Fair power allocation in multi-user systems with controllable loads

Recent technology advancements make various renewable energy systems more available and easier to deploy, even in urban areas. Increasing penetration of renewable energy and government targets for even wider use of renewables require new control strategies and business models for RES integration. Also, due to less government incentives such as guaranteed feed-in rates, there is a need for algorithms facilitating local energy consumption. Though the concept of fairness in resource allocation has been investigated in other related fields such as computer science and network engineering, it is a new concern when sharing power from an intermittent energy supply. RES systems shared among multiple users can be easily envisioned in an era when all residential buildings are featured with rooftop mounted solar panels or when community electrical vehicle charging stations are powered by vertical axis wind turbines. The available energy might be often lower than demand, and it must be shared proportionally to user investments in the system, or according to restricted flat-rate contracts when the system is provided by a third-party. In this paper, we propose an on-line algorithm for power distribution that provides a proportional-share resource allocation. This optimization-based algorithm dynamically changes power rates allocated to different users depending on their previous energy consumption, their shares in the system and instantaneous power generation. We evaluate this approach on wind and solar-powered PHEV charging stations. Our simulation results show that enforcing proportional-share fairness among users does not decrease substantially the utilization of the available energy while achieving appropriate resource distribution, making this approach practical for use in a high variety of systems consisting of power loads with controllable consumption.