When The Sun Sets & The Wind Stops: Powering Through with Storage & Flexibility
To integrate renewables at scale, the grid must store energy when it’s plentiful and discharge it when it’s scarce. Long-duration storage provides critical backup during extended periods of low supply. Distributed energy resources bring flexible, localized power closer to demand. Vehicle-to-grid systems unlock the storage potential of EV fleets, enabling them to feed electricity back to the grid. Virtual power plants tie it all together—coordinating these distributed assets through software to balance supply and demand and deliver reliable, system-wide performance.
Cheap, renewable power isn’t available on demand. The sun sets, the wind calms, seasonal drought rears its ugly head — but our need for electricity never stops. Of course, every power source has limits; the difference is that renewables’ constraints are predictable and ever-present. The answer? Store energy when it’s plentiful and shift demand when it’s not. Energy storage banks excess power for later use, while demand flexibility moves energy-hungry activities — like charging EVs or running industrial equipment — to times when renewables are abundant. Innovation to expand storage and make power plants, consumers, and businesses more responsive to grid needs could unlock the full potential of renewables — allowing our grid to provide the reliable, affordable, round-the-clock clean energy we need.
Using IPCC and GCAM data, Energy Innovation projected future “greenhouse gas emissions at stake” in 2050, assuming current policies remain in place. The resulting estimates overlap because different technologies may reduce the same emissions pool.
The Path We're On
When supply and demand are out of sync
The clean energy transition will be powered by abundant and low-cost renewables like solar and wind. The catch: to unlock their full potential, we need an electricity ecosystem that is as adaptive and flexible as these new energy sources are powerful. Traditional grid infrastructure, markets, and customer rates designed for the constant output of fossil fuel plants responding to static customer demand, need to be retooled to ensure there’s plentiful energy on sunny days, on windy days — and on days that are neither.
That’s where energy storage and demand flexibility come in.
Energy storage and demand flexibility help balance the grid.
Both help balance a power system dominated by variable renewables — but they do so in different, complementary ways.
Energy storage shifts electricity across time. Batteries, pumped hydro, thermal storage, and other technologies capture excess power when it’s abundant — for example, midday solar or overnight wind — and release it later when supply tightens. Battery storage is especially valuable for covering short gaps, smoothing ramps, and maintaining reliability when renewable output drops suddenly.
Demand flexibility shifts when electricity is used. Instead of forcing the grid to meet rigid demand at all times, flexible loads — such as EV charging, heating and cooling, data centers, or industrial processes — can move energy-intensive activity to periods when clean power is plentiful and cheap. By reducing peaks and filling valleys, demand flexibility lowers strain on the system altogether.
In a clean power system, the goal isn’t to eliminate variability — it’s to manage it intelligently. Today, flexible fossil plants often fill the gaps when wind and solar dip. Energy storage and demand flexibility make it possible to cover those gaps with clean, low-cost flexibility instead — keeping power reliable and affordable, while also cutting reliance on fossil backup. Scaling these technologies is key to building a resilient grid that can run with enormous amounts of renewable energy.
Storage and demand flexibility are two of the main ways the electricity system adapts to the variability of wind and solar — but they don’t work on their own. As electricity demand grows and clean generation scales rapidly, the system must also integrate and transport this larger volume of low-emissions power. Transmission helps manage the increased load by allowing power to flow from areas with surplus generation to those facing shortfalls, reducing the amount of storage needed in any single location and enabling clean power to be deployed where it’s most cost-effective. Clean peaker plants — low-carbon resources built to run only during peak demand — add another layer of flexibility.
When these resources work in tandem, they can complement one another in important ways — sharing reserves, lowering overall costs, and reducing the need to overbuild generation, storage, or transmission infrastructure. This kind of coordination is essential for running a reliable, affordable grid with high levels of renewable energy.
A New Way Forward
Building a Smart and Flexible Grid
To move from a rigid, fossil-era grid to one that’s intelligent, responsive, and clean, we need innovation that ties generation and consumption together in real time. The next frontier isn’t just adding more renewables — it’s creating the connective tissue that lets the grid sense, respond, and balance itself across millions of devices and users. Tools such as virtual power plants (VPPs) and distributed energy resource (DER) management systems can aggregate and coordinate batteries, EVs, appliances, and other distributed assets — turning thousands of small resources into grid-scale flexibility. The following imperatives chart a path toward that vision: a grid that dynamically aligns supply and demand, stores clean energy across all timescales, and transforms electricity into the most flexible and reliable resource in the clean energy era.
Innovation Imperatives
Create technologies to help orchestrate a grid that can align supply and demand across all sectors
To build a truly intelligent grid, we must flip the traditional energy model from a one-way street to a dynamic conversation between supply and demand. This imperative is focused on creating the orchestration layer — software, sensors, and communication networks — that shifts energy-intensive tasks so they happen at times when power is plentiful. Tools that enable this coordination include virtual power plants (VPPs), distributed energy resource (DER) management systems, and digital twins that model and optimize grid behavior. With this orchestration layer in place, industrial plants, data centers, commercial buildings, and household appliances can automatically shift their high-energy tasks to times when clean energy is abundant and cheap. This approach smooths out the grid’s peaks and valleys, dramatically increasing efficiency and reducing the need to overbuild capacity to meet peak demand.
Integrate abundant distributed, grid-responsive short-term energy storage for residential, commercial, and industrial applications
Instead of relying solely on large, centralized energy storage facilities, this imperative aims to build a resilient energy backbone by embedding storage throughout the grid's endpoints. The idea is to create a vast, aggregated network of batteries — whether in buildings or grid-connected electric vehicles — that can collectively absorb surplus renewable energy when it's abundant, then dispatch it locally during periods of high demand. Innovating the systems to integrate these distributed assets transforms millions of passive consumers into active participants, enhancing grid stability and building a more modern, flexible electricity system from the ground up.
Develop energy storage lasting from days to entire seasons to provide dispatchable, around-the-clock clean electricity
While we already have several pathways for long-duration storage, such as pumped hydropower, significant economic and technical barriers prevent them from scaling to meet global grid demand. The core innovation challenge is developing new storage media, systems, and chemistries that drastically reduce capital costs, are location-agnostic, improve round-trip efficiency, and minimize energy leakage over multi-day to seasonal timelines. Achieving this will enable the affordable storage of vast amounts of renewable energy and make a reliable, 100% clean grid a reality.
Moonshots
Your Moonshot Here: Help chart the road ahead by contributing to the Climate Tech Map
Our expert contributors haven’t yet identified a moonshot for this opportunity area, and we want your ideas. Moonshots are high-risk, high-reward approaches that could dramatically outperform today’s leading solutions, even if they remain technologically unproven or commercially far-off today. They aim for step-change impact, not incremental gains. If you see a scientifically plausible concept that could redefine what’s possible in this space, we invite you to submit it for review. Send your game-changing idea to ideas@climatetechmap.com.
The most viable solutions will:
Storage and demand flexibility solutions only scale when the governments, utilities, businesses, and customers expected to adopt them have a clear financial reason for doing so. The most viable approaches make their value easy to capture — through lower energy bills; avoided capital costs; or revenue from energy, capacity, or ancillary service markets — rather than relying on unrewarded behavior change or diffuse system-wide benefits.
Because storage and flexibility can reduce the need for new generation, transmission, and peaking capacity, their value is best measured at the system level. The most viable solutions lower total system costs by reducing peak demand, deferring infrastructure investment, or improving asset utilization — not just by minimizing the cost of an individual device or project.
Storage and demand flexibility must work within today’s grid architectures, planning processes, and operational practices. Solutions that can be layered onto existing systems, aggregated across many assets, and coordinated within the practical limits of real-world grid operations and markets will scale faster and more reliably.
A clean, reliable power system requires flexibility across minutes, hours, days, and longer periods of low renewable output. Promising solutions deliver flexibility that aligns with real operational needs — whether through fast response, sustained discharge, or predictable load shifting — and complement variable wind and solar generation.
Storage, demand flexibility, and transmission perform overlapping roles in balancing a renewable-heavy system. The most valuable solutions recognize this interplay and integrate planning across generation, transmission, storage, and demand. Doing so helps smooth variability across time and space, share reserves, and reduce the need to overbuild generation, storage, or network infrastructure.
