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Lee, Russell

Publications and source records attributed to Lee, Russell.

Online peak-aware energy scheduling with untrusted advice

This paper studies the online energy scheduling problem in a hybrid model where the cost of energy is proportional to both the volume and peak usage, and where energy can be either locally generated or drawn from the grid. Inspired by recent advances in online algorithms with Machine Learned (ML) advice, we develop parameterized deterministic and randomized algorithms for this problem such that the level of reliance on the advice can be adjusted by a trust parameter. We then analyze the performance of the proposed algorithms using two performance metrics: robustness that measures the competitive ratio as a function of the trust parameter when the advice is inaccurate, and consistency for competitive ratio when the advice is accurate. Since the competitive ratio is analyzed in two different regimes, we further investigate the Pareto optimality of the proposed algorithms. Our results show that the proposed deterministic algorithm is Pareto-optimal, in the sense that no other online deterministic algorithms can dominate the robustness and consistency of our algorithm. Furthermore, we show that the proposed randomized algorithm dominates the Pareto-optimal deterministic algorithm. Our large-scale empirical evaluations using real traces of energy demand, energy prices, and renewable energy generations highlight that the proposed algorithms outperform worst-case optimized algorithms and fully data-driven algorithms.

Lee, Russell↗

Eastern Interconnection Demand Response Potential

Demand response (DR), one of the key components in the Smart Grid initiative, has received increasing interest in recent years among power utilities, independent system operators, and policy makers. With this surge of interest in DR, in April 2010 the Department of Energy (DOE) issued a research call to provide technical support to the interconnection-level electric infrastructure planning projects they had issued earlier in the year. In Area of Interest 2, they identified a need/purpose: “The Eastern Interconnection States’ Planning Council (EISPC) seeks to significantly improve the knowledge base and modeling capabilities of demand-side resources for purposes of transmission planning.” In response to the research call, Oak Ridge National Laboratory (ORNL) conducted a research project to estimate the DR potential peak load reductions in the Eastern Interconnection area over the next two decades until 2030, as well as analyzed costs and benefits occurring out of the DR resources. This final report is the outcome of the study by a team of ORNL researchers with diverse backgrounds in engineering, economics, and public policy.

demand response↗

Jupiter, Tether, and Lenz's Law

Jupiter has a large, complex, and intense magnetic field that is thought to arise from electrical currents in the rapidly spinning metallic hydrogen interior. The strong magnetic field can induce currents when the conductive tether is directed toward or away from Jupiter. The currents can be stored and used for both propulsion and power generation. Therefore, our spacecraft might be able to visit several Jovian moons or maintain in the orbit around Jupiter. In our future space traveling, we also can use this technical skill to travel to other planets without any fuel. First-year physics textbooks describe Lenz's Law in which current is induced in a conductor moving through a stationary magnetic field. A demonstration of induced current in a stationary conductor and moving magnetic field is described, which may have space-tether application.

Lee, Russell↗