Here are three areas where significant energy might be saved in a home with fairly simple systems. One has to do with using some of the heat in the hot air up in your attic, and the other two have to do with recovering some of the heat we waste in showering.
Regular showers are a major waste of energy. Typically we spend about 3 KWH heating water for a shower, and then send about 85% of that energy right down the drain. It amounts to about 300 KWH for a family of 4 per month.
Using The Heat In Your Attic
This page looks at some of the ways that all that heat up in the attic might be used productively. This includes recovering heat for domestic water heating, space heating, pool heating, and cloths dryer air preheat.
Some of these look fairly practical (to me).
I've been logging the temperatures up in my attic for about 6 months and the plot of these temps is included. We live in a very cold climate, and it still looks like there is some potential.
Details here...
Recovering Heat From Shower Water Drain Pipes
This page looks at all the energy we send down the drain when taking a shower, and in some of the ways that are currently out there to recover some of that energy.
It considers one (as far as I know) new method, which is basically to rearrange the drain plumbing to retain the shower water in the homes heated envelope long enough to recover the heat in the water for space heating.
Some ways of doing this, the resulting energy saving, and a small test to examine the potential of this method are discussed.
It may seem like there is not really much potential here, but for heating climates, the potential energy saving for a family might be of the order of 1200 KWH a year.
Details ...
A Very Energy (and Water) Efficient Shower Design
This is a look at a shower design that was looked at for potential use on very long range commercial jet airplanes. It is a very efficient design both from a water use and energy point of view. It may not be for everyone, but have a look.
Details...
So, I'm particularly interested in whether you think any of these ideas have some merit and are worth pursuing (or not).
Or, maybe you have some of your own "Out There" ideas you would like to share?
UPDATE: Turns out Kenneth has built and uses a recirculating shower...
Kenneth's interest were more in getting long showers with very high flow (6 shower heads) without breaking the bank on energy use. Its a nice simple design.
Note that Kenneth has also done a very nice Solar Shed project that does both solar space and water heating -- hope to have the details on this up soon.
Thanks Kenneth!
Gary