A first question the team asks is 'Why do we need water in our building?'. Some evident reasons are: to cook, drink, clean, flush the toilet en to heat or cool the building.
A distinction between primary functions made by this team is as follows. Water needs to be gathered, it needs to be treated or purified and delivered to the place where it is needed. Besides this, it is possible that the water will need to be stored.
A quick estimation by the team results in a consumption of 80L of water per person per day. On the other hand, there is only an average precipitation of 2L of water per m² per day. This means that there will not be enough water purely due to precipitation. To obtain more water, a connection can be made to an external water delivery system or water can be produced (recycled) to make the building self-sufficient.
The main objective of the water treatment is to make drinkable water. This is difficult since different kind of contaminants exist: debris, mechanical contamination, chemical, .... Inspiration from nature for water treatment is seen at Baleen fish filter and aquaporin membrane technology.
For the delivering the water different principles can be used. Here a distinction is made between the upwards and downward movement of the water. Gravity can be used for the latter one. For the upwards movement, a capillary faucet can be used or the effect of transpiration can be incorporated.
Water will also be used for regulating the temperature. Here for hot and cold water will be circulated through the building. Heating of the water can be obtained by a sun-boiler or by the use of geothermal energy. Cooling of the water is done by the principle of transpiration by using the wind.
To conclude, the building has to be self-sufficient for its water usage.