Just 10 years ago, the magnitude of behind-the-meter distributed energy resources (DERs) at the grid-edge was not materially significant. All that has changed and we’re now at an inflection point: by 2030, we can expect to see roughly 200 million DERs connected globally across innumerable types and brands. As an example, residential solar panel installations are expected to surpass four million by 2023 and electric cars and buses will add over 6% to global energy demand by 2040. While inside the home, more and more thermostats and water heaters are connected to the grid every day. In the United States alone, this results in nearly 200 GW of flexible load, which is 20% of the system peak. The unconstrained operation of these assets presents several challenges — and opportunities — to the grid operator.
The Blindsided Grid Operator
Today, most grid operators simply don’t have either visibility or control of behind-the-meter DERs. This lack of grid-edge situational awareness is increasingly becoming a cause for concern with many utilities grappling with the issue of phantom load. The lack of visibility affects grid operators in both long and short timescales. For example, passing clouds can cause dynamic fluctuations in solar output, causing that customer node to unexpectedly draw or inject power. Without real-time data from, or control access to, the DER itself, the operator cannot plan for this eventuality or dynamically manage the situation — nor can it benefit from the potential value of these inherently flexible DERs.
At the same time, if utilities can find a solution to not only provide visibility but also the capability to orchestrate across distributed resources, utilities can unlock a bankable set of assets. With the right software tools in place, DERs can be aggregated and controlled to provide various grid services — from system-wide load reduction to localized voltage regulation requests — allowing the utility to firm renewable output and mitigate grid conditions such as peak load, congestion, and voltage deviation scenarios. In addition, situational awareness in the form of real-time device telemetry, asset state, and forecasts can allow the utility to dynamically fine-tune grid operations and planning.
The ADMS Versus DERMS Quandary
As DERs proliferate across utilities’ service territories, distribution operators and planners have the most at risk and the most to gain. However, the question remains, what software system — or system of systems — is best suited to unlock value from these DERs? The existing range of systems under their purview do not provide an adequate level of DER access and control. The primary responsibility of the advanced distribution management system (ADMS) is to integrate utility information and systems in order to unify distribution network management, ensuring reliability and optimal operation of the system. ADMSs are also typically purpose-built to monitor and control utility-owned, SCADA-connected equipment, assets, and DERs.
Customer-owned, behind-the-meter DERs are fundamentally different from utility-owned DERs and can be demarcated in several ways:
- Ownership models
- Communication protocols
- Connectivity mediums
- Data fields they relay
- Availability and flexibility
- The steps required to access them
While a number of ADMSs today do have modules that control DERs, these assets are utility-owned and thus fully available and dispatchable. The ADMS is neither built to provide real-time situational awareness of, nor has any level of control over, these behind-the-meter DERs. With a large magnitude and diverse ecosystem of assets to integrate with, utilities will need to look beyond the ADMS for help.
Utilities are increasingly turning to distributed energy resource management system (DERMS) providers, such as EnergyHub, to manage behind-the-meter, grid-edge, and customer-owned DERs. EnergyHub’s Mercury DERMS platform is built to provide three key services to utilities: resource formation, grid services, and situational awareness.
The building block for any DERMS is how the resources are formed. For customer-owned DERs, owners need to be engaged with and ultimately motivated to make their DER available for use by the utility — whether that be heating, ventilation and air conditioning (HVAC), water heaters, solar panels, batteries, or electric vehicles (EVs). EnergyHub leverages its deep technical and business partnerships with device manufacturers to acquire customers through various marketing and engagement channels. As DERs are brought into the DERMS, this customer-centric approach takes into account the inherent unpredictability of consumer preference and behavior in addition to DER-specific capabilities and operational constraints.
Once the resource is formed, the DERMS is able to provide situational awareness and a variety of grid services to the grid operator. Based on the grid service need and objective, the DERMS takes into consideration each DER’s flexibility — including its active and reactive power capabilities along with its location-and schedule-specific availability — before determining which asset or groups of assets are best suited to provide the requested grid service.
The relationship between an ADMS and a DERMS is mutually beneficial. By way of a downstream systems integration with the DERMS, these services may be requested from the ADMS, a configuration that allows the ADMS and the DERMS to play to their respective yet symbiotic strengths to provide crucial visibility and control of DERs as well as empower grid operators and planners to make informed and timely grid management decisions. The unique capability of the DERMS — to be customer-centric, agile, DER-aware, and scale across asset classes — will make the platform an increasingly critical element of fully integrated, holistic utility operations.