Distributed energy resources are reshaping the sustainability landscape. Grid operators must adopt intentional, hierarchical architectures to reduce complexity, ensure reliability and unlock the full promise of clean power. Grid energy controllers can help.
Learning objectives
- Understand the role of distributed energy resources (DERs) in new clean energy initiatives.
- Learn about a new hierarchical architecture based on grid edge controllers that act as DER gateways.
- Controlling the modern grid system invited cybersecurity concerns.
Clean energy insights
- Distributed energy resources are a core element of a shift toward smart grids and clean energy.
- New architecture must be implemented to enable DERs on the distribution side of renewable energy.
- A new hierarchical architecture based on grid controllers could be a solution.
Modern society has an almost insatiable appetite for electricity. Electric cars, data centers and more increasing amounts of electricity from the grid. As the demand on the grid increases, people, companies and even governments call for an increase in sustainable production of that electricity, putting even more pressure on power generators to not only increase output but to do so in new ways. Grid edge controllers and increased attention to cybersecurity are helping.
A key element of the response to this global shift has been an evolution of the power grid. The traditional model of siloed generation and distribution, with each team staying in its own lane, has begun to shift. Distributed energy resources (DERs) have been a core element of this shift, with renewable energy generation assets beginning to appear on the distribution side of the power architecture. Rooftop solar installations, community battery and even small, private wind generation sites and more make up these DERs, which have become an important part of the overall energy generation mix.
Bringing DERs into the energy mix is not something that can be done thoughtlessly. Increased options and flexibility also mean increased complexity, so new architectures must be implemented with an intentional strategy. The traditional grid control center with a distributed energy management systems (DERMS) capable advanced distribution management system (ADMS) is still a key player, but if teams aren’t careful, the addition of modern, distribution-side DERMS can quickly create unwieldy architectures, reliability issues and cybersecurity concerns.
However, there is an emerging solution — a hierarchical architecture based on grid edge controllers acting as DER gateways. Such a system provides local aggregation points and control at the edge for high-speed DER applications, and it seamlessly integrates into grid management and DERMS solutions for continuous centralized control and visibility.
Investigating a new DER architecture
The grid edge controller/ADMS architecture is hierarchical. The highest level of the architecture is the ADMS. This uppermost level provides distributed energy management functions from the central control location. Grid operators will still use the ADMS to orchestrate and conduct operations across the grid.
However, instead of connecting all the high-speed, lower-layer assets directly into the centralized control, the ADMS is instead connected to grid edge controllers that act as DER gateways. Each gateway can communicate with multiple DERs in the field and then aggregate and add context to collected data for presentation of information back to the ADMS for visibility and management functions. Everything is connected to the ADMS via a standard, secure protocol, ultimately abstracting away the diversity, capabilities and vintage of the DERs so grid operators focus on orchestration rather than configuration (see Figure 1).
Creating a new DER architecture while combating complexity
The greatest challenge with DERs is that they are often not traditional, transmission-connected entities. Often, DERs — particularly renewable energy assets like solar — are smaller generators connected on the distribution side. In fact, many renewable energy DERs are not managed by the utilities but rather controlled behind the meter by an end user or an aggregator, making control and coordination complex.
Utilities need visibility into these remote assets, and they need to be able to see their effects and manage their generation throughput. They typically do so by using a digital grid management DERMS application. However, DERs come in a wide array of sizes, formats, manufacturers and vintages, making it difficult to directly connect them to DERMS in the ADMS. As the grid continues to grow, it quickly becomes difficult or impossible to manage all those connections and devices separately. Teams need a control hierarchy that allows them to group the higher-speed, lower-level assets together for easier management.
Grid edge controllers operating as DER gateways aggregate all DER communications — regardless of technology or vintage — together to provide a consistent interface back to the digital grid management solution for easier communications, management, visibility and control of assets. Moreover, teams can allow grid edge controllers to perform control functions locally and aggregate the reporting back to the grid control center’s ADMS to cut down on bandwidth requirements.
Ultimately, the DER gateway architecture provides effective plug-and-play capability between the individual DERs and the ADMS, cutting complexity and letting operators focus on operations, instead of complex engineering and maintaining connectivity.
Enhancing resiliency and reliability with grid controllers
One of the other benefits of a modern grid architecture built on grid edge controllers functioning as DER gateways is increased resilience and reliability. With a traditional architecture, when there are outages, teams must attempt to fix issues from within the central system. If everything is tied into the central system via a complex web of custom connections between DERMS and a variety of different DERs, when a failure occurs, the team must first identify the source of the failure within the system and then diagnose it, slowing repair and increasing the risk of creating additional problems.
In contrast, in a hierarchical system using DER gateways, system reliability is improved. When the assets on the lowest layers fail, the ADMS can work around that single connection to the failing DER gateway until it is resolved, reducing points of failure and increasing uptime, along with the ability to deliver adequate power.
Resiliency is further increased by the fact that the grid edge controllers can run semi-autonomously. If a weather event or other issue severs communications to a DER gateway, the grid edge controllers can keep those assets running safely until communication can be restored. Ultimately, these new architectures add more redundancy into the system, while simultaneously simplifying connectivity and visibility and standardizing for increased scalability.
Ensuring cybersecure connectivity
One of the key concerns with controlling the modern grid is cybersecurity risk. The ADMS is likely very cybersecure, but DERs often have limited or no cybersecurity provisions. If those insecure assets are connected directly to DERMS in the ADMS, communication between the asset and the central control is subject to cyberattack. All a bad actor needs to do is get between the DER and the ADMS to cause problems.
Fortunately, it is possible to embed cybersecurity agents in DER gateways, as they tend to have more modern processing technology than legacy DER systems. Embedding cybersecurity functions, such as deep packet inspection, inside the gateways helps ensure all communication across the grid is secure. Moreover, incorporating cybersecurity into the DER gateway means that updates only need to be performed on the gateway side, making it possible to continually apply updates and patches to support increased security for the wide variety of assets at lower layers, without risk that a change will interfere with the ADMS.
DERs fuel a more distributed energy future
As communities around the globe continue to add renewable energy DERs — in parallel with associated increases in production on the distribution side of the grid — power companies will need more flexible, scalable architectures to support that evolution. A hierarchical architecture built from an ADMS connected to grid edge controllers serving as DER gateways will dramatically reduce the complexity that stalls expansion, complicates operations and introduces cybersecurity risks.
Though the grid will continue to evolve and nobody can predict what the smart grids of five to 10 years from now will look like, the technologies exist today to prepare for the scale ups and scale outs that will be necessary to support that shift. It is not too early to start preparing for the future of energy production and distribution and a trusted partner can help.
