Operational Analysis of Distributed Energy Storage Systems for Commercial & Industrial Behind-the-Meter Applications

Energy storage technology, a focal point in new energy, stores electricity for grid peak/valley supply adjustment. Distributed energy storage in commercial/industrial contexts cuts costs via peak - shaving, boosts grid stability, and mitigates peak - valley imbalances. This paper explores its application for commercial/industrial users from scenarios and feasibility.

1 Application Scenario Analysis
1.1 Demand Analysis

Electricity costs dominate commercial/industrial energy expenses, especially for manufacturers—10% - 20% of total costs for general firms, up to 40% - 50% for smelters. Distributed storage enables peak - shaving, self - supply, and demand - side response, optimizing energy structures, slashing consumption, and enhancing competitiveness.

1.1.1 Peak - shaving & Valley - filling

Based on user consumption patterns and local tariffs, deploy appropriately sized storage. Charge during low - cost valley/flat periods, discharge at high - cost peaks to reduce peak loads, avoid premium power purchases, and lower electricity costs.

1.1.2 Self - Supply

Economic growth drives urban electricity demand, creating seasonal/periodic shortages. To ensure grid stability during supply crunches or emergencies, utilities use orderly power schemes, incentivizing firms to cut peak - load demand or boost valley - period consumption.

1.1.3 Demand - Side Response (DSR)

DSR, a key solution for power supply - demand tensions, describes users proactively adjusting electricity loads under incentives. It enables peak - shaving/valley - filling. With distributed storage advancements, DSR pilots are expanding. Provincial utilities now issue incentive schemes, cementing energy storage’s market status.

1.2 Load Analysis

Commercial/industrial distributed storage suits diverse scenarios and load types: day - shift, three - shift production, and random - fluctuation loads.

1.2.1 Day - Shift Load

The load curve is smooth: rising to a stable peak post - workstart, then falling to a valley after work. For example, a mall ramps up at 8:00 am, peaks at 9:00 am–6:00 pm (stable, low fluctuations), drops post - 6:00 pm, and hits a valley 10:00 pm–8:00 am.
Typical users: commercial complexes, offices, day - shift manufacturers. Peaks align with daytime high tariffs, valleys with nighttime low tariffs—ideal for peak - shaving.

1.2.2 Three - Shift Production Load

A 24/7 continuous load with minor fluctuations (e.g., during equipment ops/material changes). Common in mining/metallurgy, using 24h gear (ventilators, compressors). Production - focused firms face high costs and strict reliability needs, suiting storage for peak - shaving, self - supply, etc.
Billing: two - part industrial (basic + energy charges). Storage design must account for charge - discharge impacts on basic fees.

2.1.1 Low - Voltage Connection (Continued)

The low - voltage connection method features advantages like a simple connection scheme, low retrofit costs, and straightforward procedures. However, it imposes relatively high requirements on the transformer load rate and load absorption capacity. Moreover, it only works for the load of the specific transformer and cannot supply power to loads of other transformers.

2.1.2 High - Voltage Connection

High - voltage connection means the energy storage system, via its built - in step - up system, connects to the user’s 10kV bus at the 10kV voltage level. It suits scenarios where the user’s existing transformer has no extra capacity for energy storage charging, or where there are multiple user transformers with uneven load distribution. The specific wiring method is shown in Figure 2.

This method advantages: energy storage charging unaffected by transformer load rate, unrestricted charging power, simultaneous load absorption for multiple transformers, and high absorption rate. Disadvantages: higher energy storage system costs; need for high - voltage retrofits of users' power systems (adding retrofit costs); and longer, more stringent process for business expansion/capacity increase at grid companies.

2.2 Charging & Discharging Strategies

Connection methods determine initial energy storage construction costs; charging/discharging strategies dictate revenue.Strategies vary by scenario: e.g., self - supply mode discharges during grid curtailment/shortages; demand - side response follows power department policies. Peak - shaving/valley - filling, the key commercial/industrial use case, requires strategy design based on time - of - use tariff periods and prices.

2.2.1 Time - of - Use Tariffs

Take a province’s 110kV large - industrial tariffs as an example; details in Table 1.

2.2.2 Analysis of Charging and Discharging Strategies

By analyzing the time - of - use electricity prices, there is one valley period, two flat periods, and two peak periods each day. For the energy storage system, adopting a strategy of charging twice and discharging twice a day yields the best economic efficiency, involving one peak - valley cycle and one peak - flat cycle.

3 Conclusion

The application of distributed energy storage technology in the commercial and industrial field helps improve the stability and safety of the power grid, can alleviate the problem of power peak - valley differences, and at the same time, can provide more reliable power supply for users. The commercial and industrial user side is a typical application scenario for distributed energy storage. On the basis of saving electricity costs and bringing benefits to users, it can also effectively improve the consumption rate of clean energy, effectively reduce electricity transmission losses, and contribute to the realization of the “dual - carbon” goals.

The energy storage system can realize power regulation on the load side through battery charging and discharging strategies, save electricity charges by arbitraging the peak - valley price difference, and can further expand benefits by cooperating with demand - side response, capacity management, etc.