Caltech Leads the Way to a Green Power Grid – Pasadena Now
California’s energy grid, an engineering marvel 150 years ago, needs a makeover. Today, thanks to an interdisciplinary group of researchers, Caltech is working to transform energy systems by developing a “smart grid”: a flexible, responsive and efficient system that integrates renewable energy sources while meeting the growing demand for energy.
Californians are increasingly experiencing the effects of climate change, from drought and water shortages to extreme heat. These challenges underscore the urgent need to switch from greenhouse gas-emitting fossil fuels to renewable energy sources such as wind and solar. In 2018, California committed to supplying electric customers with 100% renewable and carbon-free energy sources by 2045.
A crucial step in this transition is to restructure the electrical grid, the complex web of hardware and software that brings electricity to our doorsteps. With the support of public and private partners, engineers, economists, mathematicians and computer scientists at Caltech imagine and test the foundations of tomorrow’s network. Their advancements include everything from creating intuitive algorithms and hardware that ensure electric vehicle (EV) charging stations consume energy when it’s cheap and plentiful, to implementing new cost-saving structures. that prevent market players from manipulating energy prices.
“Much of the infrastructure has already reached a stage where it can be integrated and implemented,” says Adam Wierman, professor of computer science and mathematical sciences. “There are smart devices for sensing and communication, and solar and wind are cost competitive. This means that there will be short-term progress. The question is when will we hit that wall where the current architecture ceases to be sufficient, where power outages begin to become more likely, where costs begin to rise. Our research aims to break through that wall, so that when you get there, you can always progress.
Yesterday’s power grid
Conventional grids have relied on coal or nuclear power plants located near areas of high electricity demand. Renewable energy generation systems, such as solar panels and wind turbines, are often located in open spaces away from urban areas, creating the need for more storage (e.g. pumped hydroelectric energy storage or batteries) and greater transmission capacity (e.g. power lines).
The grid was also designed to distribute a stable and predictable flow of electricity created by burning fossil fuels on demand. Renewables from wind and solar sources fluctuate with weather conditions and are difficult to predict. Without significant, long-term energy storage, this can lead to an imbalance between the amount of electricity generated and the amount needed at any given time.
Added to these challenges is the expectation of an increase in demand for electricity as more people drive electric vehicles and install electric appliances in an effort to decarbonize. The network of the future must be able to develop to meet this increased demand.
Caltech Smart Grid Solutions
When energy supply is less predictable, energy demand must be more flexible to avoid overloading the grid. Smart planning – drawing electricity from the grid when renewable energy is available – could make the grid more compatible with the variability of wind and solar power.
Caltech researchers have developed mathematical tools that determine when to use and when to conserve energy based on the energy available on the grid. These tools solve the problem of stabilizing grid voltages even when power from renewable sources fluctuates. This new approach can be applied to distribution networks that take electricity from large substations and deliver it to homes, buildings, streetlights and other energy consumers in an area.
With a smart scheduling rack, you can tell your dishwasher if you need the dishes right away or if the job can wait a few hours until the rack is less busy. The huge data centers run by Google, Amazon and other companies could only launch power-intensive activities, such as data archiving, when solar and wind power become available.
Caltech has already launched a solution for a major energy consumer: electric vehicles. Steven Low, Frank J. Gilloo Professor of Computer Science and Mathematical Sciences and Electrical Engineering, George Lee, former Caltech graduate student, and Zachary Lee, former Resnick Sustainability Institute graduate researcher, invented the adaptive charging network, a smartphone compatible platform that car parks can use. to maximize the efficiency of EV charging stations. For example, a person may leave their electric vehicle parked for a full working day but need relatively little power to recharge the battery. This person could wait until later in the day, when energy is more available and cheaper, to recharge. Another person, who needs to recharge before going to a lunchtime meeting, could start receiving electricity immediately. This technology, licensed by a company called PowerFlex, is now operational in Caltech’s parking structures and is being rolled out across the country.
But smart planning alone is not enough. A network running on renewable energy also requires a major overhaul of the way the network is managed and regulated.
Today’s electricity grid is based on a centralized approach, which means that all data is collected and control decisions are made at a central management center to ensure that enough electricity is routed to where it is needed. The smart grid, on the other hand, uses a decentralized approach, in which everything from dishwashers to data centers can interact with and glean information from the grid to optimize energy consumption without human intervention. This requires new algorithms designed with cybersecurity threats in mind from the start.
The current system also uses markets that predict customer electricity demand a day in advance, allowing power plants to generate and sell enough electricity to meet that demand. This market structure does not work when fluctuating renewables come into play. Caltech researchers, like Wierman, are doing theoretical work on the smart grid and the network of markets it will produce. A potential problem is that renewable energy-based markets open the door for companies to manipulate prices by shutting down generators. While the working status of a normal generator can be monitored, solar and wind power make it nearly impossible to verify how much electricity should have been generated as it is difficult to know if there was wind. or sunshine at a certain time. Wierman creates market designs that would reduce this risk.
Caltech’s hometown of Pasadena is a hands-on lab for Smart Grid Institute researchers: the city has promoted the use of solar panels and electric vehicles, providing a real-time, real-time example of the challenges to the integration of renewable energies into a conventional network. . Caltech is working with Pasadena Water and Power on a project to install and strategically program batteries that could store solar and wind power for use when power supplies are low.
“Grand engineering challenges inspire much of the research at Caltech, especially in the broad area of sustainability,” says Harry Atwater, Otis Booth Leadership Chair of the Division of Engineering and Applied Science, Howard Hughes Professor of Applied Physics and Materials Science, and director of the Liquid Sunlight Alliance. “Inventing and developing technologies to accelerate the transition to sustainable energy infrastructure is a large part of our research portfolio – our faculty, students and alumni are at the forefront of solving large-scale problems that will have a long-term impact.”