In our market, Finland, industry use seems to dictate energy cost which leads to high costs during the day and low cost during the night. The lowest cost timeslot is not at the same time every night, and here OpenHAB comes in handy, it finds the cheapest consecutive cost every day, automatically = smart home.
Because I am an engineer and love tinkering with technology. Like adding WIFI to a washing machine that had none. The relays cost 5€. The washing machine uses about 230 kWh a year. If I can save 5c/kWh by running the machine by night I will have paid back the relays in half a year. I guess total saved money equals a Pizza and a beer per year. So I am not doing it for the money but for the love of technology.
I love OpenHAB because it suits my needs so well. But I am an outlier, the mass market will never do what I did. Productification, productification, productification!