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Reveal Unbeknown Details for Small Solar Power System

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Small solar power system comprises of solar panel, battery and PV controller. Inverter should be allocated if output is AC110V-220V. It is mostly used for home illumination and outdoor camping.
Principle of Power Generation.
Sunlight radiates on the P-N junction of semiconductor, to form new electron hole pair, under the electric field of P-N junction, electric hole flow from N field to P field, it would have Current after circuit conduction. This is the working principle of PV solar cells.

There are two types for solar power generation, one is to convert from sunlight to heat to electric power, another is to convert from sunlight to electric power.
1) This type of sunlight to heat to electric power is through adopting the heat which is produced by solar radiation to generate power, usually it is via solar collector to convert the heat into industrial vapor, the vapor drive steam turbine to generate. The first process is to convert solar power into heat, the second process is to convert heat into electric power.

2) The type of sunlight to electric power is to utilize Photovoltaic effect to directly convert solar power into electric power, the basic equipment of sunlight to electric power is solar cells. Solar cells is the device which is getting through Photovoltaic effect to convert sunlight into electric power, it is semiconductor photoelectricity diode, when sunlight radiates on photoelectricity diode, the diode would convert sunlight into electric power, to produce current.


The Function of Each Component.
1. Solar Panel.
Solar panel is the core component of small solar power system, it is also the highest value of solar system. Its function is to convert solar radiation into electric power, the electric power would be transmitted into battery or provide power supply for loads.
2. Solar Controller.
The function of solar controller is to control the working state of whole system and to prevent battery from over-charge or over-discharge. Under big temperature difference circumstance, qualified controller should have temperature compensation function. Other additional function, such as light-operated power switch, time-control power switch, should be option for controller.
3. Storage Battery.
There are many types of battery, such as Lead-acid battery, Ni-MH battery, Ni-Cd battery and Lithium battery. Its function is to store electric power which is generated by solar panel, the electric power would be discharged when loads require.
4. Inverter.
Usually, the output of solar panel is DC12V, DC24V and DC48V. In order to provide power supply for AC110V-220V appliances, the DC electric power should be transformed into AC, then the Inverter is necessary to transform the power.

Categories.
Home solar power system can be classified as off-grid PV generation and on-grid PV generation.
1. Off-grid solar PV system need battery to store electric power, solar panel can generate only if having sunlight, the battery would discharge to provide power supply when it is in need.

2. On-grid solar PV system is the current which is converted by solar power to get through on-grid inverter to transform into the AC power which accords with grid power, the AC power directly connect with State Grid.
On-grid solar PV system can be classified as centralization large-scale on-grid solar power station and distributed-grid small solar power generation system. Centralization large-scale solar system is State Power Station, its main characteristic is directly to transmit electric power into Grid Power, the grid power would distribute to users. This station need occupy large-scale area, long periodical establishment, big investment, it is relative hard to develop. While distributed-grid small solar PV generation system, especially for Building Integrated Photovoltaic solar system, is the mainstream of on-grid solar system because of these advantages of small investment, fast establishment, small land area occupation and government policies support, etc.


System Allocation Factors.
Many factors should be considered when it is required to design small solar power system.
1. Where does the solar system be used ? How is the local daily solar radiation ?
2. What total power is for loads ?
3. What output voltage is for the system ? is it DC or AC ?
4. How many hours is required to work for the system ?
5. How many days is required to continue to provide power supply for the system if it is rain.
6. The loads situation, pure resistance, pure capacitive or inductive, what is starting Current ?

As the detail description for small solar power system, more and more users would know the reason why it is popularly welcome in market. Because it can be standalone, convenient to use, easy to take and install, which has provide portability, it is widely applied for remote area, travel, camping and night market, etc.