By Marco C. Janssen, UTInnovation, the Netherlands
As the world moves toward a low-carbon future, power systems are undergoing a profound transformation.
Renewable generation is rising quickly, battery storage is scaling, EVs are proliferating, distributed solar is becoming mainstream, and digital technologies are demanding vast electrical loads through large data centers. These developments are positive, yet they collide with legacy grid architectures, regulatory inertia, and increasing operational complexity.
Residential solar PV is often viewed as the poster child of the transition as homeowners generate clean electricity, lower bills, and export surplus to the grid. But at high penetration, the picture changes. Distribution networks were built for predictable one-way flows from centralized power plants to loads. With widespread PV, midday power output surges while evening peaks create high demand. This creates reverse flows that can overload circuits. Once distributed generation surpasses a grid’s saturation level, congestion, curtailment, and safety issues arise. Single-phase rooftop systems can also create phase imbalance, harmonics, transformer stress, and unexpected over-voltages.
In many regions the grid cannot absorb all midday solar output, leading to rejected interconnection requests or forced curtailment. Ironically, the push for more renewables is increasingly limited by the infrastructure meant to deliver them. Grid owners are trying to expand capacity, but regulatory and permitting processes often move far slower than the growth of PV and electrification. As a result, some jurisdictions now discourage or restrict new rooftop PV or reduce feed-in tariffs.
Behind-the-meter batteries are often proposed as the remedy to store excess midday PV, and discharge in the evening, thus reducing grid stress. Yet their benefit is limited without coordination. Individually controlled batteries may discharge or charge at the wrong times from a system perspective. Thus, decentralized PV and storage cannot solve network constraints on their own. Regulatory rules, coordination between customers and grid operators, and the speed of distribution upgrades are essential.
Large-scale battery energy storage systems (BESS) offer greater system-level value. They can smooth variability, provide fast frequency response, and defer expensive grid reinforcements. Their rapid control capabilities help stabilize networks operating near physical limits. Grid-enhancing technologies, such as dynamic line ratings and voltage uprating of conductors, also increase capacity faster than building new lines. However, utility-scale storage faces its own barriers. Interconnection queues are long, supply-chain constraints are significant, and distribution-level impacts are nontrivial. Poorly timed discharging can cause local over-voltages or overload equipment. Storage improves flexibility but is not a universal fix. Operators still need better visibility, advanced control, and sufficient physical infrastructure. Without system-wide coordination, network upgrades, smarter operations, and demand-side management, congestion and interruptions will persist.
On the demand side, rapid growth in data centers and AI loads introduces new stress. The IEA estimates global data-center electricity consumption could rise from ~415 TWh in 2024 to ~945 TWh in 2030. Data centers are designed to switch quickly to on-site backup during voltage or frequency disturbances, yet recent failures at major cloud providers show that disruptions can cascade across digital services and the broader economy. Clustering data centers amplifies local network stress, creating single points of failure. Competition for grid capacity among data centers, EV charging, residential loads, and renewables is intensifying. In Europe, utilities already cite grid constraints as a limiting factor for new data-center development. The challenge is dual as we are adding both highly flexible yet extremely power-intensive loads, while generation shifts toward variable renewables supported by storage.
In my opinion, six major issues must be addressed to ensure that the transition proceeds without destabilizing the grid:
1. Lagging grid infrastructure: Upgrades must keep pace with changing supply and demand or the transition will slow and costs will rise
2. Reverse flows and congestion from distributed generation: High-PV neighborhoods need active management, coordination, and sometimes curtailment
3. Storage is not a silver bullet: Batteries add resilience but introduce interconnection burdens and operational complexity
4. Data centers reshape demand: They raise peaks, add congestion, and compete for scarce grid capacity
5. Coordination and flexibility are essential: Demand response, flexible data-center operations, and coordinated residential storage can unlock significant capacity
6. Regulatory, planning, and data-transparency gaps: Interconnection delays, unclear grid-capacity data, and outdated business models hinder progress
Ultimately, the energy transition is not just about more solar panels, batteries, or smart meters. It requires a grid designed for the 21st century to support millions of prosumers, flexible loads, variable renewables, storage, and rapidly growing digital demand.
If grid bottlenecks remain unresolved, investments in renewables will be underused, PV may become a nuisance, storage will disappoint, and data-center growth will stall. Smart policy, proactive planning, transparent data, and aligned incentives will determine whether clean energy is enabled or constrained by outdated infrastructure.
Biography:
Marco C. Janssen is the CEO of UTInnovation and the former VP of Operational Excellence at TAQA, Digital Grid Leader for Latin America at EY and Director of the Smart Grid PMO at DEWA. He received his BSc degree in Electrical Engineering from the Polytechnic in Arnhem, Netherlands and has worked for over 33 years in the field of Power and Water O&M, Digital Transformation, Protection, AMI and Distribution and Substation Automation. He was a member of IEC TC57 WG 10, 17, 18, 19, the IEEE PES PSRC and CIGRE B5 and D2 WGs. He was the convenor of D2.35 and editor of the Quality Assurance Program for the Testing Subcommittee of the UCA International Users Group. He holds one patent, is the author of the book titled “Recreating the Power Grid”, has authored more than 53 papers, is co-author of 4 Cigre Technical Brochures and 2 books on SmartGrids and Electrical Power Substations Engineering and is the author of the “I Think” column in the PAC World magazine.
