The U.S. electrical grid faces many challenges over the coming decades. Aging infrastructure needs to be replaced, demand for power continues to increase, and climate change is driving a push for clean and sustainable energy. These combined challenges strain existing transmission systems to provide reliable power. Upgrades to the transmission system can be costly and time-consuming, which has created a backlog of transmission projects across the nation. Grid-enhancing technologies (GETs) provide operational support while larger upgrades are completed enroute to a transmission system that reliably integrates new power sources.
To fill the knowledge gaps of GETs, the Department of Energy Office of Electricity and Wind Energy Technologies Office established the Transmission Optimization with Grid-Enhancing Technologies (TOGETs) project. This project guides research to fill knowledge gaps of GETs, develops new modeling and simulation methodologies, and conducts a full-scale, multifaceted field exercise on INL’s Power Grid Testbed. INL’s nearly two-decades of R&D expertise in Dynamic Line Rating adds significant depth to the expansion of innovative solutions.
A better understanding of how various GETs can work together will allow regulatory bodies and utility providers to evaluate the benefits and risks of these devices and techniques. The combination of GETs leads to improving the use of existing transmission lines, supporting transmission upgrades as they occur, maximizing power transfer, and reducing lost revenue due to congestion and inefficiency.
Department of Energy Funding Opportunity for GETs
February 2023: The U.S. Department of Energy’s Office of Electricity and the Office of Energy Efficiency and Renewable Energy’s Wind Energy Technologies and Solar Energy Technologies Offices issued a $6.5 million funding opportunity announcement to conduct research, development and demonstrations for innovative approaches that demonstrate real-world benefits and use of GETs. Application deadline is May 9.
GETs Technologies Studied
The two technologies studied for this project are not the only types of GETs, but they represent mature technologies ready for industry deployment today.
Dynamic Line Rating
Hardware and software used to access weather conditions such as wind speed, direction and ambient air temperature to determine the true temperature of a conductor and consequently the maximum power that can safely flow on a transmission line at a given time.
Power Flow Controller
A hardware or software device that can actively push and pull power by changing the reactance in the lines. This is useful for redistributing power flow in a mesh network to relieve congestion.
TOGETS Project Overview
The 2022 U.S. Department of Energy (DOE) Report “Grid-Enhancing Technologies: A Case Study on Ratepayer Impact,” focused on the impacts of integrating GETs onto existing transmission lines. GETs can defer or reduce the need for significant investment in new infrastructure projects and increase the use of renewables by maximizing the capacity of the current infrastructure. The report outlined key findings from a case study that evaluates a near-future scenario (2025) in the New York Independent System Operator service area to understand how GETs could impact the region.
- To integrate the large amounts of wind and solar resources needed to achieve the state’s goal of 70% renewable energy by 2030, significant transmission investment is required. However, GETs and other enabling technology can help facilitate this transition by making better use of existing transmission lines and potentially deferring or augmenting costly traditional transmission upgrades.
As part of the TOGETs Project, INL followed the recommendations of the DOE 2022 Report to Congress by assembling a task force to enable the transparency of GETs. Electric utilities are traditionally risk averse organizations, for good reason. However, the gaps in public knowledge with respect to GETs leads utilities to prioritize established, known solutions. The INL-convened TOGETs task force is charged with helping provide industry with the data needed to fairly consider GETs and ameliorate perceived risk of the modern technologies.
Phase one: Compile information on cost, data, and outcomes from previous studies. This information is vital to understand the use of GETs devices and allow all entities to leverage lessons learned from earlier efforts to streamline future investments. Studying existing data will allow the task force to collect these lessons learned into a centralized repository and identify gaps in the publicly available literature. This work will allow the TOGETs team to focus on filling these gaps.
Phase two: The demonstration will use dynamic line rating and power flow control technology to clarify and answer unaddressed concerns such as integration challenges, cybersecurity and data management. The task force will make collected data publicly available. This will make GETs implementation and operation more transparent to future users.
GETs Costs
Since the GETs industry is relatively new, potential device users do not always have a good idea of how much an investment in GETs will cost. Similarly, there has not yet been a valuation framework established to estimate the benefit provided by GETs. One challenge with valuation is that many benefits may come from avoiding additional costs, such as using higher priced generators or even avoiding an outage caused by congestion. INL has identified multiple factors to consider in a cost/benefit analysis:
- Cost of devices
- Cost of design work (impact analysis, device placement, sizing needs, siting analysis)
- Cost of installation (extra materials, labor, etc.)
- Cost of maintenance (monitoring device health)
- Cost of licensing (continuing to receive support and/or connection to devices from vendors)
- Avoided costs of energy (e.g., using more wind energy instead of a peaker plant generator)
- Avoided costs of outages (e.g., can safely push more power over a line or can redirect power to reduce congestion)
- Ability to serve more load
- Ability to perform maintenance in opportune windows
Modeling and Simulation
No potential GETs user will consider deploying these technologies without first understanding how they will impact their system. INL is working with project partners to build generic models of GETs technologies that can be used for power system modeling and simulation. Many GETs devices have the potential to change some of the fundamental building blocks of power system modeling. For example, line impedances are assumed to be static, but with PFC, they could be a controllable value. Line limits are also assumed to be static, but dynamic line rating uses factors outside of traditional power system modeling to make this a dynamic value. While this adds complexity to an already dynamic and complicated problem, the solution unlocks potential for the grid of the future.
Power flow modeling of the system can determine congestion and curtailment under both standard N-0 configurations for economic dispatch, as well as the congestion and curtailment under the N-1 contingencies (when one line is temporarily out of commission), which create tighter restrictions on the system. Under regular operations, there is typically high headroom on the line between its load and thermal capabilities, with large constraints only apparent in periods of high system electrical use or during N-1 contingency security. By building PFC and DLR into power system modeling, the impact of these GETs on peak times or contingency situations can be isolated, rather than generic statements claiming increases in capacity.
Deployment Challenges
Through executing a demonstration at the INL Site, the research team has learned and documented challenges with the deployment process. By documenting the process and solutions found, the team hopes to provide resources that promote the adoption of GETs and may avoid discouraging potential GETs users from adopting the technology.
- INL worked with vendors to use its on-site cellular network, promoting security of wireless communications.
- INL helped vendors navigate the registration process to be a subcontractor for government funds, which may help if any future projects are partially funded by government awards.
- INL worked with vendors to customize solutions to the field constraints at the Site. Being able to adapt deployment or installation practices to the customer’s needs will be important for GETs as they can be deployed for a wide range of potential applications.
Resources from the demonstration project, such as the request for proposal, test plans and lessons learned, will be published for industry reference.
Energy Curtailment Avoided vs. Costs
A recently published report, Grid Enhancing Technologies: A Case Study on Ratepayer Impact, focused on a set of lines in western New York that was analyzed for improving integration of new wind and solar power through implementing DLR and PFC technologies. The GETs cases provide options to address curtailment at a fraction of the cost. The payback period appears to be faster for GETs than traditional upgrades, even though the life cycle is shorter. The study determined a range of costs for estimated GETs versus the curtailment avoided.
Industry Engagement
INL is working with several industry partners to research and advance the knowledge of Grid Enhancing Technologies and integrate solutions.
Project Partners
- EnerNex
- Power Engineers
- Telos Energy
Project Technology Providers
- WindSim Power
- Ampacimon
- Smart Wires
