I was recently at the West Coast Green Building exhibition - and saw one product available to recirculate (pump) the water for a sink or shower, until the water was hot to use. Cost about $450.
For $5 - our household uses a bucket in the shower to capture the water - until the water is hot, which is usually around 3 gallons, and then we switch the water to the shower head & proceed. The 5 gallon bucket waits patiently until the next use of the toilet, in which it is poured into the bowl to make the flush.
A simple technique that saves gallons of water - but for most American's it is too inconvenient to:
a) view the bucket in the shower
b) lift the bucket up and pour it into the toilet bowl
So your solution is to invest in the pump that recirculates the water until it is hot enough for one's personal preference.
For the kitchen sink - a $1 plastic tub (holds about 2 gallons of water) is used. When rinsing or washing hands, the water is captured in the tub, and when 1/2 full is taken outside to water the deck plants.
The benefits are:
1) You realize how much water goes down the drain - especially if you are carrying it out to water the plants, and notice the frequency.
2) The plants grow happily with daily attention.
3) The exercise to walk from kitchen to the deck is good for the body...
4) In the conscious action, you make more effort to conserve water.
Neither of the above steps are "fashionable" by American standards, but here's an FYI:
“The average person needs a minimum of 1.3 gallons of water per day to survive in a moderate climate at an average activity level. The minimum amount of water needed for drinking, cooking, bathing, and sanitation is 13 gallons. The average American uses a total of between 65 and 78 gallons of water per day. The average person in the Netherlands uses a total of 27 gallons of water per day. The average person in Somalia uses a total of 2.3 gallons of water per day.” [Source: Water Fact Sheet, Pacific Institute website www.pacinst.org
I've learned this and more through: http://www.longvieweducationassociates.com/