This shift has important implications for developers facing grid constraints, increasing reliability requirements, and rapidly changing AI workloads. Microgrids offer a strategic infrastructure solution.

A data center microgrid combines on-site power generation and energy storage that can operate in parallel with the grid or independently in island mode. In this context, “microgrid” refers to the power supply configuration, not the size of the system.
The need for this flexibility stems from three challenges that increasingly shape AI data center power demand:
Securing access to power has become a defining constraint for data center development, directly affecting project viability and timelines.
According to BloombergNEF, data centers in the U.S. could account for about 20% of the country’s electricity consumption in 2035, up from 5.9% today [1]. This rapid growth is pushing developers away from historically dominant markets toward secondary regions with available grid capacity.
For projects facing delayed or constrained grid access, on-site generation within a microgrid offers an alternative. These systems can combine fossil fuel generation, renewables, battery energy storage, and small modular reactors. As grid power access improves, facilities can transition to hybrid systems that balance reliability, economic factors, and operational flexibility.
How the various generation options compare is explored in The Digital Merit Order [2].
The quality of supplied power is especially critical for computational loads. Traditional data centers rely on utility power supported by Uninterruptible Power Supply (UPS) systems and back-up generators that are often fossil fuel based. While effective for maintaining uptime, this configuration can create broader system impacts during grid disturbances.
In 2024, the North American Electric Reliability Corporation (NERC) reported an event in Virginia in which a 1.5 GW load dropped from the grid within 82 seconds following a transmission line fault [3]. This kind of abrupt change in demand can threaten power system stability, which depends on the real-time balance between generation and consumption. Microgrids help mitigate these impacts by enabling on-site generation to operate continuously alongside the grid rather than functioning solely as emergency back-up. When adequately sized, they can also support island mode operation, allowing facilities to remain insulated from grid disturbances altogether.
AI data center workloads create power demand profiles that are far more variable and less predictable than typical loads. AI workloads generally fall into two power profiles: training mode and inference mode (see Table 1).
Table 1: How AI training and inference create different power demand patterns
|
AI workload mode |
What it means |
Power demand pattern |
Why it matters for the grid |
|---|---|---|---|
| Training | Building or improving the AI model using large computing clusters | High and sustained demand over long periods, with some short-duration fluctuations | Requires large blocks of reliable power and can create stability concerns when loads shift |
| Inference | Running the trained model to respond to user requests or generate outputs | More variable demand that rises and falls with usage | Creates less predictable load patterns, making power quality and grid planning harder |
Beyond the broad demand patterns shown in Table 1, AI training workloads can also exhibit short-duration fluctuations (Figure 1) [4].

At the facility level, these load variations can translate into similarly large power fluctuations as shown in Figure 2. In a worst-case scenario, demand changes of up to 1.9 per-unit (95 MW) per second over approximately 250 milliseconds are observed during the ramp-up.

Sizable load fluctuations resulting from large-scale AI training can create grid stability concerns in two ways:
Similar load characteristics have long been associated with electric arc furnaces and other large metallurgical facilities. Some of these facilities have been operating as microgrids for power availability and reliability reasons. In addition, they often employ advanced power/voltage control systems, including Smart Predictive Line Controllers (SPLC), static watt compensators, static VAR compensators, synchronous condensers, or static synchronous compensators [5]. For example, Figure 3 illustrates how SPLC technology smooths power fluctuations in an electric smelting furnace, enabling stable operation within a ~100 MW microgrid. Similar technologies may have to be adopted to address the fluctuating loads of the AI data centers.

Microgrid configuration offers more freedom in handling the variability as fast response on-site generation can provide spinning reserve, while short-term duration energy storage or other power quality mitigation technologies can smooth the power profile presented to the grid and support the voltage and frequency.
Power is becoming a defining factor in where data centers are built, how they’re designed, and which AI workloads they can support. The grid was engineered around predictable demand patterns. AI data centers behave differently. They are massive, geographically concentrated, and capable of rapid, significant swings in load. Microgrids and on-site power generation offer a practical way to address these challenges (see Table 2).
Table 2: How microgrids help manage AI data center power challenge
|
Power supply challenge |
Grid-supplied AI data center |
Microgrid powered data center |
|---|---|---|
| Grid capacity bottleneck | May require heavy utility infrastructure upgrade, delayed deployment | On-site generation can fast track development |
| Grid power quality | Needs adequately sized UPS and back-up generators Can negatively impact grid stability when power is suddenly switched to back-up mode |
Reduced impact on the grid due to use of on-site generation |
| AI workload variability | Needs compensation for MW and MVAR fluctuations | Reduced impact on the grid due to use of on-site generation, energy storage, power quality mitigation equipment, or a combination of all |
Projects facing capacity constraints, long interconnection timelines, or highly variable workloads should treat on-site generation and microgrid solutions as a primary rather than supplemental approach to design.
Applying lessons from industrial power systems—where large, complex loads such as electric arc furnaces have long required active management—can help create more resilient and flexible data center power supply solutions. Hatch brings decades of experience designing power delivery systems for large, variable industrial loads. That perspective can help AI data center developers integrate site planning, power supply, reliability, microgrid design, and operational controls into one power strategy.
Developers that assess power strategy early will have more options, fewer schedule surprises, and greater control over reliability and operating performance.