Sometimes saving the environment seems like an exercise in denial: don't buy things, don't take planes, don't use your car. Now personally, I think saving the world might be worth a teensy sacrifice, but it is lovely when saving resources also adds a little more comfort to your life. How long before you want to step into a steaming hot shower do you turn the water on? One minute, three minutes, perhaps even five minutes? Well, if I can assume you have a low flow shower head, which would be max of 2.5 gallons per minute, you might be wasting as much as 15 gallons of water per shower. What is that you say, you did not like the low flow shower head you tried, and so you replaced it? Oh no.... you are wasting even more while you wait for the hot water.
Well first of all, please get a low flow shower head back into your shower. The new ones are very nice, are under 1.6 gpm, and have great pressure.
I also used to waste a lot of water, (although I never removed the low flow head) because my hot water tank was in the basement. I have molto, molto, good vibe hot water from my fabulous solar hot water panels on my roof, but it took a LONG time to get to me! I had thought about using a tankless hot water as the back up to my solar system (we currently use the old gas heater as the back up for cloudy days), and placing it next to my bathroom, but have you priced a tankless water heater lately?
My problems were solved when I went to a plumbing presentation at last year's West Coast Green. It introduced a product that is a demand circulation pump for hot water. Basically, when you want hot water, you want it right NOW. This little item is a small pump that fits under your sink, and is actuated by a pushbutton. A few minutes before you want your shower, you push the button. The pump starts sucking hot up towards your bathroom through the hot water line, and returning it to the tank through the cold water line. When hot water is up at your bathroom, a thermostat turns the pump off. This not only saves water, it also makes your life more pleasant. No more stepping into a luke warm shower, because you did not wait long enough.
My clever husband installed it, and it was finished in an afternoon. I got a D-mand system, but there are others out there.
Demand recirculating system --------- $300
Hot water when and where I want it---- Priceless