voltage are unstable. If connected directly, it will seriously affect the service life of the electrical appliance, and the use of electricity is not safe.
The advantages we mentioned above are all without considering the auxiliary battery. The cost of solar cells is relatively expensive, with a power of 180W per square meter, a weight of 4 kilograms, and a price of 1,200 yuan. The whole vehicle is 2 square meters, which requires 2,400 yuan, and at the same time increases the weight of the vehicle by more than 8 kilograms. It is better to buy a lead-acid battery, which is cost-effective and has a low cost-effectiveness.

3. How to choose?
1. Solar panels can only be used as auxiliary charging equipment, not as the main power supply method. If other charging methods have been implemented and the electricity is still not enough, you can consider solar panels, which is also a solution after no other way.
2. The area on the roof of the RV is large, so it can be considered. For ordinary bed cars, it is very good to have a roof of 2 square meters, so you can give up directly.
3. There are now intelligent retractable solar panels on the market, which have a large enough area to receive solar energy. When not in use, the solar panels can be retracted. When in use, the area can be remotely enlarged by more than 2 times, which is more convenient for parking.
4. The difference between flexible thin-film solar panels and conventional solar panels.
Conventional solar panels are heavy and require brackets when installed, which are not easy to move. Flexible thin-film solar panels are 80% lighter than conventional solar panels, and can even be bent arbitrarily, which is convenient to carry and has a wide range of uses.
Conventional solar panels have high conversion efficiency, while flexible thin-film solar panels have relatively low conversion efficiency.