November 29, 2023
Atlas Copco has supplied a reliable ZBP energy storage system (ESS) to efficiently power cranes at a construction site of a hospital in Alentejo, in southern-central Portugal. ACCIONA, the Spanish multinational company managing the project, has used the battery-based storage system to set up a hybrid solution with a power generator to optimize the environmental footprint of the crane’s electric motor, achieving significant fuel, energy and lifecycle savings. ACCIONA, Atlas Copco’s partner in the region, had been using a diesel-driven generator as the sole source of power for the crane at the construction site of a hospital.
While the unit was able to effectively handle the load profile, and peaks in power demand when the crane was turned on, it became evident that the solution was oversized. Having a variable load profile, with the crane’s high current spikes and low loads, the power generator needed to work 24 hours a day, five days a week, and most of the time out of its optimal operational range. This resulted in excessive fuel consumption, which also impacted costs, additional CO2 and noise emissions, and a higher risk of malfunction and unexpected failure ― since the generator’s engine was operating under very demanding conditions. After several months of using the diesel-driven generator, ACCIONA looked for a more energy-efficient solution to power the crane’s electric motor. The energy storage system benefits from long-life, low maintenance, and high-density Lithium-ion (Li-on) batteries.
When set up in a hybrid solution with a diesel-driven generator, the systems have proven to be ideal for companies operating in low-emission and noise-sensitive applications like metropolitan construction. The ZBP energy storage system is used to cover the low loads, freeing the generator from working in undesirable conditions. As the working day begins and the power demand increases, the generator starts delivering power while the batteries are recharged. When the crane is turned on and power demand peaks, the charged batteries are used to complement the generator’s supply to efficiently power the electric motor.
The 75-kilowatt generator only runs for four hours every two days, when the ZBP needs recharging. As a result, ACCIONA was able to increase its productivity levels onsite while limiting the environmental impact, dramatically reducing daily fuel consumption, CO2 emissions and noise.
