This Rube Goldberg contraption is my reverse osmosis water filter. I have the water tank hooked up to a portable power station’s air compressor, via the Presta (bicycle) valve at the bottom. I use this to pump the pressure inside the tank to 65PSI.
The outlet hose at the top is connected to the intake valve of the filter. The outlet valve that would normally go to the dedicated RO faucet on a sink is simply draining into a pitcher.
It works. Once everything was ready to go, I opened the valve on the pressure tank (which had about 1.5 gallons of water in it) and in ten minutes or so, I had a half gallon pitcher full of Reverse Osmosis filtered water.
It’s a pain in the ass. In order to fill the tank, you have to block the Presta valve open, otherwise you can’t get water to go into the tank in the first place. I used a one liter plastic soda bottle with a pointed tip (think a catsup or mustard squeeze bottle) that would fit into the opening on the top. It takes about twenty minutes of squeezed, refilling, and squeezing some more to get the water into the tank. Once there, though, it was easy. Just switch on the pump, get the pressure up, open the valve, and watch the pitcher fill.
It’s sustainable. A few backup RO modules, and recharging the power station from the solar panels, and you should be able to process water for five years or so, as long as you keep your battery in good shape. (Discharging the battery by 20% or so, then recharging it every few days will make it last much longer than the usual rating).
But compared to the Berkey, it’s bulky, clumsy, and dependent on that pump (yes, a plain vanilla bicycle pump will work – it took me more than 500 strokes to get the pressure up to 45 PSI). The Berkey is pure setup and forget – pour water in, get water out of the same quality as distilled water.
Yeah, I’m talking myself into the Berkey. At least if I buy it, I can set it on the kitchen counter and use it everyday for drinking. And the combination of the Berkey and the solar still, the nearby Bay, and some storage and rain barrels should pretty much guarantee me good water for years, no matter what happens.
I’ll probably box the R/O back up and stick it in the shed for use as a backup, if needed.
UPDATE: Turned it around on craigslist this morning. Ordered a Berkey Light instead.