[Chhanda Das]

DIY water purification system for use in cars

The pandemic got me thinking. How can we ensure that we drink safe water on trips ? I thought of carrying/buying mineral water bottles but those create plastic waste and are cost-prohibitive in the long term especially with my car-camping situation. Also, fake mineral water is not too hard to find. I thought of carrying the water from home but that increases the weight of the car, increases fuel consumption and causes more wear and tear on consumables like tyres, brake pads/shoes, etc. So I thought of making a drinking water purification system for my first-generation 1.6 Petrol Creta AT.

My resources are very limited. So I did not want to spend around INR 3500-4000 for a new system and instead converted my home water purification system into a portable one so that I can use it both at home as well as in the car as and when necessary. Additionally, a permanent setup would require changes to the RC and I am not willing to put myself through that grind especially at this ripe old age.

The raw water goes as follows :-
1) Spun filter or sediment filter to eliminate large dirt particles

2)Pre-carbon filter or chemi-block filter to eliminate bacteria, chlorine, odours, etc

3) Post carbon filter to remove rust, scale, etc

4) RO (reverse-osmosis) to remove ions, unwanted molecules and larger particles.

5) UV (ultra-violet) filter to kill/deactivate viruses, bacteria, protozoa, etc.

6)UF (ultra-filtration) to remove suspended solids, bacteria, viruses, endotoxins and other pathogens.

7) Mineralizer to add essential minerals like magnesium, calcium, etc while maintaining the required pH level

For the electrical and water connections, please have a look at the images and video below. The changes to the stock filter are as follows :-
1) Removed the float switch due to absence of proper reservoir

2) Installed locking clips on all connectors on all possible sides to prevent leakage in a moving car

3) Removed the transparent cover to reduce weight. I could have removed the base and the back as well but decided against it to prevent plastic parts from touching the pump as it gets hot during use.

4) Removed the water reservoir to prevent water splashing/dripping inside the car

5) For the reservoirs, I used 2 litre soft drink bottles for the raw water, drinkable water and waste water. I drilled their caps and installed 1/4 inch bulkhead connectors on them.

6) Stop valves were added at necessary spots to prevent the water dispenser from pulling impure water.

7) For the mounting, I placed it in a bag and hung that from the front passenger seat's back.

8) I powered this through the pure sinewave inverter in my car. Power consumption is around 72 watts after accounting for efficiency/conversion losses for the 60 watt rated system. I could have powered this with a 12v to 24v DC boost converter but decided against it as it would push up the costs substantially.

Total cost was INR 510 and this includes the extra connectors (elbow, T and bulkhead), stop valves, the locking clips and the usb rechargeable pump / water dispenser ...

Water flow diagram

Electrical wiring and connections

Yay, it works

https://www.youtube.com/watch?v=6J9ZySm6NfE

[Aditya]

DIY: Water purification system for use in cars - Post moved to a new thread.

[ABHI_1512]

Commendable indeed, the pandemic situation has got people thinking and they in turn are coming up with never before installs. Few days back, someone installed a toilet inside a Toyota Fortuner and now this water purification system inside a Hyundai Creta.

I know how you have done many such DIY’s installations in your car since you prefer the camping style of travel. From the video, it looks like the second row of seats is unusable after the installation. Also, these days, RO filtered water is available across the highways as I have found during my journeys. I also carry water bottles from my home and refill them from trusted fuel pumps and hotels on the go as and when necessary.

This DIY although useful looks cumbersome with so many pipes around. But then, that’s my view entirely. Nevertheless, since getting filtered drinking water while camping is your idea, if it works for you then that’s a job well done.

[Chhanda Das]

Originally Posted by ABHI_1512

Commendable indeed, the pandemic situation has got people thinking and they in turn are coming up with never before installs.

Nevertheless, since getting filtered drinking water while camping is your idea, if it works for you then that’s a job well done.

Thank you very much for the kind words. You are absolutely correct about the cumbersome part. However, the video is from the very first testing of the setup and we were unsure of whether it would leak or not which explains the bucket. I have since cleaned up the setup to enable the bottles to be placed inside the seat pockets at the back of the front seats. So the bucket is gone. And the piping setup is a lot cleaner too now. The second row of seats remains usable irrespective of whether the bucket is there or not. I plan to install a portable bucket-style toilet there once I can get my hands on a good ventilation fan but sadly Aliexpress is banned only in India now

Sadly, I have had some bad experiences with drinking water from places that claim to have RO but in reality, the devices are either not maintained properly or they refill those filters straight from taps with impure water. So I do cannot trust them anymore

[Jaguar]

Originally Posted by ABHI_1512

This DIY although useful looks cumbersome with so many pipes around. But then, that’s my view entirely.

That is my view too. And moreover, what will happen in the event of a crash? If a passenger manages to squeeze into the second row, this could be fatal. And the cost mentioned does not include the cost of the original RO system. The logic given is that the same system can be used both at home and in the car. But then, does that mean that everyone in the house will go for a road trip together, always? If not, what will the folks at home use? Then there is the practical aspect of carrying it back & forth and assembling it in the home after each trip. Too much jugaad for too little ROI IMO. There are multiple water-purifying methods used by backpackers and campers, which are simpler and can work for the car too.

[RedTerrano]

For the joy of DIY, very nice effort. Looks professional and neat.

For a more practical solution, I never leave for any trip without this trusty guy. I have been using it for decades since I was younger and loved trekking and rock climbing.



1 drop for 1.5 ltr and you are good to go in seconds.
Mediclor. Heartily recommended.

[Chhanda Das]

Originally Posted by RedTerrano

For the joy of DIY, very nice effort. Looks professional and neat.

Thank you very much for your appreciation. I definitely considered water-purifying liquids before the DIY but decided against them considering that it was not completely effective against certain germs like Giardia, etc unlike UV light. Additionally, such chemicals do have side effects and are completely ineffective against substances like heavy metals including arsenic, etc which is very common in the water of eastern India where I live. I wanted to be ready for all reasonable sources of water. Hence, the decision for a DIY RO+UV+UF setup with a TDS controller.

Originally Posted by Jaguar

That is my view too. And moreover, what will happen in the event of a crash? If a passenger manages to squeeze into the second row, this could be fatal. And the cost mentioned does not include the cost of the original RO system. The logic given is that the same system can be used both at home and in the car. But then, does that mean that everyone in the house will go for a road trip together, always? If not, what will the folks at home use? Then there is the practical aspect of carrying it back & forth and assembling it in the home after each trip. Too much jugaad for too little ROI IMO. There are multiple water-purifying methods used by backpackers and campers, which are simpler and can work for the car too.

Your observations are definitely reasonable and not unfounded. However, the seat belts should do the trick. Also, there is no need to for the passenger to squeeze into the second row when I already mentioned above that the setup has been cleaned up a lot and I have tied the bag to the rear of the front seat. The bucket is gone too and the bottles can be placed on the seat pockets at the back of the front seats.

"The logic given is that the same system can be used both at home and in the car." I mentioned this for my situation obviously since my family is very small. A larger family will clearly require a dedicated setup. I also mentioned very clearly that my resources are limited and I did not want to spend for another or a new system. Just like with cars, there is no such thing as one size fits all.

"Then there is the practical aspect of carrying it back & forth and assembling it in the home after each trip." That is exactly why I had placed it in a bag and a bucket. I didn't want to spend much time in assembling/disassembling it. The bag can be hung near a washbasin at home and the bucket can be placed under it. Then it is just a matter of disconnecting the raw water inlet pipe from the bottle and connecting the pipe to the wash basin's inlet through the adapter which should have been installed already from earlier. The wastewater outlet can be hung or placed on the basin like earlier. All of this assembly/disassembly should not take more than a minute

[drsnt]

There are a lot of personal bottle purifiers available as well as chemicals that can disinfect drinking water. I personally use Aquaguard "On the go". Without undermining your efforts, your setup looks too complex when other much easier and portable solutions are available.

[Chhanda Das]

Originally Posted by drsnt

There are a lot of personal bottle purifiers available as well as chemicals that can disinfect drinking water. I personally use Aquaguard "On the go". Without undermining your efforts, your setup looks too complex when other much easier and portable solutions are available.

Thank you very much for your kind appreciation. There are definitely personal bottle purifiers and suitable chemicals but none of them are all-in-one solutions for every reasonable source of water. For example, I live in eastern India where heavy metals like arsenic, etc are very common in groundwater. Yet I cannot find any personal bottle purifier or suitable chemical to remove those which explains the motivation for my setup. About its complexity, I have cleaned up the setup since the very first test run shown in the video

[Altocumulus]

Originally Posted by Chhanda Das

I thought of carrying the water from home but that increases the weight of the car, increases fuel consumption and causes more wear and tear on consumables like tyres, brake pads/shoes, etc.

While this is a great DIY and your efforts are commendable, I am bit confused with the maths. So these purifiers are in no way lightweight, plus it's not that they will create water from thin air. You need water to purify it and most of it will anyways get filtered out as waste. So for the amount of weight you will be carrying around in this setup, i.e the setup itself, the input water, the waste water for getting a glass of water is additional load. Instead if you carry a 20L mineral water drum with the battery dispenser (about 500 bucks on Amazon)wont it save space as well as weight as well as a lot less hassle. The more you drink the less weight you will carry.

Your vehicle already has a lot of electrical accessories you are already running. Now you are adding more. You are looking at potential electrical or BCM failure. Not a great thing thing while on long journeys.

Sorry for being blunt.

[Chhanda Das]

Originally Posted by Altocumulus

While this is a great DIY and your efforts are commendable, I am bit confused with the maths.

Please, there is no need to apologize. Thank you very much for your kind appreciation. Your concerns are definitely valid. The total weight including the weight of the water inside this DIY system is approximately around 8 Kg which is way lesser than the approximate at least 21 Kg weight of a 20 litre mineral water drum. Additionally, the 20 litre drum's neck would stick up above the height of the rear seats after folding them down and that would prevent me from extending the bed towards the front seats since I am into car-camping as well. Also, that drum would be an inconvenience if I were to seat 5 people in the car and that is precisely one of the reasons why the bucket from the 1st trial video was removed.

"The more you drink the less weight you will carry." That is absolutely true but it is applicable for highway trips only where sources of potable water may be easily available. However, in the case of multi-day car-camping in the wild, the proposition is sadly not feasible due to the obvious lack of guarantee of the availability of potable water.

"You need water to purify it and most of it will anyways get filtered out as waste." That is not necessarily correct in all situations. It depends on the TDS (total dissolved solids) level of the raw water. If the raw water has high levels of TDS then a lot of it will get wasted while purification primarily to keep the RO filter clean. However, if the TDS levels are low, the wastewater can again be recycled through the raw water inlet thereby reducing wastage. TDS levels can be easily tested with a cheap TDS tester. Practically speaking, almost any water from rivers, wells, ponds, lakes, etc can be purified with this DIY setup and we can have the exact TDS level that we want by the help of the TDS adjuster. The TDS adjuster is nothing but a valve that controls the amount of water that goes to the RO filter vs the amount of water that bypasses the RO filter.

"You are looking at potential electrical or BCM failure" That is absolutely correct but I can assure you that we take the necessary precautions to prevent any untoward situations. My Creta has 12v 180 watt rated sockets which came stock with the car. Hence I took that rating as the maximum limit. After accounting for conversion/efficiency losses, I make sure that the total extra combined load of all the gadgets and devices running at the same time off the car never exceeds 150 watts at any given point of time. This way I can run an infinite number of gadgets. Also, none of the gadgets and devices that I use in the car are hardwired and they all use either USB ports or 12v accessory plugs. Touchwood, I have never ever had even a fuse blowout. And I make sure to never run these gadgets/devices while the engine is off unless their wattage is lesser than what my solar panel puts out to the battery