2022年家庭储能行业研究报告

家庭储能通常与户用光伏配合使用，装机量迎来高速增长。家庭储能系统，又称电池储能系统，其核心是可充电的储能蓄电池，通常以锂离子或铅酸电池为基础，由计算机控制，在其他智能硬 件及软件的协调下实现充电和放电循环。家庭储能系统通常可与分布式光伏发电相结合形成家庭光储系统。从用户侧来看，家庭光储系统在降低电费的同时，可以消除停电对正常生活的不良影响；从电网侧来看，支持统一调度的家庭储能设备可以缓解高峰时段的用电紧张并为电网提供频率修正。

根据光伏和储能系统的耦合方式的不同，分为直流耦合系统和交流耦合系统，分别适合与新装光伏系统的增量市场和已装光伏系统的存量市场。增量市场空间更大，是未来市场增长的主要动力：

（1） 增量市场（目标家庭新安装光伏+储能系统）：一般使用直流耦合产品。直流耦合的储能系统包含电池系统和混合逆变器，混合逆变器兼具了光伏并网逆变器和储能变流器的功能。直流耦合的优势在于，光伏和储能电池都通过混合逆变器完成变流，不需要额外安装光伏并网逆变器，系统集成度更高，安装和售后服务都更方便，同时便于智能监测和控制。有部分已经安装好光伏系统的家庭选择拆除原有的光伏并网逆变器，新安装混合逆变器。

（2） 存量市场（目标家庭已安装光伏，新增储能系统），一般使用交流耦合产品。只需加装蓄电池和储能变流器，不影响原来的光伏系统，而且储能系统的设计原则上和光伏系统没有直接关系，可以根据需求来定。交流耦合的优势在于高安全：交流耦合方式下，能量汇集于交流端，既可以直接提供给负载使用或者送入电网，也可以通过双向变流器直接向蓄电池充电，可以选用低压 PV 和低压电池，消除储能系统中的直流高压风险。

根据系统是否并入电网，家庭储能系统可以分为并网系统和离网系统，核心差异在于是否接入电网，目前多数区域使用的是并离网一体机系统。（1）并网系统，光伏和储能系统可以接入电网，在光伏或电池的电量不足时可以从电网购电。适合电力系统稳定、电价相对较低的区域。（2） 离网系统，适合于没有电网的沙漠、海岛等地区或者电网不稳定需要自发自用的区域。使用离网储能变流器，通常具备柴油发电机接口，在夜间电池供电不足时补充电力。（3）并离网一体机，具有并离网切换功能或者将并网、离网模式整合在一台机器中，可以在停电时完成切换进入离网模式，适合电力系统不稳定、经常停电的地区。

Household energy storage is usually used in conjunction with household photovoltaic, and the installed volume has ushered in a rapid growth. The core of home energy storage system, also known as battery energy storage system, is a rechargeable storage battery, usually based on lithium-ion or lead-acid batteries, controlled by a computer, under the coordination of other intelligent hardware and software to achieve charging and discharging cycle. Home energy storage system can be combined with distributed photovoltaic power generation to form a home optical storage system. From the user side, the home optical storage system can not only reduce the electricity cost, but also eliminate the negative impact of power failure on normal life. From the grid side, home energy storage devices that support unified scheduling can alleviate peak hours and provide frequency correction for the grid.

According to the different coupling modes of photovoltaic and energy storage systems, they are divided into DC coupling system and AC coupling system, which are suitable for the incremental market of newly installed photovoltaic systems and the stock market of installed photovoltaic systems respectively. Larger incremental market space is the main driving force for future market growth:

(1) Incremental market (newly installed PV + energy storage system in target households) : DC coupling products are generally used. The DC coupled energy storage system consists of a battery system and a hybrid inverter, which has the functions of photovoltaic grid-connected inverter and energy storage converter. The advantage of DC coupling lies in that both photovoltaic and energy storage batteries are converted through hybrid inverters, which does not require additional installation of photovoltaic grid-connected inverters. The system is more integrated, convenient for installation and after-sales service, and convenient for intelligent monitoring and control. Some households that have installed PV systems choose to remove the original PV grid-connected inverter and install a new hybrid inverter.

(2) Stock market (target households have installed PV and newly added energy storage system), AC coupling products are generally used. Only need to install battery and energy storage converter, does not affect the original photovoltaic system, and the design of energy storage system in principle and photovoltaic system has no direct relationship, can be determined according to demand. The advantage of AC coupling lies in high safety: In AC coupling mode, energy is collected at the AC end, which can be directly supplied to the load or sent to the power grid, or directly charged to the battery through the two-way converter. Low-voltage PV and low-voltage batteries can be used to eliminate the risk of DC high voltage in the energy storage system.

According to whether the system is integrated into the power grid or not, the home energy storage system can be divided into grid-connected system and off-grid system. The core difference lies in whether the system is connected to the power grid or not. At present, most regions use the off-grid all-in-one system. (1) Grid-connected system: photovoltaic and energy storage systems can be connected to the power grid, and electricity can be purchased from the power grid when photovoltaic or battery power is insufficient. Suitable for stable power system, relatively low electricity price area. (2) Off-grid system, suitable for desert, island and other areas without power grid or unstable power grid need to spontaneous self-use. Use off-grid energy storage converters, usually with diesel-generator interfaces, to replenish power at night when battery power is low. (3) Off-grid integrated machine, with off-grid switching function or the integration of grid-connected and off-grid modes in one machine, can complete the switch to off-grid mode in the case of power failure, suitable for unstable power system, frequent power failure areas.

Household energy storage is usually used in conjunction with household photovoltaic, and the installed volume has ushered in a rapid growth. The core of home energy storage system, also known as battery energy storage system, is a rechargeable storage battery, usually based on lithium-ion or lead-acid batteries, controlled by a computer, under the coordination of other intelligent hardware and software to achieve charging and discharging cycle. Home energy storage system can be combined with distributed photovoltaic power generation to form a home optical storage system. From the user side, the home optical storage system can not only reduce the electricity cost, but also eliminate the negative impact of power failure on normal life. From the grid side, home energy storage devices that support unified scheduling can alleviate peak hours and provide frequency correction for the grid.

According to the different coupling modes of photovoltaic and energy storage systems, they are divided into DC coupling system and AC coupling system, which are suitable for the incremental market of newly installed photovoltaic systems and the stock market of installed photovoltaic systems respectively. Larger incremental market space is the main driving force for future market growth:

(1) Incremental market (newly installed PV + energy storage system in target households) : DC coupling products are generally used. The DC coupled energy storage system consists of a battery system and a hybrid inverter, which has the functions of photovoltaic grid-connected inverter and energy storage converter. The advantage of DC coupling lies in that both photovoltaic and energy storage batteries are converted through hybrid inverters, which does not require additional installation of photovoltaic grid-connected inverters. The system is more integrated, convenient for installation and after-sales service, and convenient for intelligent monitoring and control. Some households that have installed PV systems choose to remove the original PV grid-connected inverter and install a new hybrid inverter.

(2) Stock market (target households have installed PV and newly added energy storage system), AC coupling products are generally used. Only need to install battery and energy storage converter, does not affect the original photovoltaic system, and the design of energy storage system in principle and photovoltaic system has no direct relationship, can be determined according to demand. The advantage of AC coupling lies in high safety: In AC coupling mode, energy is collected at the AC end, which can be directly supplied to the load or sent to the power grid, or directly charged to the battery through the two-way converter. Low-voltage PV and low-voltage batteries can be used to eliminate the risk of DC high voltage in the energy storage system.

According to whether the system is integrated into the power grid or not, the home energy storage system can be divided into grid-connected system and off-grid system. The core difference lies in whether the system is connected to the power grid or not. At present, most regions use the off-grid all-in-one system. (1) Grid-connected system: photovoltaic and energy storage systems can be connected to the power grid, and electricity can be purchased from the power grid when photovoltaic or battery power is insufficient. Suitable for stable power system, relatively low electricity price area. (2) Off-grid system, suitable for desert, island and other areas without power grid or unstable power grid need to spontaneous self-use. Use off-grid energy storage converters, usually with diesel-generator interfaces, to replenish power at night when battery power is low. (3) Off-grid integrated machine, with off-grid switching function or the integration of grid-connected and off-grid modes in one machine, can complete the switch to off-grid mode in the case of power failure, suitable for unstable power system, frequent power failure areas.