# Fresh Drinking Water

1. Aug 5, 2009

### Pupil

http://www.ted.com/talks/michael_pritchard_invents_a_water_filter.html" [Broken]

I thought this was a neat little video demonstrating an idea that might save a lot of lives and people from the dread that is diarrhea. I sort of want one! :P

Last edited by a moderator: May 4, 2017
2. Aug 5, 2009

### humanino

You want one... what ?

3. Aug 5, 2009

### mgb_phys

Although his lifesaver bottle does compete with this http://www.vestergaard-frandsen.com/lifestraw.htm [Broken]

Last edited by a moderator: May 4, 2017
4. Aug 5, 2009

### Sorry!

£169.95 ... not cheap heh. I wish someday someone will use their personal resources to build something like this FOR FREE for people who need them.

5. Aug 5, 2009

### mgb_phys

Hiking pump water filters start at $50-60 and last for years. The lifestraw is$5 in bulk for NGOs.

For 3rd world countries a village scale water filtration plant is more cost effective.

6. Aug 5, 2009

### junglebeast

The filtration size of this unit you just posted is 200 nm, allowing both bacteria and viruses to go through, compared to the Lifesaver which is 15 nm, which does not allow either to go through.

The filtration size of the Lifestraw is even larger, at 15000 nm.

Wow, it's like you didn't even watch 10 seconds of the video before shutting it down...

There's a reason this is a TED talk -- it's something new, and he explains that for \$20 billion dollars (which is the amount that the UK spends annually), every person living in a 3rd world country could be given a renewable source of 100% virus free water without chemicals.

Last edited by a moderator: May 4, 2017
7. Aug 5, 2009

### mgb_phys

The ceramic filter in pump style units is small enough to stop bacteria, there aren't many bacteria under 0.2um. The straw ones have larger pores because you can't suck through a 25nm filter, they use iodine and chlorine compounds embedded in the filter to kill bugs.

The lifesaver is clever technology but isn't the most appropriate for the third world use that the OP was talking about. They are expensive and have a limited life, complex filter systems are also generaly susceptible to damage, you get one tiny hole in the filter and they are useless. They are aimed at westerners who are scared at the idea of 'chemicals' in their water.

8. Aug 5, 2009

### junglebeast

But not viruses.

If they are not appropriate for the third world, then why did the creator of this product focus his entire speech about having specifically designing this product FOR third world countries?

It still does not sound to me like you've listened to the presentation. Why comment before listening?

9. Aug 5, 2009

### Sorry!

I dont know if YOU listened to the presentation. It came with a 8 BILLION dollar price tag. IDK about YOU but if I felt that my product had any chance at making life for 3rd world nations easier, how ever remotely small or ineffective that may be, for 8 BILLION dollars I would try to sell it.

10. Aug 5, 2009

### junglebeast

The product didn't have an "8 billion dollar price tag", he said it would cost a measly 8 billion dollars to meet the GOAL of reaching 50% of needy people. Then he noted that for 20 billion, 100% of needy 3rd world people in the world could be helped, making the problem essentially go away entirely. 20 billion dollars is petty change for a government, and if multiple governments are already spending upwards of 20 billion on this problem annually with negligible returns...then this seems like a hell of a lot cheaper and more effective solution. Obviously, it is not required to purchase in such large quantity, but if the intention is to help people...and the government is already spending money...wouldn't it make sense to have them actually put the money where it makes a difference? What's wrong with having a percentage of those profits go to the person who's manufacturing the product which is saving millions of lives? That's how an economy works.

11. Aug 5, 2009

### Pupil

Didn't you see my post? I want a smiley face with the tongue stuck out. See:

:P

12. Aug 5, 2009

### mgb_phys

It kills more than the EPA require

Because to a TED audience helping the 3rd world is a better pitch than mentioning the military application which are their main customers.

13. Aug 5, 2009

### Pupil

The filter system has a safety device that will trigger if the filter stops working (i.e. if it gets a hole or something).

Just because their main consumers are in the military says nothing about the intention of the inventor (who specifically says in the video he created the filter for 3rd world uses). It might be that the technology hasn't caught the eye of large charities. It shouldn't matter even if his intention wasn't for third-world countries -- whether it works or not and whether it's a feasible solution for getting the third world water has nothing to do with his intention.

14. Aug 5, 2009

### HallsofIvy

From an old backpacker: There are no affordable water filters that will filter out all bacteria or all viruses. But any good water filter will filter out giardia and crytosporidium, the most dangerous bacteria (to a back packer). Iodine will kill viruses but not giardia except with quite a lot of iodine (which can be dangerous if used for an extended period and for pregnant women) and probably not cryptosporidium. However, a good filter that has been impregnated with iodine can filter out the bacteria and kill the viruses with the iodine. It isn't perfect but I figure I'm more likely to be hurt in a traffic accident traveling to the trail than to have a problem with filtered water on the trail!

15. Aug 5, 2009

### Sorry!

You were acting as if the sole intention of this presentation is merely to save. I'm pointing out that they are in it to make money.