SmartGrid

Battery-management systems (BMS) comprise electronics and software designed to monitor the status of a battery pack, estimate its present operating state, and advise the battery load regarding the maximum amount of power that may be sourced or sunk by the load at every point in time while maintaining safety and acceptable battery-pack service life. This lecture will first discuss BMS sensing requirements imposed by these tasks. It will then give an introduction to state-of-art equivalent-circuit-model-based algorithms to estimate the battery pack's operating state: nonlinear Kalman filters for state-of-charge, recursive total-least-squares methods for state-of-health, direct computations for state-of-energy, and a bisection method for state-of-power.

Lithium-ion battery packs for transportation and grid services represent a large investment that must be continuously monitored to ensure safety, to maximize performance, and to extend life to the greatest degree possible. The best available battery-management methods are model based; that is, they depend on sets of equations ("models") that describe the behaviors of the lithium-ion cells in the battery pack in order to perform their management tasks. This lecture will first derive "equivalent-circuit" models, which are presently state-of-art. It will next introduce "physics-based" models, which have potential benefits for future battery-management systems. Physics-based models are computationally complex, so a method will be presented to develop highly accurate reduced-order models suitable for battery management. Finally, a high-level overview of mechanisms of cell degradation will be given to motivate power-limits computations to be discussed in the next lecture.

We will discuss the characteristics that define a battery, such as energy density, safety, and efficiency. Materials properties determine the operating envelope of the batteries, such as temperature. Popular positive electrode chemistry for lithium-ion batteries will be reviewed.

We will introduce the four main components of a battery: positive electrode, negative electrode, electrolyte, and current collector. A battery is classified by the phase of the electrode, electrolyte, energy carrier and type of chemical reaction. We will briefly introduce lithium-ion, solid-state, liquid metal, sodium sulfur and lithium air battery chemistries. Finally, we will discuss charging and discharging characteristics.

Buildings account for the largest share of U.S. greenhouse gas emissions at 32% of the total, followed by industry at 30%, transportation at 29%, and agriculture at 9%. Clearly, any program to greatly reduce greenhouse gas emissions must include buildings. This talk will explore the opportunities and challenges to greatly reducing greenhouse gas emissions in the building sector, using as a case study a recent solar retrofit of an existing house that rendered it "zero-carbon." Implications for the future of the utility system will be discussed.

Thin-film solar cells, which use light-weight, highly-absorbing semiconductors, have the potential to dramatically lower manufacturing costs and accelerate deployment of solar energy via mechanically flexible architectures. Hybrid metal halide perovskites are the leading materials for this next-generation solar technology by virtue of their unprecedented optoelectronic properties and their synthesis from earth-abundant elements. The groundbreaking promise of perovskites is that they can be manufactured by scalable solution-coating methods, making them a potentially low-cost and high-performance energy technology with projected levelized cost of electricity (LCOE) below 3¢ / kWh.

This talk will discuss the current understanding of the optoelectronic properties of perovskites as well as how these properties inform the design of single-junction and tandem perovskite-silicon cell architectures. We will consider routes to upscaling perovskite module fabrication and look at challenges related to the fundamental thermomechanical reliability of these material systems.

Competing standards often proliferate in early stages of product markets and may lead to socially inefficient investment. This paper studies the effect of unifying three incompatible standards for charging electric vehicles in the U.S. from 2011 to 2015. I develop and estimate a structural model of vehicle demand and charging network investment to quantify the impact of a uniform charging standard. Variation in federal and state subsidies identify the demand elasticities. Counterfactual simulations show moving to a uniform charging standard increases consumer surplus by $500 million; car manufacturers build 2.8% fewer charging locations and sell 20.8% more electric vehicles.

Power systems are facing grand challenges from increasing dynamics and stochastics from both the generation and the demand sides. This has caused great difficulty in designing and implementing optimal control for the grid in real time. Tremendous efforts have been spent in the past on computational methods and advanced modeling techniques that provide faster and better situational awareness, based on measurements from advanced grid sensors, PMU as an example. However, as grid operators are heavily involved in the decision-making process, the entire procedure has not been made fully automated, limiting the potential of such applications. That is, not only does the 'grid' need to perceive faster, it also needs to think and act faster. Towards this end, sub-second autonomous control schemes need to be developed. Over the past years, the PMU & System Analytics Group at GEIRI North America has built up an autonomous grid dispatch and control platform using deep reinforcement learning, the Grid Mind. Combined with Grid Eye, the grid monitoring and situational awareness platform, Grid Mind has demonstrated promise in helping address the pressing issues modern power systems faces. This talk will summarize this developmental effort while focusing on the key technologies utilized for the Grid Mind framework.

Recently, the academic and industrial literature has arrived at a consensus in which the electric power grid evolves to a more intelligent, responsive, and dynamic system that propels the sustainable energy transition. This evolution is caused by several drivers including decarbonization, growing electricity demand, deregulation of electricity markets, active end-user participation, and digital innovations in energy technologies. On the supply side, the introduction of variable energy resources (VERs), like solar and wind, necessitates fundamental changes in the power grid's dynamic operation. VER forecasts are uncertain and their profiles are intermittent thus requiring greater quantities of operating reserves. In such a case, fast-ramping natural gas and hydro-electric power plants take on a prominent grid balancing role. At higher levels of solar PV and wind generation, dispatchable demand-side resources become the only remaining option for grid balancing. These devices are not just energy artifacts, but also exist within other engineering systems. Consequently, their integration gives rise to new multi-disciplinary challenges such as electrified transportation and the energy-water nexus. This presentation seeks to shed light on the increasingly intertwined futures of energy, water, and transportation resources. It draws upon three full-scale case studies: The ISO New England System Operational Analysis and Renewable Energy Integration Study, New England Energy-Water Nexus Study, and Abu Dhabi Electric Vehicle Integration Study. Together, these studies show that while all three types of resources have the potential to disrupt the other, they can also be harmonized to create sustainable synergies across all three engineering systems

Individuals of all genders invited to be a part of:
#StanfordToo: A Conversation about Sexual Harassment in Our Academic Spaces, where we will feature real stories of harassment at Stanford academic STEM in a conversation with Provost Drell, Dean Minor (SoM), and Dean Graham (SE3). We will have plenty of time for audience discussion on how we can take concrete action to dismantle this culture and actively work towards a more inclusive Stanford for everyone. While our emphasis is on STEM fields, we welcome and encourage participation from students, postdocs, staff, and faculty of all academic disciplines and backgrounds.