As a visible sign of the shift from fossil fuels to renewable energies, a former coal silo and heating plant in Basel is covered with coloured PV modules. The entire site is under heritage protection, the remodelled building was required to match the style and colour scheme of the site.

In terms of walls, the building envelope was thermally insulated. The northern and southern facade (as well as the roof) are equipped with BIPV, the east and west facades are plastered. An outside stair and lift tower are located on the north side.

• U-value (pre-intervention) [W/m2K]: 2,0W/m²K
• U-value (post-intervention) [W/m2K]: 0,16W/m²K

The mostly windowless massive concrete walls do not allow for traditional uses without major structural changes. There were few windows before the remodelling. The existing windows were replaced:

• Existing window U-value Glass [W/m2K]: 3,5
• New window U-value Glass[W/m2K]: 0,7
• Existing window U-value Frame [W/m2K]: 3,0
• New window U-value Frame [W/m2K]: 1,4

The roof has been completely remodelled. Only the structural beams remained from the old construction.