Energy storage technology enables electricity to be stored and dispatched when it is most valuable—improving power reliability, supporting renewable energy, and stabilizing energy costs for commercial businesses. For organizations evaluating battery energy storage systems (BESS), the technology is most effective when deployed as part of a broader on-site energy strategy, such as e2Companies’ Virtual Utility®.
Energy storage systems play a critical role in balancing electricity supply and demand, particularly as solar power and wind power introduce variability into the energy grid. According to the International Energy Agency, grid-scale energy storage capacity must expand significantly this decade to support global renewable energy targets.
What is energy storage technology?
Energy storage technology refers to systems that store energy produced at one time for use at another, allowing electricity generation and consumption to be decoupled. These systems store energy in various forms, including chemical, mechanical, thermal, or electrical, and release it when needed to support the electric power supply, manage peak demand, or provide emergency backup power.
For commercial and industrial users, energy storage is no longer just a grid-scale concern. On-site energy storage systems now play a direct role in:
- Managing electricity demand charges
- Improving power quality
- Supporting renewable energy integration
- Maintaining operations during grid outages
Types of energy storage technologies
There are multiple types of energy storage, each suited to different use cases based on power capacity, storage capacity, response time, and duration.
Mechanical energy storage
Mechanical storage systems store energy through physical movement or pressure. Examples of this include:
- Pumped hydroelectric storage (pumped storage hydropower)
Uses off-peak electricity to pump water uphill, releasing energy when water flows back downhill through turbines. Pumped hydro represents the largest share of global electricity storage capacity but is limited by geography. https://www.energy.gov/eere/water/pumped-storage-hydropower
- Compressed air energy storage (CAES)
Stores energy by compressing air in underground caverns and releasing it to generate electricity. CAES is suitable for long-duration storage but requires specific geological conditions.
- Flywheel energy storage systems
Store kinetic energy in a rotating mass. Flywheels provide high power and fast response but relatively low energy capacity, making them useful for power quality applications rather than long-duration storage.
Thermal energy storage (TES)
Thermal energy storage systems store heat or cold for later use.
- Molten salt used in concentrating solar power
- Ice storage for cooling demand management
- Solar thermal energy systems that shift heat production to off-peak hours
TES is commonly applied in district energy systems and large commercial buildings to reduce peak electricity demand.
Electrochemical energy storage (battery storage)
Battery energy storage systems are the most widely deployed solution for commercial energy storage.
- Lithium-ion batteries dominate the market due to high energy density, efficiency, and declining costs
- Lead-acid batteries remain in limited use but have lower cycle life and energy density
- Flow batteries offer longer duration but higher upfront costs
Battery storage converts electrical energy into chemical energy and back again, allowing systems to store electricity from solar power or off-peak grid electricity and release energy when needed.
Battery energy storage systems for commercial businesses
For commercial applications, battery energy storage provides flexibility that traditional generation cannot. When paired with solar and wind power, BESS allows surplus energy to be captured instead of curtailed and dispatched strategically.
According to the U.S. Department of Energy, battery storage can reduce peak demand, improve grid resilience, and support renewable energy integration. https://www.energy.gov/oe/energy-storage
How e2Companies applies battery storage differently
e2Companies does not deploy battery storage as a standalone asset. Instead, storage is integrated into the R3Di® System, a utility-grade on-site energy platform that combines:
- Battery energy storage
- On-site generation
- Intelligent power controls
This architecture allows commercial facilities to:
- Maintain stable power flow during grid disturbances
- Dispatch stored energy to support critical loads
- Improve power quality across the electrical system
- Scale storage capacity as operational needs grow
In many consulting and deployment engagements, planning begins with a 1-megawatt R3Di® configuration, which can supply high power capacity for entire facilities—not just limited backup circuits.
Energy storage and renewable energy integration
Energy storage is essential for integrating renewable energy sources into the electricity grid. Solar and wind power generate electricity intermittently, often producing excess electricity during low-demand periods.
Energy storage systems allow commercial facilities to:
- Capture surplus energy during off-peak hours, including excess solar generation or lower-cost grid electricity
- Release stored energy during peak demand, reducing demand charges and exposure to volatile utility pricing
- Reduce reliance on utilities and fossil fuels by supplying on-site power when grid conditions are constrained
- Improve grid electricity stability and power quality by smoothing fluctuations and responding instantly to disturbances
e2Companies extends these capabilities through its Virtual Utility®, which treats on-site generation and battery storage as an integrated power system rather than isolated assets. Under this approach, energy storage is continuously coordinated with facility load, utility rates, and grid conditions, allowing power to be stored and dispatched strategically. It can also instantaneously pick up a facility's full load in the event of an outage.
At the core of this model is the R3Di® System, a utility-grade platform that combines battery energy storage, on-site generation, and intelligent controls. The R3Di® System enables commercial facilities to store energy when it is least expensive or most abundant and dispatch it when it provides the greatest operational or financial benefit, whether that is reducing peak demand, supporting critical loads, or maintaining operations. The system is a self-contained, stackable unit supplying 1 megawatt of power, making it easily scalable as a facility's power needs increase.
It can also integrate easily with renewable sources, such as wind and solar power, making those resources more reliable.
This allows companies to solve reliability challenges and achieve ESG goals without compromising operations.
Emergency backup power and power quality
Many commercial and industrial facilities rely on diesel or natural gas generators for emergency backup power, but generators alone are designed primarily for extended outages, not for the power-quality events that occur far more frequently on today’s grid. Voltage sags, momentary outages, frequency deviations, and other short-duration disturbances can disrupt operations, damage sensitive equipment, and trigger costly downtime—often without ever activating a generator.
Battery energy storage systems respond instantly, delivering power in milliseconds to support power quality and bridge the gap between grid failure and generator start-up. This instantaneous response stabilizes voltage and frequency, protects sensitive loads, and enables seamless transitions during outages without interruption to operations.
When battery storage is integrated with on-site generation, facilities gain true resilience and the opportunity to not only reduce costs, but increase revenue by strategically curtailing power to earn utility rate incentives.
e2Companies applies this approach through its Virtual Utility® and R3Di® System, which are engineered to deliver utility-grade power at the facility level. Rather than protecting only select circuits, the system is designed to support entire facilities with high power capacity and intelligent controls that maintain stability across changing grid conditions.
For mission-critical organizations, this reduces operational risk by minimizing unplanned downtime, protecting equipment performance, and ensuring continuity even during extended grid disruptions.
It also gives them greater energy choice and the ability to reduce their reliance on the public utilities.
If your organization is evaluating how to improve reliability and resiliency while optimizing costs and investing in more sustainable solutions, schedule a discovery call with us.
Our team will review your facility’s power profile, generation assets and potential tax credits and savings to identify where on-site generation and energy storage could provide the greatest operational and financial value.
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