Proposal of a nearly zero energy building electrical power generator with an optimal temporary generation–consumption correlation

• We developed an electrical system for Solar Decathlon Europe 2012.
• A mixed AC–DC coupling system for an electrical grid-tie installation.
• We analyzed self-sufficiency systems for nZEBs with low capacity batteries.
• Appropriate active demand-side management saves electrical energy.

This study presents an electrical photovoltaic (PV) power generator system, which was designed, built, and tested during the Solar Decathlon Europe 2012 competition as part of the SMLsystem, i.e., the CEU Cardenal Herrera University prototype. One of the main aims of the contest was to evaluate the prototype's electrical energy balance capacity in terms of self-sufficiency, low energy consumption, and the temporary generation–consumption correlation demand. The design and evaluation were determined according to the competition rules and a framework was built for a type of nearly zero energy building (nZEB), where the specific criteria required that all the necessary energy was obtained from the sun. Various aspects were considered in the design of the PV system, including the energy demand and disposability, possibility of grid connection, power installation, appropriate battery capacity, electrical PV system configuration (AC coupling and/or DC coupling), and the temporary generation–consumption correlation demand. To achieve an optimal energy balance, the electrical PV power generator system design strategy focused on the energy correlation analysis behavior and the efficient management of the energy system, while maintaining the main load of the nZEB at a sufficiently low level using a timed controller.