TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred System: The system comprises: solar cell modules each having a different band gap; and step-up voltage transformers (boosters) that receive outputs from load resistors, the load resistors being controlled to maximize outputs of the respective solar cell modules, where an output current of each step-up voltage transformer (booster) is controlled to be a predetermined current value, and where the step-up voltage transformers (boosters) are connected in series to obtain predetermined electric power. The solar cell module includes one or more solar cells, the solar cells being monolithic series-connected solar cells, being integrated and controlled to obtain a predetermined output voltage value, and where each solar cell module is provided with a load resistor and a step-up voltage transformer (booster). The solar cell module includes one or more solar cells, the solar cells being monolithic series-connected solar cells, being integrated and controlled to obtain a predetermined output current value, and where each solar cell module is provided with a load resistor and a step-up voltage transformer (booster). The solar cell module includes one or more solar cells, the solar cells being monolithic series-connected solar cells, being integrated and controlled to obtain a predetermined output voltage value, and where each cell of each module is provided with a load resistor and a step-up voltage transformer (booster) formed in one piece with the cell. The solar cell module includes one or more solar cells, the solar cells being monolithic series-connected solar cells, being integrated and controlled to obtain a predetermined output current value, and where each cell of each module is provided with a load resistor and a step-up voltage transformer (booster) formed in one piece with the cell. It further comprises: step-down voltage transformers in addition to the load resistors and the step-up voltage transformers (boosters). It further comprises: step-down voltage transformer circuits in addition to the load resistors and the step-up voltage transformers (boosters). The solar cell modules are irradiated with collected light. The solar cell modules and the step-up voltage transformers (boosters) are disposed in a cooling device. It further comprises: a control device that feeds back the output voltage or output current of the step-up voltage transformer (boosters); and a communication device that conveys necessary information, where the step-up voltage transformer (booster) has a control function for controlling load impedance so as to maximize the output power of the solar cells. The solar cell modules and step-up voltage transformers (boosters) are placed in the cooling device, and where the cooling device includes a coolant in conduits and is provided with a radiator. Each solar cell module is compressed by an optically transparent insulator, and where the module, load resistor and step-up voltage transformers (boosters) are disposed on the insulator with wires. The solar cell module includes a p-n junction cell. The solar cell module includes silicon and silicon carbide. The solar cell module includes silicon and amorphous silicon. The solar cell module includes amorphous silicon and germanium. The solar cell module includes a dye-sensitized cell. Preferred Device: Alternatively, the photovoltaic power generation device comprises: solar cell modules each having a different band gap; load resistors that are controlled to maximize outputs of the respective solar cell modules; and step-up voltage transformers (boosters) that increase output voltages, where an output current of each step-up voltage transformer (booster) is controlled to be a predetermined current value, and where the step-up voltage transformers (boosters) are connected in series to obtain predetermined electric power. In the connection unit board for the solar cell module in a photovoltaic power generation device that includes load resistors that are controlled to maximize outputs of solar cell modules and step-up voltage transformers (boosters) that increase output voltages, an output current of each step-up voltage transformer (booster) being controlled to be a predetermined current value and the step-up voltage transformers (boosters) are connected in series to obtain predetermined electric power, the connection unit board for the solar cell module comprising at least two pairs of the load resistor and step-up voltage transformer (booster). It further comprises: a step-down voltage transformer in addition to the load resistor and the step-up voltage transformer (booster). It further comprises: a step-down voltage transformer in addition to the load resistor and the step-up voltage transformer (booster).