capturing heat from grey water

We've considered using compost to heat water, but what about using our hot grey water to heat our fresh water right in the pipes?

This Ecodrain product uses hot water going down the drain to heat water for your shower, so the water heater has to do less work. A more basic version of this has been used in many buildings, which involves wrapping the copper pipe holding fresh cold water around the drainage pipe, trying to capture some of that used hot shower water's heat.
This company created their product to more efficiently capture and redirect that heat. Their website is very thorough and informative, so please check it out for more information on specifics.

http://www.ecodrain.ca/

In the house system we could very easily connect the hot water from the compost where the water heater is in this diagram, and fresh water collection/filtration where the 'municipal supply' is indicated.
If you are bathing Japanese style like Rachel this may not be necessary, but it's a very cool idea for showering.

Compost powered water heater

This is a video of a group of people testing out their compost powered water heater- which is pretty thrilling for us, as we've been chatting about an almost identical model for a while now. It's very exciting to see it working and to know that there's someone I can contact to ask about it.



Here is a diagram of the model they've based their design on, designed by Jean Pain, who was hot stuff on the composting scene.

This is a great, terrible video. It's basically a blooper reel of a fellow trying to rig up a solar shower, so it's a pretty clear "here's some of the challenges you might deal with" instructional.

Water Pump. Applications Endless

Basically, the allure is the ability to pump a constant supply of water without the use of energy. Would necessitate a resevoir, but from the sound of things, this serves as an irrigation system for whoever made it, for gardening/farming. Basic idea is using hydraulics to pump water. Also has applications as a possible small power source, in addition to just being amazing.

Collect rainwater at height, cycle down to power hydraulic pump, run through turbine, collect energy, use water in garden/greywater applications, or filter and consume/bathe.

That piston driving the water pump could have a magnet attached, and a coil placed around magnet to gather electricity, if turbining the output is not wanted. This would be a purely parasitic act, would not provide much but could power several LED lighting systems very easily for extended periods of time.

http://www.instructables.com/id/Worlds_greenest_water_pump/

Passive Heating and Cooling

Here's an interesting design which demonstrates some key principles of passive solar heating an cooling. It mentions the slate floor which acts as a thermal mass (slowing heating and cooling over the course of the day and night, respectively.) One of the ideas we've been tossing around is using the moss wall as our solar mass, as it's density may be appropriate. (We may want to consider adding a thin stone tile backing to it...)

I've also been reading the Humanure book online, and found the temperature that compost can reach- up to 70 degrees Celsius. This is pretty exciting, as we were also discussing an idea for a water heating system which would run a coiled pipe through the compost containment unit, and then through the central wall of the house. This would heat the house, as well as provide hot water. Any thoughts on how feasible this might be?