I remember some of the showers at campsites have timers on them, you crank the 5 minute dial to get a quick shower. When you are timed like this you are very conscious of how much longer you have before the water automatically shuts off. I was thinking that I could save tons of hot water fees if I implemented this in my own house although I never did since I would not be very popular with the rest of the family. The next best option would be to monitor shower usage, that is exactly what this DIY Shower Timer Logger does, it uses RFID a RTC and an Arduino to get the job done.

Via: Embedds

“I chose to use an Arduino because it’s my favorite platform and I could program and debug quickly (actually within 5 to 6 hours after starting on the same day). The RFID would detect the proximity of my card (which can be handled with wet hands) and start the timer. When I’m done, I simply wave it again and tell the timer to stop. The duration is then uploade to the website’s API section via the ethernet shield. Yes, I am pretty lucky to have a powerand ethernet port not too far from my bathroom!”