Buildings use a high percentage of global energy, especially in developed countries. Every unit of energy that can be saved can be one less unit of energy from fossil fuels.

So how can developed countries make their buildings more energy efficient?

One way is the road of international agreements which are then implemented through national regulations. But we know this road is closed at the moment.

Another way is bottom up, block by block, neighbourhood by neighbourhood, community by community.

Imagine if every building for visitors had its energy rating on the door. Just like we do with fridges and vacuum cleaners, from A+ down to G. A sheet of paper in the window is something everyone can do.

The group of buildings for visitors should include blocks of apartments for rent as well as shops, schools, colleges, places of worship, community centres, and official buildings.

The social pressures across villages, towns, cities and countries to increase the energy efficiency of our buildings would be catalysed, making the world a better place because it could reduce global carbon emissions starting from now.

It might even help unblock the road to international agreements on climate breakdown.

Every street can help the world.