This was a major design for my diploma porfolio. Making use of a south facing wall to harness solar energy whilst tapping into the wasted heat and greywater from our shower. The thermal store tank on the wall takes shower water and holds it in over frosty nights to keep the temperature above frost free, which it has done even when -9 degrees C outside. The water flows outside to a small scale reed bed which inturn irrigates a small hazel coppice bed in the front garden. Recycling our old windows, shower door and a friend's wardrobe shelving has been very satisfying, especially as we now get fantastic peaches and a frost free environment for seedlings. The development of the reedbed system from the original set up described in the diploma write up has made things even simpler. The reed bed needs very little maintenance - here you see them having an annual hair cut, and I've even found a creative use for the reeds!
If you are interested in learning more about installing a similar system, let me know via the contact page.