This one starts with a scenario that feels almost comically unfair once you see it clearly: you're a landlord with a broken heating system, but your tenants pay the bills. You're a tenant in a freezing apartment, but you don't own the building. So neither of you does anything — and the cold just... continues. That's the split incentive, and Nicholas lays out just how structurally maddening it is: in the US alone it wastes between $4 and $11 billion a year, and renters use 2.7% more energy overall than homeowners simply because landlords haven't invested in efficiency.

It gets worse. Even when landlords could charge higher rent for an efficient building, tenants in Berlin studies only valued each euro of energy savings at 23 cents more in rent. A balcony? Worth more than insulation. Partly because Energy Performance Certifi ...