by Robert MacDonald: As individual states across the U.S. work towards increasingly ambitious net zero emissions targets, the logistics of how these targets can be achieved and where investment should be made is at the forefront of decision-makers’ minds…
To date, considerable efforts have been made to look at solutions that implement more renewables and clean energy into a modern and sustainable electricity system – and electric vehicles (EVs) have an important role to play.
EV adoption has been accelerating in the United States – by 2030 an estimated 18.7 million EVs will be on U.S. roads, up from 2 million in 2020. An increasing portion of EVs will be composed of full battery electric vehicles (BEVs), leading to significant increases in electricity consumption – estimated to grow from 6 to 53 billion kilowatt-hours (kWh) per year by 2030. At the same time, EV charging infrastructure remains limited, with an estimated 9.6 million EV charging stations needed to meet the growing demand.
The slow rollout of EV charging infrastructure can be attributed to a combination of investment certainty, finance and incentives but also physical system limits around today’s grid infrastructure and a lack of interoperable technologies to understand and manage charging. Today’s electrical grid has limited capacity to supply significant new EV charging demand without requiring extensive equipment upgrades, such as power transformers and circuits.
Paradoxically, existing grid infrastructure experiences overall low utilization rates, or load factor, from EV charging due to short-duration, high-demand usage patterns. For EV supply equipment (EVSE) developers, EV consumers, and utility customers the potential over-build and underutilization of grid assets can result in high costs that prevent or delay expansion of charging infrastructure.
Managed EV charging could address both these issues.
Three essential elements are needed to allow the rapid build-out of EV charging infrastructure:
- Connectivity to EV chargers: Today’s EV charging infrastructure has little or no connectivity for data collection and charge management. Public charging is dominated by charging network operators (CNO) that work on closed, private networks while workplace and home chargers are largely stand-alone installations, unconnected to any network. Operators of energy markets, transmission networks, and distribution networks will require pathways to communicate and manage EVSEs to maximize value for EV customers, providing availability and affordability, while maintaining safety and reliability. There are a number of connectivity and control technologies that can be deployed effectively to meet this challenge.
- Real-Time Grid Awareness & Coordination: As EV charging increases, the existing grid infrastructure will become increasingly constrained. Grid operators will require enhanced visibility of grid power flows and awareness of EVSE activity to ensure system safety and reliability. At high penetration levels, EV charging demand will need to be managed in real-time against grid constraints; for instance, voltage levels or thermal overload.
- Smart Charging Methods: New, intelligent methods of EV charging can provide broad benefits to consumers. Consumers with flexible charging needs can lower charging costs by taking advantage of times with low energy demand or excess energy production; for example, by charging at nighttime or when solar or wind power production is high. At the same time, the rollout of EV charging infrastructure can be accelerated if charging can be managed and coordinated alongside grid operations, allowing for faster interconnection and permitting. The technical and commercial solutions required are now only starting to be trialed and implemented.
Meeting the Challenge
Distributed energy resource management system (DERMS) software can help accelerate the build-out of EV charging infrastructure, by enabling managed charging solutions.
A DERMS platform acts as the central coordinating entity that manages, automates, and optimizes EV charging across the grid. To start, DERMS enables end-to-end connectivity between the operator and the EVSEs by communicating with private charging network operators as well as disparate, stand-alone EVSE installations. Not only must DERMS have the flexibility to interface through various telecommunications pathways – such as broadband, cellular or private networks and proprietary or standard communications interfaces — they must also manage many different monitoring and control signals in order to aggregate EVSEs into potential demand reduction resources.
Once EVSEs are linked, DERMS can be used to implement a variety of intelligent charging programs across the entire connected fleet. These include basic programs such as scheduled charging (e.g. target charging from 12am to 6am), shared charging (e.g. demand shared across multiple charging stations), and coordinated charging (e.g. charging during periods of excess on-site solar production). But they also entail more sophisticated programs which employ elements of forecasting and optimization, such as real-time management against grid constraints or price signals.
A managed EV charging strategy using DERMS can bring significant benefits for grid infrastructure. DERMS can be integrated with operational systems such as Energy Management Systems (EMS), Distribution Management Systems (DMS), and utility SCADA to obtain real-time grid telemetry, identify potential grid constraints, and take actions to manage EV charging levels. A properly implemented DERMS system should be able to monitor EV charging demand, calculate potential for demand reduction, and coordinate the reduction in line with the grid’s physical limits.
At the same time, DERMS can also manage the complexities of coordinating and dispatching a large number of EVSE with different control points; this may involve requesting demand reduction of a fleet of EVSE from a charging network operator, directly controlling individual EVSEs, or a combination of the two. Grid operators at distribution and transmission levels with increased visibility and control of EV charging will allow for expanded grid hosting capacity for new charging stations, increased utilization of existing grid infrastructure, and minimized grid upgrade costs – all while maintaining system safety and reliability. This creates benefits for EVSE developers in more grid hosting capacity and quicker interconnections, at lower cost.
For the broader energy system, DERMS can be integrated to manage reduction in demand and utilize market pricing signals to coordinate optimal EV charging times. The benefits include supply/demand alignment, reduced resource requirements, and lower energy prices. As the system incorporates more renewable generation, DERMS can also incorporate weather forecasts that anticipate times of high renewables availability in coordination with EV charging needs, providing benefits of lower charging costs while maximizing the use of low carbon electricity.
A well-coordinated EV charging strategy ultimately benefits EV consumers through lower charging costs, accelerated deployment of EV charging stations, and increased environmental benefits enabled by DERMS technology.
Making EVs mainstream
If governments are to achieve net zero targets, investment in EVs is critical. While progress has been made to encourage the uptake of EVs, more can still be done.
To create a sustainable EV charging infrastructure, increasingly intelligent operational systems such as DERMS must be put in place that are flexible and adaptable to the needs of the fleet operators, grid operators and EV users. By implementing managed charging solutions, not only will EVSE operators be able to collect valuable data to inform future solutions, but by pairing this with renewables, they can create new flexible tariffs and implement a variety of new incentives. In turn, this will boost the market and make EVs and the necessary smart charging infrastructure a more attractive investment.