Construction sites – Mobile power supply on construction sites and at events without mains power

Construction projects often require high power for machines, tools, cranes, lighting, etc. At the same time, consumption is not constant: there are peaks during the day (e.g., when several devices are running at the same time), while demand drops sharply at night or during breaks. However, a conventional generator would have to run even at low loads—inefficiently and with increased wear and tear. This is where hybrid solutions come into their own:

• Power reserves: The hybrid system uses the battery inverter to provide high currents at short notice to cover the starting currents of motors or welding equipment. This allows a smaller diesel to be used, which does not have to be dimensioned for peak loads. The battery acts as a buffer and supplies the peak current, while the generator only has to carry the average load.
• Demand-based operation: The diesel generator only runs when really necessary – i.e., to charge the battery or when the load exceeds the battery capacity. When consumption is low (e.g., lighting at night, office containers), the generator switches off completely and the battery alone supplies the construction site. The result: significantly less frequent engine operation, which saves fuel and extends the service life of the unit.

A hybrid generator can also serve as a security hub on construction sites: some systems integrate cameras, motion detectors, and alarm systems directly into the generator trailer. Since a continuous power supply is available anyway, it makes sense to equip the construction site with video surveillance and lighting—burglary attempts can be detected and reported, and sirens and spotlights deter thieves. The power supply thus also acts as a security service, which can prevent theft in 90% of cases.

Emergency systems (e.g., pump sump drainage, fire alarms) can also be connected to the battery so that they are active at all times, regardless of whether the generator is running. This increases safety on the construction site and, in case of doubt, can prevent damage even if the generator is turned off at night.

• Massive fuel savings: Optimized operation reduces diesel consumption by 50–80%, depending on the load profile. This saves enormous operating costs. Less refueling also means less logistical effort (less frequent diesel refills).
• Less noise and exhaust fumes: Since the generator remains off most of the time or runs in an efficient load range, noise pollution is significantly reduced. Construction sites are often located near residential areas where noise regulations apply – a hybrid generator enables whisper-quiet operation over long distances. Exhaust emissions are also reduced in proportion to the lower fuel consumption. For workers on site, this means a more pleasant, healthier working environment, and for the environment, fewer pollutants.
• Stable voltage, better quality: The battery inverters deliver clean, stable voltage and can quickly compensate for load fluctuations. Unlike small generator sets, which can experience voltage drops during load changes, the hybrid system maintains a stable voltage supply – important for electronics or precision machines, for example.
• Device and machine protection: The system avoids the harmful effects of generator operation at idle or under load, which can cause engines to become clogged with soot and damage machines. In addition, the diesel always operates in the optimal range, which extends maintenance intervals (up to 80% fewer service calls have been reported).
• Easy mobility: The hybrid power supply can be provided in the form of a container or trailer system. Many suppliers (e.g., MobilHybrid) build the technology into 10-foot containers or trailers that can be easily delivered to the construction site and removed again at the end of the project. The setup is plug-and-play—just connect and get started—and the unit can be moved to another location if necessary.
• Optional PV integration: Some construction site hybrid generators allow the connection of mobile solar modules. This allows solar energy to charge the battery directly during the day, further reducing the load on the diesel generator. This makes particular sense on longer-term construction sites or in temporary facilities (construction site offices, container villages), where a few kW of solar panels on the roofs quickly pay for themselves.

Construction sites often have high starting currents—e.g., cranes, concrete mixers, or welding equipment, which draw a lot of power for short periods of time. In the past, oversized generators had to be provided for this purpose. A hybrid system with a powerful inverter (e.g., 3-phase with 10 kVA modules) and battery storage buffers these peaks. This means that a comparatively smaller generator plus battery can do the same work as a much larger diesel generator alone. This significantly reduces costs and fuel consumption.