It would be very interesting, but I don't know how you'd measure it. A quick search yielded this http://www.squidoo.com/water-meter. Some interesting reading.I think it would be interesting to monitor the amount of water used. I could keep a graph on consumption / temperature / time. It would for sure reveal the differences between summer and winter months. I'll just need a small water meter that can measure a trickle and install it in the supply line inside the humi. The supply starts here and goes through the wall and up to the humidifier.