Modernizing Flow-Control Infrastructure Unlocks the Full Potential of Pumped Storage Hydropower

Urban populations are growing, data centers are popping up all over the country and the automotive industry is electrifying vehicles. Despite surging demand, the country’s capacity is constrained by the intermittency of renewable generation. Many believe lithium-ion batteries are the solution to the problem. They’re wrong.

Industry professionals need only turn their attention away from chemical battery solutions for a moment to realize the potential of pumped storage hydropower. This technology may seem dated in comparison, but that isn’t anything digitalization can’t fix. By modernizing hydropower, the country could lead the clean energy transition.

Meet the Original Gigawatt-Scale Water Battery

Industry professionals can agree that electricity demand will soon outpace supply. However, they are divided on the best generation and storage methods, as there are many viable solutions. Among all options, pumped storage hydropower is the most underrated.

Gravity-fed flow between two reservoirs generates electricity. During periods of low demand, water moves uphill, converting electric energy into potential energy, which is stored in an upper reservoir. Since this hydroelectric power storage system can keep and release energy as needed, it acts as a giant “water battery.”

Why the Obsession With Chemical Batteries?

The industry is obsessed with battery energy storage systems, which are becoming increasingly advanced and more affordable. However, chemical batteries cannot compete with existing long-term, large-scale power storage infrastructure.

While chemical batteries are rapidly declining in price, they still cannot rival pumped hydropower for long-term and large-scale storage. Pumped storage hydropower accounts for 99% of global storage energy volume and 96% of global storage power capacity. Although it does not receive the same acclaim as its lithium-ion counterpart, it is abundant and extremely efficient.

Even among other renewables, hydroelectricity is extremely popular. As of 2025, it is responsible for 60% of all green electricity produced. Unlike solar and wind, it can store and release power on demand. Thanks to turbines, tunnels and rotors, it does not need to rely on nature’s whims to generate energy by moving water.

Hydropower Solves Renewable Intermittency

Water can act as a battery, too. Hydropower is among the oldest and most reliable grid-scale storage technologies. It accounts for the vast majority of active energy storage installations and has a considerable global installed capacity.

Since reservoirs and dams are not considered “high tech,” they are often overlooked during conversations about the solution to surging electricity demand. Despite this, they are among the most efficient technologies in existence.

According to the U.S. Energy Information Administration, this method returns approximately 80% of the electricity it stores. As the country’s share of intermittent solar and wind technology increases, reliable energy storage will become increasingly crucial for meeting demand amid supply fluctuations.

The Modern Grid Demands Scalable Stability

With electricity demand rising, grid stability is becoming increasingly important. Pumped storage hydropower is ideal for addressing renewable intermittency because it returns most of the energy it stores, and it is strategically located.

A 2026 report from the National Hydropower Association asserts that expanding hydropower could help meet exponential increases in electricity demand driven by data center proliferation. It identifies more than 60 megawatts of proposed pumped storage capacity in the U.S. development pipeline. Around 85% of these projects are located in the Western U.S., where the widely recognized “data center capital of the world” is located.

The country can sustainably add 60,000 megawatts of electricity generation capacity to the grid, most of which is near high-demand areas. This would lower the total required investment into electricity distribution infrastructure, making utility-scale renewables feasible. With demand so close to the source, providers could scale to meet it more easily.

As one of the most common and well-established energy storage technologies, pumped storage hydropower is vital to grid reliability. It remains the dominant technology for long-duration storage, making it invaluable to the evolving grid.

Untapped Potential Locked Behind Aging Dams

Hydroelectric dams will need to store and release energy via hydropeaking, which involves quickly and frequently adjusting water flow to meet fluctuating electricity demand. Unlocking the gigawatt-scale potential of existing infrastructure relies entirely on upgrading mechanical flow-control systems to handle rapid, daily cycling.

Compared to nuclear, natural gas and coal plants, hydropower plants can ramp electricity generation up or down extremely quickly. Their high degree of flexibility enables them to compensate for the intermittency of renewable energy. However, their ability to respond to demand fluctuations may be hindered by aging equipment.

Engineers must modernize hydropower by upgrading flow-control mechanisms to enhance performance and resilience. Increasing facilities’ capacity relies entirely on replacing aging, manual systems with digital, automated or intelligent technologies.

Upgrading is a necessity, not a luxury. The consequences of relying on outdated systems are far-reaching. Aging hydraulic systems are prone to breakdowns, which lead to casualties. From 1965 to 2020, each dam failure resulted in up to 98 deaths and numerous injuries. While the cost of each life is immeasurable, stakeholders can easily calculate downtime and repair costs.

Moreover, each failure undermines public confidence in pumped storage, thereby adversely affecting the future of hydropower generation. While this technology could be transformative, stakeholders, utility companies and industry workers need to know it is as safe as it is efficient.

The True Cost of Modernizing Existing Dams

Standardizing and modernizing hydropower flow control architecture involves interconnected and internet-connected technologies. Sensor arrays enable remote monitoring, allowing personnel to identify and address minor issues before they escalate. Digital twins can create a virtual copy of turbines and rotors.

With real-time data, dam operators can see how their changes affect operations as soon as they are implemented. This level of insight can help them reduce operational costs and eliminate unnecessary maintenance, saving time and money. While downstream savings are likely, upgrading infrastructure will require a considerable capital investment.

In the United States, every region has some form of pumped storage hydropower. The country has 22 gigawatts of electricity-generating capacity and 550 gigawatt-hours of energy storage. The government will likely need to approve millions of dollars in funding to upgrade all these facilities — and even more if it retrofits existing nonpowered dams.

According to one report, adding hydropower generation capabilities to nonpowered dams in the United States would cost approximately $2,200 to $34,000 per kilowatt (kW). Potential installed capacity ranges from 200 kW to 70 MW. For most sites, upgrades would cost less than $12,000 per kW. It would take an estimated 20 years to recover the capital invested.

Supporting Gigawatt-Scale Power Generation

Critics will say hydroelectric energy storage systems are geographically limited, as they require water sources and suitable elevation. However, facilities do not need to connect to naturally flowing rivers. Instead, closed-loop systems can pump water between two human-made reservoirs using the same technology.

Despite being established decades ago, pumped storage hydroelectricity is far more efficient and environmentally sound than modern alternatives. In many regions, it continues to be expanded and upgraded. The International Energy Agency believes it will remain the backbone of low-carbon electricity generation. It already provides almost 50% of it worldwide — 55% more than nuclear and more than wind, solar, bioenergy and geothermal combined.

Still, it is often overlooked in favor of chemical battery energy storage systems. By modernizing hydropower, industry leaders will once again establish it as a future-forward solution. While facilities can technically operate efficiently without advanced technologies, digitalization is key for increasing this solution’s marketability and perceived value.

Regardless of where data centers and renewables take electricity demand, the grid must become more reliable and scalable to withstand threats like extreme weather and cyberattacks. The future of hydropower generation lies with flow control infrastructure upgrades.

Pumped Storage Hydropower’s Full Potential

If decision-makers invest in pumped storage hydropower upgrades, America could sustainably add gigawatts of capacity to the power grid in the coming years. Implementation will take time, and it could be years before the country sees a positive return on investment. However, modernization is key, as this technology is critical for the clean energy transition.

Emily Newton is the Editor-in-Chief of Revolutionized, a magazine exploring how innovations change our world. She has over 3 years’ experience writing articles in the industrial and tech sectors.