What storage actually solves
Solar makes electricity only while the sun is up. The hours when electricity is most expensive and most needed are often after it sets. Storage closes that gap.
It holds the surplus from the middle of the day to use or sell in the evening, cuts consumption in the expensive hours, and supplies power when the market calls for it, for a payment.
As renewables grow, the grid becomes less stable and curtailment rises. Nationwide curtailment was 169,812 MWh in 2025, and 164,012 MWh in the first half of 2026 alone. The value of somewhere to put generation instead of throwing it away rises with it.
Source: Korea Power Exchange data submitted to the office of Assembly Member KIM Wi-sang, reported by Maeil Shinmun on 2026-08-04
Three purposes, three designs
| Purpose | What it does | Who it suits | What decides it |
|---|---|---|---|
| Paired with solar | Stores generation and shifts it to a different hour to sell, or raises the self-consumption rate | Generators, and sites that consume their own output | The balance between the generation profile and the storage capacity, and what the rules recognize |
| Peak shaving | Lowers consumption in the peak demand hours, cutting both the capacity charge and the energy charge | Factories and buildings with high contracted capacity and a pronounced peak | Load pattern analysis, the effect of adjusting contracted capacity, and the payback period |
| Market participation | Offers capacity to the power market and to ancillary services for payment | Operators above a certain size, and VPP participants | Eligibility requirements, metering and communications equipment, and how settlement works |
Swipe the table sideways to see the rest
Safety weighs as much as economics
Storage means handling batteries. Fire safety standards, siting requirements, fire protection equipment, and a monitoring regime for operation all have to be in the design from the start. Retrofitting them costs far more.
Indoor installation and outdoor container systems carry different requirements, and the building use and the separation conditions determine which is available. We also look at how the battery management system (BMS), the power conversion system (PCS), and the supervisory platform are designed to work together.
Insurance terms are checked in advance too. Underwriting conditions and rates move with the installation method and the level of safety equipment, so it is better to build the insurer's requirements into the design.
How we approach it
The first thing we settle is why storage is needed at all. Fixing the capacity before the purpose is the quickest route to over-investment.
Then we calculate with real data. We put in the generation profile, the load pattern, and the tariff, vary the storage capacity, and find the point where the payback period is shortest. If it does not pay, we say so.
Once the design is fixed we compare and select partner EPCs and products, and for the operating phase we set the charge and discharge strategy alongside a plan for managing degradation.