The Path To Supply Clean Energy to Every Home

NREL Analyst Sherin Ann Abraham Sheds Light on the Challenges of Modernizing the Distribution Grid

July 30, 2024 | By Sherin Ann Abraham | Contact media relations

Sherin Ann Abraham is a part of the Grid Planning and Analysis Center at the National Renewable Energy Laboratory (NREL). In this installment of NREL's "Tell Me Something Grid" series, she discusses the importance of modernizing the distribution grid as renewable energy gets deployed.

Across the globe people are talking about decarbonizing our future energy systems. But how do we actually get there?

Much of the answer lies in the distribution grid—the complex network we use to deliver electricity from power plants to homes, businesses, and other end users. Revamping our current distribution grid will be essential for enabling the widespread adoption of electric vehicles, heat pumps, electric cooking, and more, ultimately driving large-scale electrification and decarbonization.

My background is in electrical engineering, so power systems have always excited me. And for the past five years, I've worked alongside my colleagues at NREL to understand how our current distribution power systems will need to change to keep up with and support the clean energy transition.

Modeling our future distribution grid is complex, presenting more challenges than ever in achieving an affordable, reliable, and secure power system. But the reason we have these challenges is exciting—it's because we are now paying unprecedented attention to certain aspects of the grid. The energy transformation offers major opportunities with more solutions on the horizon to modernize and decarbonize our power system, including a surge in distributed solutions.

For instance, we're focusing on a more interdisciplinary approach to our research, hence ensuring all communities can have equitable access to electricity as diverse resources are added to the distribution grid. This means planning such that all customers have a reduced risk of power outages and can install electrified appliances, electric vehicles, solar, storage, and other technologies without grid or service transformer limitations. There's a lot of work we need to do to ensure no people are left behind in the energy transition.

One Part of the Grid Can Affect Everything

One project we're currently working on with the U.S. Department of Energy's Office of Electricity focuses on a specific part of the distribution grid: transformers. If you imagine the distribution grid as a system of water pipes, transformers are like adjustable valves, ensuring the right pressure of water is delivered to your sink. Transformers adapt the voltage of electricity, just like valves regulate water, so that it reaches homes smoothly and in the right form to be used.

Right now, the United States is experiencing an unprecedented imbalance between supply and demand for distribution transformers. On one hand, there's a shortage due to difficulty in workforce retention for manufacturers, shortfall in skilled labor and raw materials, and supply chain challenges. On the other hand, there is a rise in transformer demand due to aging infrastructure, increasing electrification, and growth in renewable energy. Today, if a transformer needs to be installed or replaced, many utilities are out of luck. The wait time to get a transformer can be over two years, and it can cost up to eight times more than it used to before 2022.

Although the shortage of distribution transformers is just one aspect of the entire distribution system, it impacts everything. The shortage can cause delays in the deployment of renewable energy, development of new housing communities, and electrification, as well as grid modernization and grid restoration under extreme weather impacts. Different utilities, and therefore different communities, are impacted differently by this shortage because larger utilities may have the capital to place an order for a large number of transformers that will fulfill their future needs, while smaller ones do not.

A significant part of my work is creating solutions to address this and avoid similar supply chain challenges in the future by working to produce an estimate of current and future demand for distribution transformers for the whole country, which currently does not exist. Quantifying the demand can help power sector stakeholders, manufacturers, and federal partners identify and implement practical actions that will help to ease the supply-demand mismatch for distribution transformers. But to quantify the transformer demand, we must understand the drivers for this demand.

Based on preliminary results, load demand growth across the various sectors (residential, commercial, transportation, and industrial) are expected to increase 160%–260% compared to 2021. Factors like electric vehicles, heat pumps, electric cooking, and data centers vary immensely by state, which is why demand modeling is a critical piece in distribution system planning. In March 2024, we released a report outlining the major drivers of long-term transformer demand, which included some preliminary findings. In continuation, our team has been refining the methodology for this nationwide distribution transformer study, to help ensure that all the utilities are able to get the necessary infrastructure in place to improve future energy access in their communities.

The (Fun) Challenge of Grid Planning for an Entire Country

In the Grid Planning and Analysis Center at NREL, we also have several projects that allow us to look at not just one part of the power system but at the power system as a whole. For the Lithuania 100% Renewable Energy Study, we're evaluating future distribution grid scenarios for all of Lithuania. We're not just looking at transformers but all the assets involved in the electric distribution grid to understand how much infrastructure they will need to adapt to reach future renewable energy goals set by the government of Lithuania. Our work involves analyzing everything from substations, feeder lines, transformers, low-voltage lines, and the end-service drops. And it's far from easy

One of the primary challenges in my work is achieving a balance between detailed modeling and necessary assumptions to ensure a comprehensive study's completion. This is especially crucial when considering integrated aspects such as solar generation, load dynamics, electrification trends, weather-driven demand variations, and infrastructure modernization. At its core, this work involves combining diverse disciplines and expertise to model and plan effectively for the future grid. The crosscutting element makes the work collaborative by nature, which I find particularly interesting and rewarding.

Empowering Energy Consumers Worldwide

The electric grid has already changed in many positive ways. Today, many customers want to be more engaged in their energy journey. It's an exciting space because it's empowering customers to be more conscious and intentional about how they're consuming energy. One primary goal of a modernized distribution grid is for everyone to have the ability to power their day-to-day lives with decarbonized transportation, heating and cooling, and cooking. But if we do not have the infrastructure in place, many people do not have the option to do that.

When I work on these projects, I'm especially inspired by the international partnerships and collaborations we have because that's how we're going to ensure this energy transition happens all around the globe. I remind myself that at any given point during this period of transition, we might not be at the level of clean energy that we want to be, but we are on an exciting path toward making clean energy accessible to all.