In residential applications, an air-to-water CO2 heat pump is used in combination with a domestic hot water storage tank, and the performance of this system is affected significantly not only by instantaneous ambient air and city water temperatures but also by hourly changes of domestic hot...

When evaluating residential energy systems like co-generation systems, hot water and electricity demand profiles are critical. In this paper, the authors aim to extract basic time-series demand patterns from two kinds of measured demand (electricity and domestic hot water), and also aim to...

The impact of the sampling time interval for energy demands on the optimal operational planning of residential cogeneration systems without electric power export was analyzed. To improve their operational flexibility, focus was also placed on battery installation. First, an optimal operational...

This study develops a wind speed sensorless performance monitoring method for stand-alone vertical axis wind turbines, by means of a numerical analysis using a dynamic simulation model. The method focuses on improvements in the response speed of the rotor with deterioration in wind turbine...

The feasibility on a residential energy supply network using multiple cogeneration systems, known as combined heat and powers, is investigated by an optimization approach. The target residential energy supply network is based on a microgrid of residential cogeneration systems without electric...

An optimal structural design model of a residential cogeneration system, known as combined heat and power, considering various kinds of operating restrictions is developed from the energy-saving viewpoint. As principal operating restrictions of cogeneration units, a constant power output...

Air-to-water heat pumps using CO2 as a natural refrigerant have been developed and commercialized. They are expected to contribute to energy saving in residential hot water supply. The objective of the research is to analyze the performance of a water heating system composed of a CO2 heat pump...

The effect of power interchange operation of multiple household gas engine cogeneration systems (H-GCGS) on the energy-saving is investigated using an optimization approach based on the mixed-integer linear programming. In this power interchange operation, electricity generated by H-GCGS is...

A suitable operational strategy for a power interchange operation using multiple residential solid oxide fuel cell (SOFC) cogeneration systems for saving energy is investigated by an optimization approach based on mixed-integer linear programming. In this power interchange operation, electricity...

A power interchange operation, in which electric power generated by multiple residential solid oxide fuel cell cogeneration systems (R-FCGSs) is shared among residences in a housing complex with no reverse power flow to a commercial electric power system, has a high energy-saving effect as...