Construction sites require a reliable power supply for tools, lighting, and site facilities. Temporary power is typically provided by diesel generators or by connecting to a nearby grid supply. However, generators have noise and emission issues, and grid connection is not always possible. Energy storage systems, either standalone or in hybrid configurations, are being deployed as an alternative for temporary power. This article covers the practical considerations for using storage on construction sites, with reference to INJET HanCang's equipment.
Construction site loads vary throughout the project lifecycle. During the early stage, loads are low, consisting of lighting and small tools. During the structural phase, loads increase with the use of cranes, welders, and concrete pumps. The load is characterized by high inrush currents from motors. The power system must be able to supply these inrush currents without voltage drops. A battery system with a high C-rate capability can handle these transient loads more effectively than a generator, which may stall or cause undervoltage. INJET HanCang's battery systems are specified based on the peak motor starting current, ensuring stable voltage during motor starts.
Urban construction sites are subject to noise ordinances that limit the permissible sound level during certain hours. Diesel generators produce noise from the engine and exhaust, often exceeding the permitted levels. Battery storage systems operate silently, allowing work to continue during early mornings or late evenings when noise restrictions are strict. The absence of engine noise also improves communication and safety on site. INJET HanCang's storage containers are designed with additional acoustic lining for use in urban areas, but even without it, battery storage is quieter than a generator of comparable capacity.
Construction sites, especially in enclosed or semi-enclosed areas such as tunnels or basements, suffer from poor air quality due to generator emissions. Worker exposure to diesel exhaust is a health concern. Using battery storage for temporary power eliminates local emissions. The storage system is charged off-site or from a grid connection at the site boundary, and the battery provides power without burning fuel on site. This improves air quality and reduces the need for ventilation, which is often required when running generators in confined spaces. INJET HanCang systems are used in tunnel construction and underground parking projects where emission-free operation is required.
When a grid connection is available, the construction site may use a temporary power panel connected to the utility. However, the grid connection may not provide sufficient capacity for peak loads, or the site may be far from the point of connection. A battery system can be installed between the grid connection and the site distribution panel. The battery buffers the grid supply, reducing the peak demand drawn from the grid and allowing the site to use a smaller, less expensive connection. INJET HanCang provides systems with grid-tie functionality, where the battery is charged during off-peak hours and discharged during peak site activity.
Construction sites frequently change layout, so the power system must be relocated to follow the work. Skid-mounted or trailer-mounted systems allow for repositioning as the site progresses. In three-phase systems, imbalances between phases can occur if tools are connected unevenly. The battery inverter can provide phase balancing, drawing power from the strong phase and supplying the weak phase. This reduces the load on the electrical distribution system and prevents overheating of neutral conductors. INJET HanCang's three-phase inverters are configured for this phase-balancing function, improving system stability.
The safety requirements for temporary electrical installations on construction sites are specified in standards such as NFPA 70, which require ground-fault protection and proper grounding. The storage system must include a grounding conductor that connects to the site grounding system. The inverter includes a ground-fault detection function that trips if leakage current is detected. INJET HanCang systems are supplied with a grounding kit and instructions for connection to the site earth electrode. The system's documentation includes the required ground resistance values for proper operation.
The capacity of the battery system is chosen based on the site's load and the duration of the work. For a site that operates for eight hours a day, the battery must supply power for that period if there is no grid connection or generator backup. The sizing process requires a load schedule listing the tools and their duty cycles. The battery capacity is then determined from the total energy consumption over the shift. INJET HanCang offers a sizing service that uses the load schedule to recommend a battery system with adequate capacity, including a margin for temperature-related derating and aging.
In cases where a generator is used, a storage system can be added to reduce the generator's runtime. The generator operates only during the night to recharge the battery, while the battery supplies power during the day when the site is active. This strategy reduces the generator's operating hours and the associated maintenance costs. It also allows the generator to run at a consistent load, which is more fuel-efficient than variable loading. INJET HanCang's control system manages the generator's start/stop schedule based on the battery's state of charge and the load forecast.
Temporary power for construction sites requires reliable, safe, and often quiet solutions. Energy storage systems meet these requirements while eliminating emissions and reducing fuel consumption. INJET HanCang provides storage systems that are portable, easy to install, and sized for the specific needs of construction operations, offering a practical alternative to traditional generator-only setups.