Load Management and Balancing in EV Charging

It’s crucial for EV charge point operators to keep these loads properly managed and balanced to prevent overloading the electrical infrastructure, which can lead to outages, reduced charging speeds, or even damage to the grid. For example, California has implemented load management standards to help reduce greenhouse gas emissions and strengthen the resiliency of the electricity grid.

Proper load management ensures that power is distributed efficiently across all charging points, maintaining site reliability while also reducing operational costs by avoiding peak demand charges and optimizing energy usage. This not only keeps charging reliable and cost-effective across EV fueling stations, fleet depots, and other commercial properties but also supports the stability of the broader electrical grid.

What is EV charging load management and balancing?

Load management is about controlling and optimizing your distribution of electrical power across site devices to avoid overloading the grid or exceeding capacity limits. This is particularly important on sites where multiple high-power devices, such as EV chargers, are drawing electricity simultaneously. Load balancing involves distributing the available power among different systems in a way that ensures efficient and reliable operation. While load balancing is related to load management, it focuses more on the real-time distribution of power.

Load management ensures that the total power demand from all charging electric vehicles does not exceed the capacity of the electrical infrastructure, such as the local grid or a building’s power system. Some load management systems allow prioritizing certain electric vehicles based on battery level, charging speed, or user preference. For example, an EV with a low battery might be charged faster than one with a higher battery level. Load management can also help optimize charging times to align with time-of-use (TOU) pricing and off-peak hours when electricity rates are lower to reduce costs for both operators and customers.

By the same token, EV charging load balancing involves adjusting the power supplied to each EV charger based on the overall load, ensuring that all vehicles receive an optimal charge without exceeding the site’s power capacity. Load balancing also prevents any one charger from consuming too much power, which might otherwise cause other chargers to operate at reduced efficiency or trigger grid balancing issues. Balancing loads helps prevent scenarios where the combined power draw of all charging vehicles could overload the electrical infrastructure, leading to potential outages or damage.

How does static compare to dynamic load balancing?

Load balancing can be performed in two ways: static, in which power distribution is fixed, and dynamic, in which power is allocated based on real-time demand and usage patterns.

Static load balancing

Static load grid balancing works by distributing the available electrical power from the grid evenly across all EV chargers based on pre-determined site settings. Each charger is given a fixed portion of the total available power, regardless of the number of vehicles being charged or their individual power requirements. For example, if an EV charging site has a total power capacity of 100 kW and ten charging stations, each charger might be allocated 10 kW.

Dynamic load balancing

Dynamic load balancing, in contrast, is a “smart” approach that requires advanced management systems to adjust power distribution in real-time based on the actual demand and usage patterns of the charging stations. This involves continuously monitoring the power requirements of connected electric vehicles and adjusting the distribution of available power to ensure optimal charging and reduce energy costs. For instance, if one vehicle is nearing the end of its charging session and requires less power, the excess power would be redistributed to another vehicle that needs more.
Each approach has its pros and cons. Choosing between static and dynamic load balancing depends on various aspects of your EV charging business.

What are the different approaches to distributing electricity through EV load management?

Load-sharing EV chargers can provide electricity to stations either by distributing power equally or with a first-in, first-charged approach.

Equal distribution

With an equal distribution approach, available electricity is divided evenly among all active charging stations. This approach ensures that every EV connected to a charger receives a proportional share of the power, regardless of when they begin charging. For instance, if a site has 100 kW of available power with ten vehicles charging, each one would receive 10 kW. This method is straightforward and fairly allocates power to all users, ensuring that no single one consumes all available power.

First-in

On the other hand, the first-in method gives priority to vehicles according to the order in which they connect to the charging stations. The first vehicles to plug in get all the available power so that other vehicles receive whatever is left. Each new vehicle potentially receives less power than those already charging. Take a vehicle that’s already plugged in and drawing 50 kW from a site with a 100-kW capacity. If a second vehicle connects, the remaining 50 kW would go to the second vehicle.

This method can be advantageous when it’s important to prioritize certain vehicles, especially those that have been waiting the longest or connected first. It can also be beneficial during peak times or in high-demand locations where charging stations are in constant use. Still, it could result in longer wait times for vehicles that connect later, especially if the first vehicles draw a lot of power for extended periods of time. This can create inefficiencies, especially if the first-in vehicles aren’t in dire need of a fast charge.

So, while equal distribution promotes fair and uniform power allocation, the first-in method offers a way to prioritize vehicles based on their connection time, which is useful in high-demand scenarios. EV charge point operators may opt to use a combination of both approaches to realize the benefits of equal distribution and first-in methods. For example, a charging site could allocate a baseline level of power equally to all connected vehicles, and then prioritize additional power base on the order of connection or specific user needs. This approach allows for more flexible and efficient use of the site’s power resources, balancing equality with the practical need to prioritize certain vehicles.

It’s important to understand the needs of the users and the site’s charging capacity when selecting the best load management strategy for your site to guarantee efficient, reliable and user-friendly EV charging.

Benefits of load management for EV charge point operators:

Load management allows site operators to take control of their EV charging and experience a number of benefits.

• Continuous service: Load management optimizes infrastructure by making sure that it’s used efficiently, potentially avoiding the need for costly upgrades. With EV charging load management, operators can be assured that they are making efficient energy usage of available power capacity by distributing the charging load evenly across stations and infrastructure for consistent operation.
• Satisfied customers: Allocating power resources based on real-time demand ensures that charging stations are effectively utilized. Drivers of electric vehicles enjoy a more reliable and consistent charging experience with less congestion or delays.
• Lower costs and higher revenue: Minimize operational costs by avoiding peak demand charges and optimizing energy use according to real-time needs and electricity pricing. Load management systems also enable peak shaving to reduce your network’s electricity needs during peak demand periods for lower demand charges, while allowing you to participate in utility programs for additional revenue opportunities.
• Support grid stability: Balancing loads on your EV charging site helps contribute to the overall stability of the grid by managing demand from an increasing number of EVs, especially during peak usage times.

How do smart energy management systems optimize EV charging load management?

An EV load management system is an advanced technology designed to manage the charging of EVs with a goal to optimize energy usage and minimize strain on the electrical grid. They typically consist of both software and hardware components working together to effectively direct charging stations.
The software component is the brain of the EV load management system, including algorithms that determine when and how to charge electric vehicles based on various aspects. The software may also include user interfaces for EV owners to monitor and control charging sessions remotely, as well as communication protocols to interact with utility systems or other components of the electric grid. Hardware components can consist of charging stations, power meters, sensors, controllers and communication modules.

EV load management systems help keep your operations running and profitable. Through automatic load management, the system communicates with individual EV chargers to enable load sharing by intelligently distributing the power demand by EV charging status, electricity requirements and available capacity. Optimizing available power resources ensures efficient and reliable operation.

Load management systems constantly monitor the energy consumption of each EV charger as well as overall power availability. Based on the information gathered from each EV charger, the load management system dynamically allocates power to ensure that your overall demand does not exceed the capacity of the electrical infrastructure. It may reduce the charging power of some stations temporarily to accommodate others to prevent overloading the grid. The system aims to balance the load across multiple charging stations to make the most out of available power resources.

Based on your customized site goals, the system can assign priorities to different EVs based on various factors. For example, an EV with a low battery level may be directed to charge first. Load management systems can also incorporate smart scheduling algorithms to coordinate charging sessions based on electricity prices, grid congestion and renewable energy availability. This ensures that EVs charge when electricity is available and cheap.

For example, Sparkion enables customized, automatic load management. Sparkion’s SparkCore™ on-site energy management system enables real-time power monitoring to control your EV charging network for optimal economics and an ideal customer experience.

Sparkion’s customizable AI-driven charging algorithm uses calculations to inform dynamic load management by determining how much energy to pull from the battery or the grid to meet EV load while staying within the limits of your charging and site power strategy. Our granular sub-second site measurements allow EV charging load balancing according to your business model, whether it’s based on charging urgency, energy pricing or prioritizing VIP customers.

Benefits of EV charging load management with Sparkion

• Controlling EV charging
• Monitoring the site in real-time
• Customizing power allocation
• Ensuring reliable operations
• Keeping customers satisfied
• Reducing costs
• Increasing revenue