Carl, I don’t know exactly how much horsepower your arm generates when pumping a water filter. But I’m pretty confident about one thing: The motor and battery power required to duplicate that would be significant, and likely would add five pounds or more to your load. Besides, what would you do on a long trip?
MIOX Purifier
So, the short answer is this: No, there aren’t any battery-powered water-filtration systems out there.
As for a longer answer: Carl, there’s a reason it takes some effort to filter water. The pump action pushes water through an extremely fine filter, fine enough to catch tiny little creatures you can’t possibly see with the naked eye. So of course it requires some effort. For my part, I worry when a filter DOESN’T require much pushing, as I then figure it’s really not doing much filtering. I’m not sure what MSR filter you have, but I often use an MSR MiniWorks ($80; www.msrcorp.com) and find its pump handle gives me quite a bit of leverage, and at a comfortable angle.
Meanwhile, you could try this: MSR’s fairly new MIOX Purifier ($130). It’s the size of a fat pen, and uses camera batteries and salt to create a powerful bug-killing compound that is added to untreated water, eliminating viruses, bacteria, Giardia, and Cryptosporidium. No pumping needed!
Read more reviews of the best water-filtration systems in Outside‘s 2004 Buyer’s Guide.