Requirements

Photovoltaics in Apartment Buildings for Common-Area Power. For a modern apartment building (30 residential units) with two elevators, a sustainable energy solution was needed to cover the common-area electricity consumption. The goal was to reduce energy costs and support the energy transition using a photovoltaic system for apartment buildings combined with a battery storage unit in the basement. A tenant power model was considered initially but ultimately ruled out due to the limited available roof space. The cost-benefit ratio did not justify the investment. Instead, the focus was placed on a conventional PV system designed to cover as much of the common-area electricity through photovoltaics as possible—particularly for elevators, lighting, and building systems.

Technical Implementation

The technical implementation of the PV system for the apartment building included both the flat roof and an additional pitched roof to maximize usable space, making it possible to install photovoltaics despite limited roof area. On the flat roof, Solmont mounting feet were used to minimize ballast while ensuring a secure installation—ideal for larger buildings with structural limitations. High-efficiency 450 Wp PV modules were installed to ensure the most efficient use of available roof space—a critical factor in PV systems for multifamily buildings with space constraints.

Cabling was routed through an old, unused exhaust shaft down to the basement, a cost-effective and technically simple solution. In the basement, two inverters and a battery storage unit were installed directly next to the meter distribution system. This setup allows for intelligent and demand-based distribution of the generated solar power. Thanks to the combination of the PV system and storage, the common-area electricity consumption in the apartment building is now largely covered by renewable energy. This solution is especially suitable for property managers and homeowners' associations looking for a cost-effective and practical energy supply—without a tenant power model, but with a long-term sustainable impact.