I think it is clear that it is about using more energy-efficient technologies. I think your challenge is well narrowed down, it is about technology and how to make people use the new technologies, and not how to change peoples behaviours when using electricity for example. Something I find interesting is if you could change old technology into becoming more efficient and so on, without having to replace the whole thing.
Interesting challenge area. Linnea also makes an interesting point about retrofitting/updating old technology, as well as installing new technology. Marina - perhaps you can work this additional angle somehow into your challenge, so it's not narrowed only to installing new technology?
Hello Marina, I have framed a similar challenge to yours but I am focusing on the Industries.
Governments are coming up with laws instead leaving it to the choice of owners. Germany and the Europe Union have come up with regulations for Energy efficiency of Buildings. Buildings are to be certified based on performance and there is even a finance mechanism for supporting this transition.
EU targets that all new Buildings by 2020 has to be zero energy buildings (Green building). Retrofit is the way for existing buildings.