Solvatten: The Water Container Which Harnesses the Sun to Purify Drinking Water

A couple of years ago on CBC (Canada) Radio I heard an inventor interviewed who was working on a combination of clay/silver for water purification - a very cheap solution. I remember him being sponsored by the Rotary Club. Can't seem to find anything more on it. Sounded very promising.

Is there any way we can help get these to people that need them?

If this can be produced cheaply around the world, this concept will probably save many lives. It's brillant! Thanks for posting it.

Uh, unless this thing uses UV light to kill pathogens, it's worth noting that there's lots of harmful bacteria that just *love* temperatures between 40C and 100C.

You would be better off boiling the water, IMHO. And even that doesn't remove nasty pollutants.

Where is the water widget (Slingshot) from Dean Kamen?

A water cleaner and generator, Dean has been pushing this for years - yet none is to be seen. I would think the US Army would have purchased these in job lots.

The device shown here is nothing I would use, but - to each his own.

Good to have a larger container and a manufactured process but you can do the same thing with a plastic bottle and then you can improve the performance of the plastic bottle with a reflector made from snack food bags turned inside out (to expose the aluminized mylar surface) as two schoolchildren in Brazil have demonstrated.

It seems that this is a 'high-tech' variation of solar water disinfection described in http://en.wikipedia.org/wiki/Solar_water_disinfection

According to Wikipedia, the reason it works is:

* UV-A interferes directly with the metabolism and destroys cell structures of bacteria.

* UV-A (wavelength 320-400nm) reacts with oxygen dissolved in the water and produces highly reactive forms of oxygen (oxygen free radicals and hydrogen peroxides), that are believed to also damage pathogens.

The indicator showing sufficient time helps make sure there is less human judgment involved in the process.

Its says it uses the synergistic effects of UV radiation plus the 55C temp. Watch the video before commenting, dolt.

Ernie. . .I took a second to look at their website and it says,

"SOLVATTEN uses the idea of combining heat, UV and built-in filter in a specially designed container to clean contaminated water"

The website also talks about how by heating the water using sunlight it saves firewood which is a huge issue as well e.g. Haiti

maybe if they boosted the temperature with parabolic mirrors closer to boiling, they could get even better results?
Anyway, this is device can be used as a water heater aswell, so it can be very useful

If I'm not mistaken, you can buy a hand-operated water pump with ceramic or other filter that filters out most or all pathogens - they sell several types at our local camping supply stores. Maybe a solar water purifier is cheaper to make or operate, but wouldn't these camping-type filters work just as well?

Then you'd have COLD water to drink when the process was done. With the solar system you have to wait quite a while for it to cool. I guess we could combine this with a low-tech solar refrigerator like the one TreeHugger featured a few months back.

Robin - available in wealthy countries, yes. Available or practical for 3rd world countries, no. The ceramic filters clog easily, require maintenance, and only filter a few hundred gallons before you must replace them. Great for quick hydration on the AT in the US. The solar option is much better day-to-day for millions of people who can't afford to fiddle and replace. Just insert water and go, come back later and drink.

The Solvatten purifier may be news, but it's not actually new. In August of 2007 we posted on the very similar Solar Bottle that won the Danish Index award that year. Designed by Alberto Meda and Francisco Gomez Paz.

I am sort of involved in Solvatten...
The great thing with it is that is works to 99.9% in removing all the harmful bacteria. Hence it does not need to be more effective. It works when it is cloudy, but takes a bit longer. As long as UV lightning gets through.
The indicator is central since it helps people to know when the water is clean and safe.
It is very efficient and takes about 3 hrs to clean 10 liters and can be used over and over again, several times a day for many years.
Our biggest hurdle now is production cost which makes for a relatively high initial cost when getting it to the people who need it (though the cost/liter of clean water is very low over the years it can be used). But are working on this and things are on its way!
It is basically an upgrade of the SODIS program (as some mentioned), which makes it more expensive, but also cleaner water, more efficient, and more acceptable among the intended users, with the right can of sponsorship, this can save millions!
if you have any questions or suggestions. please get back to me.

Erik

Aside from the usefulness of the filter, any clear plastic bottle can use UV rays to purify water in 8 hours of sunlight in the same way, and is much more accessible to people in developing regions. It also is a good way to repurpose plastic water bottles.

The plastic bottles are a great way to make use of plastic bottles and to make water cleaner cheaply and should applied in as many places as possible.
Having this said, the use of plastic bottles to purify water has been problematic for two reasons. First of all, as i understand it, it is hard to implement. People do not see the point of putting water into bottles in the sun and then, after a while, drink it, when they can just drink it straight away. It is hard to understand the actual process (the UV) which goes on - so they just skip this step and drink it straight away.
Secondly (which also contributes to the first) purifying water in plastic bottles with the help of UV, is not very effective and most importantly it is uneven in its success of purifying and no indication if the water is purifies or not. With different seizes of bottles, different amounts of sun, no turbulence in the water, it might not be clean when you think it is. This leads people drinking water from the bottles to think it does not work (and there is a risk of regrowth of bacteria in the water).
The SODIS program is a very cheap process of cleaning water, but its implementation program is very expensive and challenging. Solvatten is not as cheap considering the initial cost of acquiring it, but is much more effective and cheap, in the long run.
I do not think we have to choose one from the other, I think both have their advantage and disadvantage.

Hello, I just heard about this on CNN. This would be great for me and Tonnes of people I know. We are constantly on Boil Water Alerts. I can't seem to find the web-site for the company that makes these things and I have some questions on how well it would work at removing things like lead, not just bacteria.

If someone could please get back to me.