How to reach to net-0 water building

In my last blogger, I mentioned that algae cell may use brown water as its nutrition solution. That makes me think that whether we can reach to Net-0 water building through this processing which is another factor of reach green building. ( for example, LBC (Live Building Challenge) evaluation requires green building to be Net-0 building) 

In Florida, annually rainfall is about 50-60 inches. Most of the water goes into or under ground. Storm water are not portable in any culture, but they are not "dirty". We may use it for toilets and urinals flushing, irrigation or the fire sprinkler system so that valuable portable water can be saved. However, that's not enough to reach "Net-0" water building. We may want to go deeper on how to use these storm water. ( the amount of storm water is not a factor to be worried about in Florida but some other "water shortage” states such as Nevada.) 

If storm water is the only water resource other than tap water, and we have plenty of them, The first thing to do is to make it portable. A technology called membrane bio-reactor (MBR) can help reach the function. 

After purifying processing, we will have totally portable water. Next step will be how to treat the waste water. (because gray water and black water are too dirty to treat by MBR) We should at least transfer the gray or black water into the same cleanliness as storm water so that it won't pollute the nature (also can be recycled if necessary). We may use "Living Machine" to reach that goal: use soil and plants (algae mentioned before is also counted as plants) as first purifier:

As the a system, it should look like so:

   It is only a concept of how to achieve Net-0 water building in Florida. Further research and feasible reports will be needed.  

Multiple ways of getting Net-0 energy building

No matter which green building evaluation we are using, LEED, green globe or LBC, energy consumption is one of the biggest concern. In fact, LBC requires net-0 energy building in its requirement. PV panel maybe the most available products to reach that point, however, its low efficiency and high cost encounters a lot of critics. Not to mention its CO2 emission in it's producing.

Truly, solar power is the only energy resource for the world, but there are multiply ways of storing this type of energy. Our nature world gives an perfect example about how to transfer energy and the idea is becoming realistic. For example, algae solar cells:

Algae is widely existed in nature. After direct or indirectly lighting, they will produce a product called SVO or straight vegetable oil which can be transfer into bio-diesel later. In this processing, it absorb CO2 and emit   O2. This is also the basic idea of algae solar cell. In the processing, only water and CO2 are needed. Algae is 3 times efficiency than PV products; And if treated correctly, we may use brown water instead of using portable water. Biomass left will total green.

The first Algae building is located in Germany.  "A 15-unit apartment building has been constructed in the German city of Hamburg that has 129 algae filled louvered tanks hanging over the exterior of the south-east and south-west sides of the building—making it the first in the world to be powered exclusively by algae. Designed by Arup, SSC Strategic Science Consultants and Splitterwerk Architects, and named the Bio Intelligent Quotient (BIQ) House, the building demonstrates the ability to use algae as a way to heat and cool large buildings."

Compare to traditional PV products, the system may have some short legs: 

1. it's not generating electrical but bio-diesel which is considered as a lower level of energy. There will be some energy lost if transferred into electrical power.

2. More complex system and cost more on maintenance.

3. Special environment control required. 

4. Not mature marketing yet

...

At least, it opens our minds on how to utilize solar energy besides PV technology.