{"id":8129,"date":"2023-02-02T07:13:04","date_gmt":"2023-02-02T06:13:04","guid":{"rendered":"https:\/\/era.archi\/?p=8129"},"modified":"2024-03-06T13:04:17","modified_gmt":"2024-03-06T12:04:17","slug":"greywater-harvesting-and-price","status":"publish","type":"post","link":"https:\/\/era.archi\/en\/greywater-harvesting-and-price\/","title":{"rendered":"Greywater harvesting and price"},"content":{"rendered":"

What’s way to harvest greywater for a positive house?<\/span><\/p>\n

\n

How to collect greywater in a positive house?<\/p>\n

What’s the price of collecting greywater in a positive house?<\/p>\n

May you don\u2019t know us yet, let\u2019s have a quick introduction: we’re ERA architects.
\nActually, I’m Esther Rovira, architect and passive house designer in Barcelona, Catalonia and Andorra for either passive houses, efficient houses and positive houses.
\nIn this post\u00a0\u2018Greywater harvesting and price\u2019<\/em>, You will find our professional recommendation.
\nI hope it helps you!
\nLet’s go!<\/p>\n<\/div>\n

 <\/p>\n

Greywater harvesting<\/strong><\/h3>\n

Greywater is the water that despite being sensitively used from showers and bathroom sinks, it could again serve some other use.
\nIt’s not recommended to re-use water from the washing machine, kitchen sink or dishwasher since they could contain massive amounts of oil, rest of food, cleaning products\u2026
\nIf you\u2019re thinking of recovering greywater, you may also consider not to have foam party in your bathtub too often.
\n<\/span><\/p>\n

The most common is to harvest greywater to re-use it for: toilet tanks, garden irrigation and cleaning (for example cleaning the floors or washing your electric car).
\nHowever you need to know three important things.<\/p>\n

HOW IT WORKS?
\nThis system consists of two tanks (usually located in the installation’s room)(note that there’s no underground system for this that we know yet).
\nGreywater is filtered to avoid rest of solids (like hair for example).
\nThen the bio-oxidation process brakes down the organic material.
\nStill in the first tank, the ultrafiltration membranes avoid damaging bacteria from going into the system.
\nBefore leaving the first tank a system of membranes suctions and separates liquid from the solids, virus and bacteria.
\nThen only treated water goes into the second tank where it is chlorated and storaged to be used.<\/p>\n

MAINTENANCE
\nThe first filter needs to be checked at least once a month to remove the hair rests and other solids.
\nThis filter is very similar to the swimming pool basket filters.
\nSo it’s not rocket science, but you need to remember to do this every month.
\nYou also need to clean the membranes every six months by using\u00a0sodium hypochlorite into the tanks.<\/span><\/p>\n

HOW MANY LITRES?
\nMind to calculate if your showers are coherent with your toilet use.
\nMeaning if you use the toilet more often than you shower, then you’ll need to feed your tank with paid water.
\nExample:
\nLet’s say showers harvest 30 litres and toilet flush take 6 litres.
\nThen we take a house with 3 people. Only one takes a shower once a week since the other two shower at the gym (1 people x 30 litres x 7 days= 210 litres).
\nBut all 3 use the toilet three times a day (3 people x 6 litres x 3 times x 7 days= 378 litres).
\nThen you’ll need to feed the toilet tanks with paid water.
\nOf course this is not very common, and usually the greywater harvesting is higher than its use.
\nHowever, mind to install an automatic weather to feed the tank with paid water, just in case all family becomes gym maniacs!<\/p>\n

So, let’s do a quick pros cons of greywater harvest:<\/p>\n

PROS
\n– collect greywater from showers and bathroom sinks
\n– re-use greywater for toilet tanks, gardening and cleaning
\n– save water
\n– save money<\/p>\n

CONS
\n– high maintenance
\n– if not used for a long time, then you’ll have problems
\n– occupies space system (not an underground system)
\n– occupies lots of space on the installation’s room
\n– no guarantees from manufacturers if not doing the maintenance<\/p>\n

PRICE
\n<\/strong>Market price of 1 water greywater filtering system with 500 litres\/day treatment capacity with a biological treatment is 4.500\u20ac+taxes (price of February 2024) (shipping included in Spain). Mind you\u2019ll also need to cover the installation price. Get 10% discount on this market price by filling in this\u00a0form<\/a><\/span>. Check data sheet here:<\/p>\n

\"greywaterfiltration\"<\/p>\n

Our professional recommendation:
\n<\/strong>We recommend to harvest greywater from showers and bathroom sinks to feed toilet tanks, garden irrigation and cleaning (floors, car, bike…).
\nMind to keep up with the maintenance once a month.
\nMind to shower accordingly to your toilet use needs.
\nMind not to do foam parties too often (greasy soaps exposure could damage the system).<\/p>\n

You may also be interested in:
\n<\/strong>Our other posts:<\/p>\n