If you own the apartment, you can formally present to the building board that solar panels should be built on the roof. They would be owned by you, some group o

If you own the apartment, you can formally present to the building board that solar panels should be built on the roof. They would be owned by you, some group of people living there or the housing association. If you're a tenant looking for an apartment you can keep asking it from landlords. Hopefully they start seeing that it's something that can be a distinct factor. If you're a company doing real estate software, you can incorporate info about solar panels (and things like energy efficiency metrics) to the software.