NPowerPeg report?

[Harrison Bergeron]

Anybody else ever heard of this thing: http://www.npowerpeg.com/ ?

It's a 9oz gadget that charges batteries by kenetic motion. It's been on the market about a year. If anyone carried one this year, how about a report?

I found it here, in a PCT hiker's journal: http://www.trailjournals.com/gear.cfm?trailname=10032

She says she was a beta-tester but it never worked. When she returned it they told her the battery was defective.

If they've got the bugs worked out, I'd sure like to know. This would be the ultimate solution to the smartphone power problem.

[Jayboflavin04]

John I have been keepin tabs on this company ever since I have heard about the product....I havent heard nothing either. I review would be great.

[M1 Thumb]

I haven't read one 3rd party review/test of the nPeg. Several sites push this product but no one has any hands on experience (if someone has, please post your thoughts). Until I see independent testing and results, I will keep this product classified as "suspect".

For a product you can believe in :

http://www.thinkofthe.com/product.php?name=anti-theft-lunch-bags

no more losing my sandwiches to the wily homosapien :D

[4eyedbuzzard]

Here's the real world physics.
A typical good quality disposable battery has approx the following capacities and specs (estimates, there are some differences in manufacturers claims, etc):

AA alkaline 2000 mAh 24 grams
AAA alkaline 1000 mAh 12 grams
AA lithium 3000 mAh 16 grams
AAA lithium 1500 mAh 8 grams

These are approx. capacities in low load / low drain application of 25mAh or so. Flashlight and photo use will reduce battery useful life substantially (as much as half), but lithiums suffer far less than alkalines especially at low temperatures.

The PEG's internal battery has a capacity of 1000 mAh, so at their specified power generation rate of 500 mAh it will fully charge its internal battery (approx that of a single AAA) in 2 hours. The problem now is that to continue storing energy, that energy must be transferred to another storage battery, or the internal battery of an iPhone or camera must accept that charge. Once you reach the charge capacity of all the batteries you have, the PEG becomes dead, non-functional weight.

Lets say you hike and walk around approx 12 hours per day, generating the full 500 mAh for 12 hours. You'd generate 6000 mAh of power. You'd have to store 5000 of that in batteries other than the PEG's. The best way would likely be NiMH batteries. You'd need 3 AA's minimum at 27 grams (1 oz ) each. Now you're carrying 12 oz for the PEG + 3 oz for the NiMH batteries + say 3 oz for a NiMH charge adapter and cords. That's 6000mAh of available power at a weight of 16oz (1 pound). Comparably, two AA lithiums or even three AA alkaline batteries will store and provide the same amount of usable power at 32 grams and 72 grams respectively. And there are plenty of cheap "emergency" phone battery rechargers that will work from AA's at perhaps 2 oz or so.

The PEG retails for $150. Add another $30 or so for NiMH's and a transfer charger of some sort. Unless you are using up several AA's per day and cannot resupply for 5 + days at a time, you can buy a lot of regular batteries at that price and more importantly for most hikers - save carrying close to a pound of additional gear (the PEG and misc stuff). For most hikers, the economics (factoring in both weight and cost) of the PEG just don't make sense. Perhaps once the price comes down, and better and higher storage capacity is available, the technology may make better sense for hikers.

Just my opinion. :o

[rusty075]

The likely reason that you're only seeing marketing reviews of them, and not real-world reviews is that they're having a heck of a time actually producing them. I ordered one back in May, order #200-ish, and I'm still waiting.

Ordinarily I'd be frustrated to the point of anger but I'm cutting them some slack, at least for now. They're a tiny little tech startup in Ohio who making something completely new, and are sourcing all of the parts and labor domestically. They could have a factory in India cranking these things out by the boatload, but instead they're relying on the US producers of things like the lithium-polymer battery, for which there are very few companies that make them here anymore. It's like cottage industry backpacking gear, except that instead of nylon and sewing machines they're making things out of lithium-polymer batteries and circuit boards.



The PEG's internal battery has a capacity of 1000 mAh, so at their specified power generation rate of 500 mAh it will fully charge its internal battery (approx that of a single AAA) in 2 hours. The problem now is that to continue storing energy, that energy must be transferred to another storage battery, or the internal battery of an iPhone or camera must accept that charge. Once you reach the charge capacity of all the batteries you have, the PEG becomes dead, non-functional weight.

Lets say you hike and walk around approx 12 hours per day, generating the full 500 mAh for 12 hours. You'd generate 6000 mAh of power. You'd have to store 5000 of that in batteries other than the PEG's. The best way would likely be NiMH batteries. You'd need 3 AA's minimum at 27 grams (1 oz ) each. Now you're carrying 12 oz for the PEG + 3 oz for the NiMH batteries + say 3 oz for a NiMH charge adapter and cords. That's 6000mAh of available power at a weight of 16oz (1 pound). Comparably, two AA lithiums or even three AA alkaline batteries will store and provide the same amount of usable power at 32 grams and 72 grams respectively. And there are plenty of cheap "emergency" phone battery rechargers that will work from AA's at perhaps 2 oz or so.

The PEG retails for $150. Add another $30 or so for NiMH's and a transfer charger of some sort. Unless you are using up several AA's per day and cannot resupply for 5 + days at a time, you can buy a lot of regular batteries at that price and more importantly for most hikers - save carrying close to a pound of additional gear (the PEG and misc stuff). For most hikers, the economics (factoring in both weight and cost) of the PEG just don't make sense. Perhaps once the price comes down, and better and higher storage capacity is available, the technology may make better sense for hikers.


I think there's flaws in that logic. One is that there's no need to carry more battery capacity than you're using in a day. You'd never carry extra rechargable batteries just to capture the "potential" energy. Instead you'd just attach whatever device you were carrying the PEG to recharge to the PEG directly and let it replenish whatever charge was lost from the day before. As long as that device was recharged by the end of the hiking day, the extra charging capacity lost doesn't matter.

Two, where something like this would likely be used isn't in recharging AA batteries, which are easily replaceable in town, but in charging things like cellphones and GPS units that have internal batteries. Recharging one of those from AA's isn't as clear-cut as you'd think. The storage values listed for rechargable AA batteries aren't an apples-to-apples to comparison to the output of the PEG. The PEG's 500mA output is at the USB standard 5 volts, which is what devices like a GPS require to charge. If you parallel and step-up the 1.5v output of a pair of AA's, and draw from them at .5A you discover pretty quickly that the resulting recharging capacity is nowhere close to what the listed capacity of the AA's is. A pair of 2800mAh AA's will actually provide only about 1000mAh of output at 5v.

Comparing the PEG to carrying batteries is like comparing a hobo stove to an alcohol stove: the hobo/PEG is heavier initially, but as the days between resupply increases the fuel/batteries weight of the alcohol stove adds up, while the hobo/PEG stays the same. If you've got 2000mAh of battery usage per day in your GPS/cellphone you'll be draining 4 AA's per day, at 1oz each, to keep it running. Factor in the charger at 3oz, and at anything more than 2.5 days between resupply the PEG is lighter. (not to mention that you're either going to be leaving a trail of dead batteries along the way, or waiting overnight at every resupply for your stack of AA's to recharge)

[4eyedbuzzard]

Agree on the volt amp correction - thanks. And I think it's a promising technology (though not a completely new one - there have been a few similar entries into this potential market in the past like the one that fit into a pack frame).

But as discussed in another recent thread on "how popular is long distance hiking?" - it isn't. To get the economy of scale needed to make this commercially viable the market has to be way bigger than LD hikers and people on "walkabout" for whatever reason. For section / weekend hikers for whom a single charge or set of batteries will last the length of their outing, it's a very tough sell at $150 + weight carried. And in daily life (the big market), people are almost always somewhere near a recharge source at some point each day, be it home, car, etc. I think the price has to come down and the power output come up. At the present, it can't keep up with the constant current drain for all but the lightest loads (an iPod nano is what they state I believe). So I think there is potential, but it needs development, refinement, marketing, - all the usual suspects.

[rusty075]

You’re spot on about the market size. If anything you’re over-estimating. It’s not just LD hikers – it’s LD hikers that have high enough battery use on-trail to make carrying the weight worthwhile. Even among though of us who do go out for 4-5+ days most aren’t using electronics enough to require on-trail recharging. No, if they’re smart even though it may have been invented by an AT hiker they would be marketing it to people like equestrian trail-riders, geocachers, surveyors, SAR’s, and the like – people who either aren’t as weight conscious as a backpackers or are more intensive users of electronics. They have an uphill battle, most definitely. But then again, people like Solio and Brunton seem to stay afloat selling solar products of similar price, weight, and electrical output, so anything is possible (if they can actually get product out into the world). The real long-term direction of their idea isn’t for milliwatt backpack power generators, which are basically a novelty, but for kilowatt wave energy generators.


They’re a tech startup, and the technology will hopefully follow the usual path of successful tech start-ups: Brainstorm an idea -> Get a patent -> Get some evidence of marketability -> Get the patent bought by someone bigger who will actually mass market the idea.