Ph.D. Candidate. Thesis topic: The value of reliability for microgrids: Modeling interactions of technology choice, reliability and economics. Expected graduation: Fall 2017.
Research and project advisors:
Prof. Jan Kleissl (co-PI)
Department of Mechanical and Aerospace Engineering
Associate Director, Center for Energy Research
University of California, San Diego
Prof. David Victor (co-PI)
School of Global Policy and Strategy
Director, Laboratory on International Law and Regulation
University of California, San Diego
Center for Energy Research
Program Director of Energy Storage Systems
University of California, San Diego
My research has spanned several topics and projects over 5+ years at UC San Diego. The consistent, core focus, though, has been modeling, optimization and simulation of distributed energy resources—in particular in the microgrid framework. I include below brief summaries of research.
Modeling microgrid reliability and emissions. Many observers believe the future electric grid will be low-carbon and perhaps decentralized. Microgrids may be a key enabler. In this work, I have built an optimization model for microgrids that sizes and schedules resources in the microgrid and that considers revenue streams from providing energy (power, heat, cooling) locally as well as from improving electric service reliability for customers within. We have studied why and how customers of different classes invest in, and benefit from, microgrids that improve reliability. We have also looked at policy aspects around emissions—specifically, how customer microgrids impact greenhouse gas emissions from the electric power sector.
Microgrid business cases. Stand-alone distributed generation (e.g. solar PV, electric energy storage, CHP, thermal storage) and microgrids (which control combinations of these technologies) may shape a future decentralized electric grid. This work investigates the extent to which a decentralized paradigm can help decarbonize the grid, and in what ways that paradigm is optimal (or not). Regulations that will shape the future power system are far from certain, however—and that uncertainty affects the business cases for microgrids today. We are modeling policy, technology and market variables to understand how they affect the economics feasibility, or “business case”, for microgrids. These factors have real consequences, for policy or otherwise—e.g. they may push (or not) least-cost investment toward renewables.
Grid integration of solar energy. Solar PV power output is inherently intermittent. When adopted in high penetrations, that intermittency can degrade local power quality and cause voltage excursions or substation back-flow. In this research, we modeled five utility feeders using the distribution system simulator OpenDSS to explore the grid impacts of distributed and centralized PV at increasing penetration levels.
Customer applications for solar+storage systems. Numerous uses for solar PV+battery energy storage (“solar+storage”) systems sited behind-the-meter have been proposed and studied—e.g., load shifting, peak load shaving, PV ramp rate control, and microgrid applications. At UC San Diego, we have developed optimization algorithms for peak load shaving and PV ramp rate control using a solar+storage system. These algorithms have been simulated in the virtual environment and implemented operationally using real PV systems and second-life EV battery storage systems at the UC San Diego campus.
- R. Hanna, J. Kleissl, D.G. Victor, “Greenhouse gas emission impacts of private microgrids in California,” (working paper).
- R. Hanna, V. Disfani, J. Kleissl, D.G. Victor, “The economic value of reliability for microgrids: Modeling reliability costs and value,” (working paper).
- R. Hanna, V. Disfani, J. Kleissl, “Reliability evaluation for microgrids using cross-entropy Monte Carlo simulation,” Probabilistic Methods Applied to Power Systems (PMAPS) 2018, Jun. 2018 (to be submitted).
- R. Hanna, V. Disfani, J. Kleissl, D.G. Victor, “A new simulation model to develop and assess business cases for commercial microgrids,” North American Power Symposium (NAPS) 2017, Sep. 2017.
- Hanna, R., Ghonima, M., Kleissl, J., Tynan, G., Victor, D.G., 2017. Evaluating business models for microgrids: Interactions of technology and policy. Energy Policy 103, 47-61. doi: 10.1016/j.enpol.2017.01.010.
- R. Hanna, V. Disfani, J. Kleissl, “A game-theoretical approach to variable renewable generator bidding in wholesale electricity markets,” North American Power Symposium (NAPS) 2016, Sep. 2016. doi: 10.1109/NAPS.2016.7747919.
- I.S. Bayram, V. Zamani, R. Hanna, J. Kleissl, On the Evaluation of Plug-in Electric Vehicle Data of a Campus Charging Network, 2016 IEEE International Energy Conference, EnergyCon 2016, Leuven, Belgium. doi: 10.1109/ENERGYCON.2016.7514026.
- Hanna, R., Kleissl, J., Nottrott, A., Ferry, M., 2014. Energy dispatch schedule optimization for demand charge reduction using a photovoltaic-battery storage system with solar forecasting. Solar Energy 103, 269-287. doi: 10.1016/j.solener.2014.02.020.
- R. Hanna, D. Gonatas, K. Murray, J. Kleissl. Development and simulation of battery energy storage and inverter control for PV ramp rate smoothing, Apr 2016. (Report submitted for CSI RD&D5 Subtask 3).
- D.A. Nguyen, P. Ubiratan, M. Velay, R. Hanna, J. Kleissl, J. Schoene, V. Zheglov, B. Kurtz, B. Torre, V. Disfani. Impact Research of High Photovoltaics Penetration Using High Resolution Resource Assessment with Sky Imager and Power System Simulation, 2015. Available online.
- W. Torre, R. Hanna, J. Kleissl. Cumulative Impacts of High Penetration of Electric Vehicle Charging and Photovoltaic Generation on Distribution Circuits, 2015. Available online.
Selected Conference Presentations and Invited Talks
- Poster: R. Hanna, D. Victor, V. Disfani, J. Kleissl. The value of reliability for microgrids. DistribuTECH 2017, San Diego, CA, 2017.
- Paper: R. Hanna, V. Disfani, J. Kleissl. A game-theoretical approach to variable renewable generator bidding in wholesale electricity markets. NAPS 2016, Denver, CO, 2016.
- Keynote Talk: R. Hanna, D. Victor. Squaring Microgrid Business Models with Grid Decarbonization. CaFFEET 2015, San Francisco, CA, 2015.
- Poster: R. Hanna, J. Kleissl, A. Nottrott, M. Ferry. Energy dispatch schedule optimization for demand charge reduction using a photovoltaic-battery storage system with solar forecasting. EESAT 2013, San Diego, CA, 2013.
Other Appointments and Affiliations
- International Institute for Applied Systems Analysis (IIASA), Young Scientists Summer Program, Laxenburg, Austria, Jun-Aug 2017.
- Deep Decarbonization Initiative, UC San Diego, 2016-present.
- Center for Energy Research, UC San Diego, 2014-present.
- Teaching Assistant: MAE 126a – Environmental Engineering Lab. Winter 2016. Course taught by Prof. Jan Kleissl.
- Teaching Assistant: MAE 110a – Thermodynamics. Winter 2014. Course taught by Prof. Jan Kleissl.
- Teaching Assistant: MAE 121 – Air Pollution Transport and Dispersion Modeling. Spring 2013. Course taught by Mark Bennett.
Ph.D. Mechanical Engineering. University of California, San Diego. Dissertation: The value of reliability for microgrids: Modeling interactions of technology choice, reliability and economics (ongoing).
M.S. Mechanical Engineering. University of California, San Diego, 2013. GPA: 3.69.
B.S. Mechanical Engineering. Washington University in St. Louis, St. Louis, Missouri. 2011. GPA: 3.97.
B.A. Physics, Mathematics minor. Pacific Lutheran University, Tacoma, Washington, 2009. GPA: 3.73.