This is a very interesting topic, highly related with the ‘Smart City’. Personally I must admit that I have little idea about which one of my behaviors is the most demanding one in terms of energy. Again, ICT might contribute to help people understanding the consumption patterns. I’m not thinking on sophisticated software which shows you which one of your household goods is the one that demand more energy. Maybe a simple mobile solution, let’s say an android software in your mobile, connected with the electricity provider which shows (graphically) your current consumption might help. Having this people will be aware how much their consumption increases when, for example they use the washing machine.
I found the mobile app idea very interesting so dug a round a little.
I found an interesting, but old article (2009), which suggested only 13 percent of people say they would want to manage home energy consumption via a mobile device (http://gigaom.com/2009/08/04/7-iphone-apps-to-manage-energy-consumption)
A more recent article (March 2013, http://bit.ly/15PYzpp) provided an overview of the 'top ten' energy efficiency apps. Several suggest the sort of approach you advocate. But most require a good deal or preparatory work to better understand energy consumption from individual devices. We seem to be part of the way 'there'.
Energy Performance Certificates are common in many parts of Europe. They provide an overview of how energy efficient a property is. I’ve seen them in many larger public buildings. In the US Energy Star labels have been shown to attract rental premiums and sale price premiums for more energy efficient buildings
I believe they were introduced in Spain for residential property on 1 June 2013. This might provide a basis for comparison. But I doubt this topic of conversation will arise spontaneously between neighbors.