pypsa-eur/data/retro/window_assumptions.csv

1	strength	u_value	cost	u_limit	comment
2	[m]	[W/m^2K]	EUR/m^2	[W/m^2K]
3	0.076	1.34	180.08	3.5	Double-glazing
4	0.197	0.8	225	1.3	Triple-glazing
5
6	source: https://www.agora-energiewende.de/en/publications/building-sector-efficiency-a-crucial-component-of-the-energy-transition/ p.115