Advantages and disadvantages of installing solar panels on the roof

The solar roof is to install solar power generation devices on the top of the house, and use solar photovoltaic technology to generate electricity in the field of urban and rural buildings to achieve the goal of energy saving and emission reduction. In order to implement China's energy-saving and emission-reduction targets promised to the world and strengthen policy support for the new energy economy strategy, relevant national ministries and commissions have launched a solar roof plan.
Housing or office roofs used to install photovoltaic solar panels have the following advantages
　　 1. It is usually easy to receive solar energy
　　2. Installing a photovoltaic array on the roof allows you to use the otherwise useless space and save the yard space.
　　 3. It is very close to the existing power system, which helps to reduce the overall cost.
　　4. The device installed on the roof has the least impact on the site
　　Of course, the roof is not always the absolute best location for the photovoltaic array. Placing the photovoltaic array on the roof of the building also has the following disadvantages.
　　 1. The orientation of the square is dominated by the building
　　2. Because it is close to the roof, photovoltaic modules run at a higher temperature (therefore lower efficiency)
　　3, the amount of square lineup is limited by the available area
　　4. When the roof needs to be renovated, the phalanx also needs to be removed (the roof was in good condition at the beginning, so this situation will not happen until 15 years later)
　　 5. The phalanx may not be easy to approach, in this case the ice and snow on the phalanx cannot be removed
　　6. ​​Penetrating the roof (perforating holes is required when fixing the phalanx on the roof), which may lead to roof leakage.
Solar power system composition
　　 is composed of solar battery pack, solar controller and storage battery (group). If the output power is AC 220V or 110V, an inverter is also required. The role of each part is:
　　 (1) Solar panels: Solar panels are 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 radiation capacity 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.
　　 (2) Solar controller: The function of the solar controller is to control the working status of the entire system, and to protect the battery from overcharge and over discharge. 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.
　　 (3) Storage batteries: generally lead-acid batteries, in small and micro systems, nickel-hydrogen batteries, nickel-cadmium batteries or lithium batteries can also be used. Its function is to store the electric energy generated by the solar panel when there is light, and then release it when needed.
　　 (4) 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.
　　Although there are disadvantages, in many cases, the roof may be the only option for installing solar panels. Many household photovoltaic power generation systems choose to be built on the roof, which is the best example.