How Duke Energy is optimizing its grid to handle more EVs

As more customers opt for EVs, smart investments and advanced technology are readying the grid

From fleets of electric school buses to your neighbor’s new Tesla, the electric vehicle (EV) market continues to heat up. One in four new-vehicle shoppers are “very likely” to consider an EV for their next purchase, according to a J.D. Power 2023 U.S. Electric Vehicle Consideration Study.

Not only do these vehicles offer improved range, a wider selection of models and better performance from prior versions, but recent tax credits are also making EV ownership more affordable.

As manufacturers and the electrification transportation sector prepare for an influx of EVs on U.S. roadways, utilities are readying their electric grids – ensuring customers have the power needed to charge those vehicles.  

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Duke Energy is making data-driven investments to improve reliability, strengthen the grid, expand technologies and provide customers with the information they need to make smart energy choices and save money.

So, can the grid handle the predicted wave of future EVs?

The short answer is yes, said Jay Oliver, managing director of Energy Storage and Grid Development at Duke Energy. With nearly 30 years of experience in transmission, distribution planning and operations, Oliver helps shape the company’s grid readiness strategy.

“For starters, this type of strain on the grid isn’t new. These big booms in load growth have occurred before,” Oliver said. “One of the best examples – the advent of air conditioning systems – came as homes began to electrify.”

The electrification of vehicles is expected to be another big boom in energy. Over the next 15 years, Duke Energy is forecasting energy demand to grow at an average annual rate of 2.5% – about 40% of which is expected to come from greater EV adoption.

The best way to meet this load growth, Oliver said, is to manage the demand on the grid, avoiding energy consumption that happens all at once – in early evening, for example, when many people get home from work or school.

Through financial incentives, the company aims to shift demand on the grid to times of day when less energy is used, which is important since over 1.5 million EVs are expected to be on the road in Duke Energy’s service areas by the end of 2030.

Faster forecasting, smarter investments

Duke Energy is also focused on the bulk power system, facilities and control systems necessary to operate the interconnected electric energy transmission network. In fact, the company plans to invest $75 billion over the next decade on grid modernization alone.

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Shifting electricity away from times when customer demand for energy is high – known as “managed charging” – is one of the best ways to meet load growth and manage demand on the grid.

Determining where – and how – the grid should be updated to meet the needs of customers now and decades into the future requires the ability to process the billions of data points around energy usage coming off the grid at any given time.  

To help do this, Duke Energy built a suite of more than a dozen grid-planning tools known collectively as Intelligent Grid Services. The applications fall into three major categories: data cleanup, forecasting and grid planning.

One application can project hour-by-hour needs at the circuit level for the next 11 years. Another takes those data inputs and offers a series of suggestions for grid improvements at different price points to solve for that projected load. Another application estimates how much load can be accommodated on the distribution system without impacting power quality or reliability.

Used together, the suite of tools helps forecast where needs will be greatest. It also recommends grid solutions to meet those needs.

Not only are EVs cleaner for the planet and environment, but they help save on fuel and maintenance costs. Today’s models can also drive farther on a single charge.

In 2022, Duke Energy announced a multiyear collaboration with Amazon Web Services (AWS) to help optimize these tools. As the in-house tools are moved to the AWS cloud, AWS is building out cloud technologies to meet the needs of Duke Energy’s grid-planning applications – and those that other utilities will build in the future.

More than 18 months into the collaboration, the results have been powerful. What used to take around six weeks (using traditional on-premises IT hardware) happens much quicker now that the tools are on the cloud, said John Pressley, director of clean energy strategy and engineering at Duke Energy.

“By using the advanced cloud technologies AWS is developing for our applications, we can crunch those same algorithms in hours, not weeks,” Pressley said. “And our goal is to cut that time down to minutes.”

As a result, the company can make smarter decisions faster about where and how the grid should be updated to meet the needs of customers now and in the future. 

The art of ‘managed charging’

Duke Energy is also working with EV charging companies to understand where they are installing supercharging stations, which are not as flexible as residential chargers, and working with logistics operators to coordinate charging of commercial fleets.

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Customers who participate in voluntary-managed charging programs can plug in their vehicle when it’s convenient. The system will automatically initiate the charge at an off-peak time.

On the residential side, to manage and shift peak demand, the company has launched several innovative EV customer programs, including EV Off-Peak programs in Florida and Indiana. Eligible customers who have a Level 2 EV home charger receive a credit either monthly or quarterly if they charge during off-peak hours. 

In North Carolina, which has a goal of 1.25 million EVs by 2030, Duke Energy is supporting that goal by launching a pilot program that offers a fixed rate of $19.99-$24.99 per month, depending on the service area, for at-home charging. In exchange for the fixed rate, customers are expected to charge during certain hours and allow Duke Energy to pause charging as needed up to three times per month.

“Vehicles are often parked for much longer than the two or so hours it takes to charge, which gives us the flexibility to initiate home charging during off-peak hours, when less customers are using electricity,” Oliver said. “A major supercharging station is less flexible for the utility in that it’s designed to serve customers immediately.” 

The insider term for this is “managed charging,” which just means shifting electricity away from times when customer demand for energy is high. It’s ideal for customers who wish to ‘set it and forget it.’

Voluntary-managed charging programs are designed to help balance demand on the grid with little inconvenience to Duke Energy customers. They’d plug in their vehicle as they would normally, when they get home from work, for example, and the system would initiate the charge at an off-peak time. 

“Enrollment in our EV Off-Peak programs has exceeded expectations,” Oliver said. “Customers are doing exactly what we hoped they would, so that’s a positive sign.”

Through data-driven investments, advanced technology and a growing portfolio of innovative customer programs, Duke Energy continues to make strides in optimizing its grid to handle the increasing demand for cleaner vehicles – ensuring a sustainable and reliable future for EV adoption.