Energy-efficient management of eco-communities

With human environmental footprint exceeding the world´s regeneration capacity by about 30%, conserving energy and reducing emissions and waste are critical for sustainable living. A new prototype of living is eco-communities which consist of a set of buildings and associated devices for energy generation, conversion, consumption, storage and recovery networks trying to be self-sufficient as much as possible. The optimized operation of an eco-community, however, is challenging since multiple energy devices and energy processes are highly coupled; and the time coupling state dynamics in building models interact with each other in a complicated way due to the device coupling. This paper presents the integrated optimization of energy devices, energy processes, renewable energy and waste-to-energy conversion of a small eco-community to reduce daily costs while satisfying time-varying building needs. A mixed-integer optimization model of energy networks is established, and the problem is solved by using branch-and-cut. After linearizing all the nonlinear terms, near-optimal solutions are still difficult to obtain efficiently due to the complicated interactions among constraints. To improve the efficiency, a two-phase approach is developed. Numerical testing shows that the method can efficiently generate high quality operation schedules for the eco-community, and the total energy cost is reduced by this optimized operation, e.g., making efficient use of energy conversion and using the energy resources when they are cheap.