Optimization of the Hybrid Energy Harvest Systems Sizing for Net-Zero Site-Energy Houses

Abstract

Energy-efficient and net-zero-energy buildings are quickly gaining importance and popularity among contemporary building practices. Typically, several renewable energy–harvesting systems are combined to reach the objective of net-zero energy consumption, posing the unique challenge of properly sizing each energy system. Because no standard design procedure exists, installed energy systems often are inappropriately sized. In this paper, we propose a holistic design procedure to determine and optimize the corresponding size of renewable energy systems in a typical residential house to meet the total energy demand. To evaluate this procedure, a case study was implemented for the zero net energy test house at the University of Nebraska that uses three energy-source systems: geothermal, photovoltaic panel, and wind turbine. Although the results of the case study indicate that, based on present costs of renewable-energy sources, energy systems are more expensive to operate in a zero-energy house than in homes using grid power, the proposed size-optimization method for the renewable energy sources was found to be sound.