According to one embodiment, an electrical equipment housing includes a first storage room, an air conditioner, a second storage room, a temperature sensor, and a heater. The first storage room contains a power converter converting electrical power. The air conditioner adjusts a temperature inside the first storage room. The air conditioner includes an indoor unit and an outdoor unit. The indoor unit is provided inside the first storage room. The outdoor unit is provided outside the first storage room. The second storage room contains the outdoor unit. The temperature sensor senses a temperature inside the second storage room. The heater heats inside the second storage room when the temperature sensed by the temperature sensor is a lower limit or less.

Through a power cable from a power collection box, a power conversion device receives DC power. The power conversion device converts the received DC power into AC power and transmits it to a power system. A plurality of air lead-in tubes are laid in parallel. Each of the air lead-in tubes includes a heat exchange part, an opening part, and a lead-in part. The heat exchange part is buried in a ground at a ground surface on a back surface of a solar cell panel. The opening part is exposed to the ground surface. The lead-in part is an opening that communicates with an interior of a building in which the power conversion device is installed. The air lead-in tubes are constructed to draw air in the heat exchange part from the lead-in part by using a sucking mechanism.

A power electronics system comprising a environmentally sealed electronics compartment for housing power electronics equipment is provided. The system includes a plenum within the sealed electronic compartment for circulating air. A first liquid cooling loop is configured to cool air flowing through the plenum. A second liquid cooling loop configured to directly cool the power electronics equipment. The system includes a controller configured to independently control the flow rate of the first liquid cooling loop and the second liquid cooling loop.

A photovoltaic-inverter heat-dissipation assembly is disclosure and includes a front housing-base, a rear cover, a first heat-generating device, a first fan, a second heat-generating device and a second fan. The rear cover and the front housing-base are combined to separately form a first heat-dissipation space and a second heat-dissipation space. The rear cover includes a first air-inlet, a second air-inlet and an air-outlet. The first air-inlet and the second air-inlet are in communication with the air-outlet through the first heat-dissipation space and the second heat-dissipation space, respectively. The first fan generates a first airflow, which enters through the first air-inlet, flows through the first heating-generating device accommodated in the first heat-dissipation space, and flows out through the air-outlet. The second fan generates a second airflow, which enters through the second air-inlet, flows through the second heat-generating device accommodated in the second heat-dissipation space, and flows out through the air-outlet.