This article looks at the challenges faced by utilities in wanting to expand their renewable energy portfolios as a result of how energy infrastructure were initially designed as well as provide some insights into how energy providers can address such challenges.
Whether it is an initiative to reduce emissions or a plan to go 100% renewable, it seems like every other week a new city or company announces a renewable energy goal. In the US, states such as California and Hawaii now have mandates to procure 100% renewable or zero-emission electricity. Similarly, more than 150 large companies have pledged to source 100% renewable electricity as members of the RE100 global initiative.
However, what’s missing from these goals is a detailed plan to upgrade the grid to be able to handle increasingly large amounts of intermittent renewable and distributed energy resources.
To reach a 100% renewable goal, many organisations purchase enough renewable energy to match the amount of electricity they use annually. Google explains their approach to renewable energy contracts in an April 2018 blog post, noting that their 3GW of wind and solar power make them the largest corporate purchaser of renewable energy in the world. Other big companies, such as Microsoft, Walmart, and Apple also buy large amounts of wind and solar power.
All that wind and solar power adds up, and its intermittency isn’t something our 100-year-old electric grid can handle with ease.
When most of the power grids were built, decades ago, they were designed to deliver electricity one way, from large central power plants to population centers. There was no plan to include small generators on the grid, like rooftop solar or fuel cells, because they weren’t yet invented or mainstream.
Energy storage can help, but it won’t solve the problem alone. What is needed is a smarter, faster operating system for the grid, designed specifically to manage renewable and distributed energy resources.
A Grid in need of an upgrade
Conventional grid control technology was designed to handle steady or high-inertia generation from fossil fuel power plants. Renewable power facilities do not have spinning mass and produce low-inertia generation, which requires faster control to dynamically manage the flow of electrons onto the grid.
In addition to changing needs in power management, many grid functions that could be automated by a computer are still completed by hand using limited forecasting and estimating tools. Humans continue to monitor and make guesses as to how to deploy power resources and solve demand issues. Some systems still run on a DOS (disc operating system)-like programme, which had its heyday between 1981 and 1995.
Finally, on top of 1990s-era technology that is still being used throughout the grid, many grid control systems are running SCADA functions that provide a snapshot of the system to the human operator every few seconds. These systems that rely on human operators are becoming less effective as the grid and its components become more dynamic and require greater speed and data processing than traditional systems can handle. Fortunately, new technology is available that can do everything the old SCADA systems can do and much more.
A Modern Grid Makeover
To successfully integrate more renewable and distributed generation, the grid must become smarter, more autonomous, and faster. This new grid is networked to allow for two-way flow of electricity and real-time communication and uses machine learning to provide self-adjustment, contingency planning, and remote operation.
Modernising our electric grids means leveraging existing technology on the system and marrying it with new as SCADA, advanced meter data management and applications such as smart home or HVAC control systems to access and optimise energy generation, distribution and storage and consumption in near real time.
In the third quarter of 2017, Horizon Power, a state owned utility in Western Australia embarked on an initiative to improve management of its existing as well as add more distributed energy resources onto its grid network for reliability.
The energy provider to 48,000 metering points commissioned PXiSE Energy Solutions’ Active Control Technology as the distributed energy resources (DERs) management system.
The technology will run on a standard Microsoft Windows platform, use embedded OSIsoft software and synchro-phasor data to enhance, analyse and respond to grid data from DERs.
High-speed control technology can ‘upgrade’ the grid by supporting the increased use of renewable power, without sacrificing reliability or power quality.
To move away from the century-old method of using slow, centralised generators to balance the grid, we must adopt new grid control paradigms that take advantage of the speed, precision, and multi-tasking that inverter-powered resources can provide. These resources can then compliment the slow but powerful spinning generation resources to maximise the value of each unique energy resource. If we do not shift this grid operations mindset and fail to upgrade our systems and thinking, we risk ignoring a foundational weakness in our utility grid and holding ourselves back from realising the true promise of renewable energy.
Terry Mohn, general manager of Advanced Microgrid Developments for Horizon Power, added: “With increasing customer demand for behind the meter energy resources, we will need innovative technology to enable us to efficiently manage the resources while maintaining our highest safety and reliability standards.”
About the author:
Patrick Lee founded and leads PXiSE Energy Solutions, LLC., a subsidiary of Sempra Energy with an investment by Mitsui & Co., Ltd. Lee is also vice president of infrastructure and technology at Sempra Infrastructure, LLC.
Lee is a proven executive with a successful track record. He completed a $1.8B, infrastructure project with 19 awards and has led numerous business operations with significant financial outcomes. He has over 30 years of energy industry experience in electric system planning, design, construction, operations, energy markets, renewables, and technology RD&D.