In some implementations, the power plant may include an array having 200 or more modules. In addition, the array may have conterminous modules. Arrays may include modules having a contact point that rests on the ground or a contact surface of one or more structures. In some implementations, 90% of the power-plant arrays have 800 or more modules. In some plants, the ground supports 90 percent of the conterminous modules. In some plants, neither the plants nor the arrays do not contain stowing functionality or extreme dampening functionality.

The invention discloses an islanding detection method in DC microgrids based on MPPT trapezoidal voltage disturbance. The steps are as follows: start the MPPT strategy; set the starting signal threshold of disturbance; measure the output current of PVA at the maximum power; calculate the same environmental factor of PVA with different capacities under the same light intensity and temperature in real time; when the environmental factor is greater than the starting signal threshold of the disturbance, periodic trapezoidal disturbance is carried out to the PVA port voltage reference; if the PCC voltage Upcc exceeds the threshold set by the passive method, it is judged as islanding; otherwise, it is judged whether the change rule of Upcc is consistent with the change rule of the calculated PCC voltage Upccp under the trapezoidal disturbance; If it is consistent, it is judged as islanding; otherwise, it is pseudo islanding.

The invention discloses an islanding detection method in DC microgrids based on MPPT trapezoidal voltage disturbance. The steps are as follows: start the MPPT strategy; set the starting signal threshold of disturbance; measure the output current of PVA at the maximum power; calculate the same environmental factor of PVA with different capacities under the same light intensity and temperature in real time; when the environmental factor is greater than the starting signal threshold of the disturbance, periodic trapezoidal disturbance is carried out to the PVA port voltage reference; if the PCC voltage Upcc exceeds the threshold set by the passive method, it is judged as islanding; otherwise, it is judged whether the change rule of Upcc is consistent with the change rule of the calculated PCC voltage Upccp under the trapezoidal disturbance; If it is consistent, it is judged as islanding; otherwise, it is pseudo islanding.

A solar powered charging station uses photovoltaic panels to generate electrical energy for use directly and/or for storage in electrical batteries for use during night operation. The station includes parallel electrical circuits which permit the station to operate during daylight hours in the event of a failure of the battery or the battery charging system. The station is adapted to use stabilizing ballast which can be collected locally at the site of the station. The parallel circuitry is adaptable for use with other forms of electrical power generation having a minimal carbon footprint.

A solar powered charging station uses photovoltaic panels to generate electrical energy for use directly and/or for storage in electrical batteries for use during night operation. The station includes parallel electrical circuits which permit the station to operate during daylight hours in the event of a failure of the battery or the battery charging system. The station is adapted to use stabilizing ballast which can be collected locally at the site of the station. The parallel circuitry is adaptable for use with other forms of electrical power generation having a minimal carbon footprint.

A low-voltage direct supply system capable of switching between solar energy and mains supply comprises: a solar and stable-voltage energy storage branch system used for providing solar power supply and charging through multiple groups of extensible solar panels and an energy storage battery pack; a mains power supply stable-switching branch system used for quickly switching to mains power supply without shocks through a mains supply conversion module and charging the energy storage battery pack; a power supply load detection and control branch system used for detecting a voltage, a charge/discharge current, and a balance between supply and demand of the energy storage battery pack and performing switching control on branch systems; and an output balance and low-voltage direct supply branch system used for performing balanced low-voltage direct supply on a load side according to a control output signal of the power supply load detection and control branch system.

A low-voltage direct supply system capable of switching between solar energy and mains supply comprises: a solar and stable-voltage energy storage branch system used for providing solar power supply and charging through multiple groups of extensible solar panels and an energy storage battery pack; a mains power supply stable-switching branch system used for quickly switching to mains power supply without shocks through a mains supply conversion module and charging the energy storage battery pack; a power supply load detection and control branch system used for detecting a voltage, a charge/discharge current, and a balance between supply and demand of the energy storage battery pack and performing switching control on branch systems; and an output balance and low-voltage direct supply branch system used for performing balanced low-voltage direct supply on a load side according to a control output signal of the power supply load detection and control branch system.

Various implementations power homes and businesses without needing to connect to electric utility company-provided power, i.e., they can operate off-grid. Generally the system includes solar panel racks (e.g., photovoltaic cells on sheets stabilized using ballasts, anchors, or mounting) that generate electrical power used to provide power to a building or that is stored on batteries. The system includes the solar panel racks and an enclosure to be installed at the premises and separate from the building. The enclosure includes the batteries and inverters that are electronically connected to the solar panel racks and batteries. The inverters are configured to convert direct current (DC) electricity from the solar power racks and batteries to alternating current (AC) electricity to provide power to the building via wires electrically connecting the inverters to the main panel of the building.

An integrated tandem solar cell includes a first solar cell including a rear electrode, a light absorption layer disposed on the rear electrode, and a buffer layer disposed on the light absorption layer; a recombination layer including a first transparent conductive layer disposed on the buffer layer; a nanoparticle layer that is transparent and conductive, that is disposed on the first transparent conductive layer, and that planarizes the first solar cell; and a second transparent conductive layer disposed on the nanoparticle layer; and a second solar cell that is a perovskite solar cell including a perovskite layer and that is disposed on and bonded to the second transparent conductive layer of the recombination layer. The recombination layer electrically joins the first and second solar cells and planarizes the first solar cell so that the second solar cell is uniformly deposited in all regions thereof.

A back contact structure of a solar cell, includes: a silicon substrate, the silicon substrate including a back surface including a plurality of recesses disposed at intervals; a plurality of first conductive regions and a plurality of second conductive regions disposed alternately in the plurality of recesses, where each first conductive region includes a first dielectric layer and a first doped region which are disposed successively in the plurality of recesses, and each second conductive region includes a second doped region; a second dielectric layer disposed between the plurality of first conductive regions and the plurality of second conductive regions; and a conductive layer disposed on the plurality of first conductive regions and the plurality of second conductive regions.