Comments on: Clean, Portable Power

by: Clean, Portable Power

Fri, 22 Feb 2008 16:15:25 +0000

[…] MEDDESKTOP wrote an interesting post today onHere’s a quick excerptPortable generators rule, but in some situations they aren’t the ideal power source. For example, you can’t use your noisy, messy, and fume… […]

by: Nate Bezanson

Sat, 12 Jan 2008 15:49:44 +0000

Simon, a few years out of a Costco battery is doing pretty well. As with everything else, in lead-acid batteries you frequently get what you pay for. Plate thickness, separator material, cell bottom geometry, rigidity and reinforcement against vibration, all these things affect the longevity of a battery that sees deep discharges and portable use. You can get ten or twenty years out of a very carefully designed lead-acid that’s kept on a rack in a temperature-controlled battery room. But in any sort of real-world portable use, 2 or 3 years is typical, 4 or 5 is truly exceptional.

My personal jury is still out regarding desulfators. I bought a nice VDC charger/desulfator and it’s been good to my batteries so far, but I didn’t see any of the promised gains after letting it work on my neglected batteries for a few weeks. I like the theory, though, and I rotate all my stored lead-acids among the desulfator because I figure it can’t hurt. (Though the RFI is killer, it gets unplugged when I’m on the radio!) You might try one and see if it prolongs the storage life of your batteries.

by: Simon

Sat, 12 Jan 2008 14:12:09 +0000

I have bought and modified many of these type of units and found the batteries tend to die within a few years. This was regardless of being trickle charged all the time or only charged after use. But they are cheap at Costco.

by: Jim K.

Fri, 11 Jan 2008 23:53:13 +0000

I started a project of DIYing one of these last fall and just haven’t quite finished it yet (got distracted somewhere between starting it and getting married). I’m planning to pick up on it again soon though and will post pics up to the flickr pool when I’m done. My plan is to go with a solar panel on it for recharging off-grid if needed. My first version won’t have quite as much battery run-time, but I got most of the pieces for free through various means so beggars can’t be choosers. BTW- truly depressing, comparing charging times of batteries via PV panels and run times of equipment off the batteries that are charged.

by: Benjamen Johnson

Fri, 11 Jan 2008 20:38:57 +0000

It depends on your load. Here’s a link to their run-time table

http://www.xantrex.com/web/id/63/p/224/pt/10/product.asp

While these don’t seem like very impressive numbers they are about what you’d expect. Batteries just don’t store that much energy per weight compared to fuels such as gasoline and natural gas — which is why we don’t have a really feasible electric car yet.

by: Geoff K.

Fri, 11 Jan 2008 20:31:35 +0000

What’s the runtime on a unit like this one?

by: Nate Bezanson

Fri, 11 Jan 2008 18:54:42 +0000

Xantrex makes top-of-the-line power packs, having absorbed both Trace (who used to make high-end residential inverters for off-grid applications) and Statpower (one-time kings of the sub-kilowatt market) and kept their quality consistently high. They’re not exactly cheap, but I think quality is worth paying for.

However, a portable power pack is an obvious DIY project for anyone who’s comfortable with high-amperage DC wiring. Find a wheeled toolbox or cart that’ll accommodate a 60-lb deepcycle battery, get a disconnect switch and some fuses, a pile of Powerpole connectors, a beefy inverter, and some jumper cables you can cannibalize. Your local car audio or amateur radio enthusiast can probably help with crimping and testing.

For extra credit, install a dual-battery isolator in your vehicle, and wire it so the second battery is in the rear cargo area. If it just so happens that the second battery is in a wheeled box and can be disconnected by yanking a plug, so much the better! It’ll stay charged when you don’t need it, and it can go with you when you do. Using one style of connector (Powerpole SB300 make a good choice) for the disconnect and the jumper cables, and the optional jumper extension cable, will give you a really versatile setup.