A novel energy storage solution designed for skyscrapers has been developed by researchers at the University of Waterloo in Canada. This innovation, a solid gravity energy storage system, is aimed at efficiently storing renewable energy by integrating photovoltaic panels, small wind turbines, and traditional lithium-ion batteries. The design optimizes energy use in buildings while reducing dependence on the grid, which may significantly advance sustainable practices in urban architecture.
The gravity energy storage system utilizes a unique combination of components, including a motor-generator unit, hoisting ropes, gears, and a substantial weight typically made from steel or concrete. The system functions by harnessing energy produced by the building’s faŅ«ade-mounted solar panels and wind turbines. During the energy surplus phase, the motor lifts a heavy mass to store gravitational potential energy. This energy is then converted back to electricity by the generator when energy demand exceeds supply.
Researchers found that the system has achieved competitive levelized cost of electricity (LCOE) values ranging from 0.051 to 0.111 USD/kWh, along with grid dependency (GD) values between 0.195 and 0.888, depending on the specific building design. Interestingly, taller structures with larger floor areas tend to demonstrate lower LCOE but higher GD, underscoring how building characteristics can influence energy efficiency.
Moreover, the study indicated that the gravity storage component is vital for enhancing system autonomy, capable of meeting up to 100% of average daily demands for various building styles. The researchers emphasized the importance of further investigation into factors like demand variability and climate impacts. They suggested exploring the feasibility of shared gravity storage systems across multiple buildings and perform comprehensive life-cycle assessments to understand the full potential and limitations of this technology in different environmental conditions.