Off-grid Tiny House Smart Residential Energy Management System

Students at California State University (CSU), Chico designed, built, and tested an off-grid solar powered tiny house and competed in the 2016 Sacramento Municipal Utility District's (SMUD) Tiny House Competition. Top tier research institutions, predominantly undergraduate universities, and community colleges from all over California competed against one another in a variety of performance and aesthetic events in SMUD's first ever competition. One of the main goals of the CSU, Chico's Tiny House was to design and implement an autonomous energy management system to maximize energy capture, use, and efficiency and provide a seamless, comfortable, and uninterrupted indoor living environment. This system, smart residential energy management system (SREMS), was designed to monitor and sense solar energy collected and stored, indoor heating and cooling loads, occupant cooking and personal water heating needs, and electrical outlets and to determine and allow energy related activities given the amount of stored energy. Thermodynamic and heat transfer models were developed to predict heating, cooling, and appliance requirements. These models were used to size the solar array, battery storage, and appliances. SREMS was installed in the tiny house and its performance was tested and validated during the week long SMUD Tiny House competition. Results showed close correlation with the predicted energy requirements of the models, and the tiny house maintained net-zero energy use even during overcast and rainy skies throughout the three-day event. The CSU, Chico team won best control system and best technology at the statewide event. This paper describes the design, installation and testing results of CSU, Chico's Tiny House SREMS.