System controls for solar-heating and heat- and cool-storage systems. Final report

This summary report describes control strategies for residential solar heating systems and off-peak heat and cool storage systems. Research was conducted to provide utilities with quantitative data to assess the impacts of these energy systems. Control strategies for selected reference residential energy systems were defined and optimized with respect to 1990 and 2000 owner and utility costs. Computer simulations were used to model the performance of optimal and suboptimal controllers applied to an off-peak storage system, a solar heating system, and a combined system. Each was modeled and compared to a baseline all-electric system using data for nine utility service areas. Other work included investigating the benefits of incorporating weather prediction into control systems, development of a mathematical model for predicting the performance of a passive solar dwelling, definition of controller requirements and specifications, outlining a test plan for the preferred control system, and development of a simplified mathematical methodology for analysis of residential HVAC systems and their utility interactions. The study found that an off-peak storage system using proportional control was the least-cost system. Recommended energy storage discharge strategies are: proportional control for either off-peak or solar storage during the heating season; weighted proportional for cooling season off-peak storage;more » and proportional discharge from December through February for combined systems, with conventional discharge for the remainder of the year. The comparative characteristics of the control strategies were fundamentally the same in all areas of the country.« less