The US electricity transmission system is unprepared for the growth in new electricity that’s necessary to meet US climate goals. Four solutions could help prepare the grid for higher demand and complement the expansion of the transmission system.
The clean energy transition requires massive investments in many areas of the electricity sector. New generation facilities need to be built to provide clean power, new distribution lines need to accommodate increasing demand from the electrification of the economy, and new transmission lines need to be built for delivering power from where that power is generated to where the power is needed. So much new electricity infrastructure is needed that concerns are growing that we won’t be able to build everything fast enough. While the recent $1.3-billion infusion from the US Department of Energy into three interstate transmission projects demonstrates current efforts to support the grid, the projects represent only a small fraction of national-level needs.
In particular, two primary concerns exist regarding infrastructure for electricity transmission: (a) complex webs of federal, state, and local regulation make transmission too difficult to build, and (b) generation supply and electricity demand are changing so much that knowing where transmission will be needed most in the decades to come is difficult. In a recent report, my coauthors and I explore how investments in the electric grid that don’t require new transmission lines could play a role in advancing the clean energy economy. We discuss these different investments and in what circumstances these investments can help relieve or postpone the need for new transmission lines. Through a better understanding of how these technologies and activities can contribute, policymakers and grid planners can more accurately assess where new transmission lines are most urgent and where other solutions may be available.
In our report, we explore four main categories of investment: grid-enhancing technologies, distributed energy resources, demand management, and microgrids. Each of these investments can deliver unique benefits in terms of relieving congestion in the transmission system, serving demand for electricity, and increasing the reliability of electricity infrastructure.
Grid-enhancing technologies maximize the efficiency of transmission lines and minimize congestion in these lines with relatively low-cost upgrades to hardware and software. These technologies use sensing technologies and smart algorithms to enable more power to flow on transmission lines and can be a powerful investment in high-density areas with many existing transmission lines. Grid-enhancing technologies also can enable the lines to withstand electricity from energy resources that generate varying amounts of power, such as wind and solar.
Distributed Energy Resources
Distributed energy resources can be critical to integrating renewable energy into the grid. Different technologies have different benefits, but each technology contributes to more affordable electricity and reduces the burden on the transmission system by offering an opportunity to colocate energy demand with supply from smaller generation systems. These smaller systems can preclude or reduce the need to connect large, utility-scale generation projects to centers of demand (and avoid permitting and siting challenges for transmission lines).
Demand management has long been considered a critical element in improving the affordability of electricity in the context of a decarbonized grid. Demand management can reduce the need for new infrastructure by reducing the peak demand for electricity, which at higher volumes would require connecting more sources of generation to the bulk power system. Demand management can move some types of electricity consumption to time periods when the supply of renewable electricity is abundant. This shift in consumption can maximize the utilization of renewables and minimize the need for fossil fuel resources.
Microgrids, which are composed of various distributed energy resources, largely benefit electricity users who do not want to or cannot rely on the bulk power system by creating a system for the supply and distribution of electricity that can operate independently from the larger grid. The benefits of microgrids are especially relevant in remote areas, on islands, and in disadvantaged communities where transmission infrastructure is weak and more vulnerable, and where additional investment in transmission may offer inadequate solutions and be less effective or more costly than creating microgrids with self-serving generation that can operate independently.
Regulatory, cost, and market barriers may slow the growth of these technologies and activities, despite the benefits that investments in each of these four solutions can provide. Our report goes into detail about the challenges that each of these investments would encounter in implementation, along with recommendations for new research that could clarify how investments could help build a clean energy future.