Showers are also a source of lost energy... flushing all that hot water out of the house. From a few years ago: https://www.washingtonpost.com/news/energy-envir

Showers are also a source of lost energy... flushing all that hot water out of the house. From a few years ago: https://www.washingtonpost.com/news/energy-environment/wp/2015/03/04/your-shower-is-wasting-huge-amounts-of-energy-and-water-heres-what-to-do-about-it/ https://www.washingtonpost.com/news/energy-environment/wp/20... This gets into drain water heat recovery https://www.energy.gov/energysaver/drain-water-heat-recovery https://www.energy.gov/energysaver/drain-water-heat-recovery https://www.kitchenandbathclassics.com/eco-friendly/advanced-plumbing/drain-water-recovery/ https://www.kitchenandbathclassics.com/eco-friendly/advanced...