Assessing the Impacts of Electric Vehicles (EV) Charging on Electricity Grids


This is part of a series that explores the Five Key Challenges to Widespread Adoption of Electric Vehicles (EVs). In this article, we drilldown to take a closer look at the issue of how the growth in EV charging is impacting electricity grids.

A Wide Range of Projections: “Doom vs. Boom”

There is no doubt that the rapidly growing adoption of EVs along with the need to charge them will have impacts on the electrical grid. However, there has been a fairly diverse range of opinion about how those impacts will play out.

Figure 1 – The impact of EVs on grid reliability

On one side, there has been a lot of anti-EV hype about how existing grids cannot support a full transition to EV charging and the stresses on the grid will be immense. These scenarios most often include unrealistic assumptions such as predicting what could happen if all existing ICE vehicles were turned into EVs overnight.

According to some experts, “If all US cars were EVs, they would need a total of 1,106.6TWh, which is 27.6% of what the American grid produced in 2020.” But others respond that the chances of all EVs being charged at the same time are statistically low.

On the other hand, common sense scenarios by many experts instead point to likelihood of a more gradual transition to EVs over a number of years. For example, some even point to how previous widespread transitions were carried out smoothly, such as how the electrical grid adapted to the rise of air-conditioning usage over a couple of decades.

Figure 2 – EVs recharging at a public parking lot

Still other pundits have put forth rosier predictions that having millions of fully charged EVs always connected to the grid at any point in time can actually improve the ability to meet peak demands by drawing electricity stored in those EVs back into the grid when needed.

The following sections provide a deeper look at some of the key issues and actions underway to improve grid capacity and resilience.

Expanding Grid Infrastructure and the Use of Renewables

When considering the impact of EVs, it is important to take a broad and long view for context on changes that are already underway in the grid. The key factors include expanded investment in capacity, transmission networks and renewable energy sources.

Figure 3 – Power generation and transmission capacity are expanding as EV adoption grows

According to, “EVs currently have a negligible impact on the grid. Based on the average amount of electricity that EVs use, the full fleet of roughly 2.5 million EVs in the U.S. uses less than half a percent of the total energy the U.S. produced in 2021.” Furthermore, “Electrifying the world’s vehicle fleet would add just 25% to global electricity demand in 2050, while global electricity supply is forecast to grow more than 60% from 2020 levels by 2026.”

In the United States, the current administration’s National Electric Vehicle Infrastructure (NEVI) Formula Program, promises $5 billion in funding years to implement over 500,000 EV stations on highways over the next five years.

Two other important trends that will mitigate stresses from EV charging are 1) the increasing use of renewable energy sources and 2) the expansion of electricity storage options within the grid.

Traditional power grids for over a century were designed around a model that simply increased the output of fossil fuel power plants to handle usage peaks without the need for in-grid storage. However, the shift to renewables has brought the need for grid storage and overall efficiency to the forefront.

Most renewable sources are dependent on external factors, for example solar produces power when the sun shines and wind turbines produce power when the wind blows. Therefore, any excess power from renewables that is not used immediately can go to waste. In this new environment, electricity storage in the grid has become a critical factor for success.

Figure 4 – In-grid storage of energy from renewable sources

In-grid storage is becoming a reality through advances in battery technology that can be charged by electricity generated from renewable energy, like wind and solar power. Intelligent battery software uses algorithms to coordinate energy production and computerized control systems are used to decide when to keep the energy to provide reserves or when to release it to the grid. Energy is released from the battery storage system during times of peak demand, keeping costs down and electricity flowing.

This combination of renewable green energy production, in-grid storage and clean EV charging is giving rise to balanced sustainability systems for both energy grids and advanced mobility solutions.

Optimizing Smart Two-Way Charging Between EVs and the Grid

Other important factors are the development of smart-charging and two-way charging capabilities.

Smart charging systems enable consumers to automatically take advantage of lower cost electricity rates for off-peak charging, such as in the middle of the night when grid demand is lower.

In addition, two-way charging enables EVs to serve as additional electricity storage that can actually send energy back into the grids during peak demands or can power the owners’ homes during an outage.

Figure 5 – Two-way charging (or bidirectional charging) enables EVs to power a home

Battery Technology Innovations

While the basic lithium-ion technology used for EVs and grid storage is similar to what is used in a wide range of devices, such as computers, smartphones, tablets, and more, the huge scale needed for power grid storage dwarfs all of these applications.
Over recent years, the experience gained by scaling up Li-ion technology for high volume production of relatively large batteries in EVs has provided valuable insights and solutions that can be readily adapted for in-grid battery storage.

Using technologies such as Interplex’s Cell-PLX™ battery interconnect system, progressively larger batteries can be created by grouping together many individual cells and connecting them efficiently to provide the targeted power levels. The number of cells and power capacity of each cell are the determining factors for total capacity of the battery system.

Cell-PLX™ supports high-speed assembly methods, thereby enabling efficient production processes, lower manufacturing costs, and high-volume operations, while scaling up battery sizes to meet the needs of grid applications as well as various EV categories.

Figure 6 – Overview of Cell-PLX™ battery interconnect system for cylindrical battery cells


Interplex has long been committed to leading in innovation, design, development and production of technologies that will help mitigate climate change and contribute to a greener world and are proud to contribute to the development of large-scale battery storage systems for climate friendly power grids.

Our expert design and engineering teams have been leaders in the creation of battery technologies, such as our Cell-PLX™ battery interconnect systems for EVs, and we are now working closely with the power industry to adapt these technologies for in-grid, high-capacity battery storage systems.

As a long-time innovator and trusted supplier to the automotive industry, Interplex continues to play a key role in developing underlying technologies to enable widespread adoption of EVs. Among these initiatives is our commitment to provide a full range of robust and configurable technologies for improving the cost, performance, lifecycle, and range of next generation batteries that have applicability both for EVs and for storage within new-generation power grids.

Would you like to know more about our solutions for next-gen EVs and power grids?

Discover The Solution That Helped A Leading EV Manufacturer Overcome Design Challenges

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