Showerloop is a water filtration and purification system that recycles shower water in real time allowing you to shower with hot water for a long time but only use 10 liters of water per shower (normal shower = ~6-10l/min) and a fraction of the energy (around one tenth) compared to a normal shower. The device can be installed inside or outside of a shower stall or bathtub. The main components are a pump, sand and activated carbon filters and a UV-lamp. The system weighs around 20kg and is made from transparent acrylic, steel or plastic pipe connectors and copper, plastic or rubber tubing.
The total cost of the most simple version has cost me around 600€ (~$655 US) depending on availability and pricing of local materials and the components used.
The filters can last as long as two years (but more like 1 year) with daily use but depends on the behaviour and general dirtiness of the user/s. The sand filter can be washed, the activated carbon or AC can be regenerated but only at high temperatures > 500 degrees C or composted and the UV lamp should last for thousands of hours but can be recycled and replaced like any other CFL.
The basic build of Showerloop is incredibly modular in terms of placement, materials selection and aesthetics. The only constraints come from the ideal filter dimensions and the power output of the UV lamp both of which are explored in the bachelor thesis ShowerMagic : A Hygienic and Eco-Efficient Real Time Greywater Reuse System for Showers found here: https://www.theseus.fi/handle/10024/76148
If you will build, built or are manufacturing Showerloop's or something based on this document please help us to continue working on it by donating to us, buying the KIT or parts or otherwise partnering with us. Without your support we will work our butts off to help you save the world!
Because the water should always be cleaned 100% or as close as possible the table NTU Reduction (%) above should be consulted if using different dimensions for the filter. NTU stands for Nephelometric Turbidity Units. It is a unit of measurement for the amount of particles floating in water. Drinking water has a value under 10 NTU, generally around 4 and visibly dirty water has an NTU over 15-20. NTU is measured chemically or optically. We have some design ideas for an open-source sensor, or several and would like some making them.
Although technically a 10W UV lamp can be sufficient for the removal of E.coli which is used as an indicator of water quality, other bacteria and viruses are much more potent and so we chose to use very high concentrations of UV light in order to create a safety buffer. According to our research the powerful lamp is more than sufficient in removal of bacteria even when the filters fail which means that even if the water looks, feels or tastes funny there shouldn’t be adverse health effects due to microbial action. If it does though, then it’s time to check, maintain or replace the filters. Using multiple UV lamps might be a good way to both ensure that the water is always bacteria free and all excess heat goes into maintaining water temperature.