Spring, 2012: The PowerGenX website popped up when I was Googling “portable solar generators” a couple of months ago. They didn’t list anything large as a 10K unit–just a CM-5K (Cart Mounted in 5K size) and a TM-5K (Trailer Mounted 5K). Even as frugally as we burn electricity, that would not be enough to fully power our off grid home.
However, I liked the 5K pricing (just under $5,000), the Options page that promised the availability of many possible upgrades, everything about the site…and I began to wonder.
Would Grover, the contact man at PowerGenX, be willing and able to double both battery storage capacity and solar panel size, mounting the components on a larger trailer…and Get ‘R’ Done for around $10,000? Because if so, he was going to have a new customer. We’d already been running on nothing but gasoline powered generators for more than three years. The “other best” option out there was ginormously overpriced at somewhere in the $50,000 range.
I sent Grover an email that same night.
He fired one back in short order and the Custom 10K, Border Fort version, was born. Turns out Grover Dobbins, the founder of PowerGenX and the man who’d be building the unit from scratch, was a mechanical engineer with more than 40 years of experience in the construction industry. He was (and is) also a great planning partner.
That’s right: Partner. I wanted multiple 20 amp circuits and lots of outlets; he worked in 4 of the former and 8 of the latter. My greatest concern of all was the inverter; he asked me to help search the far corners of the Internet for the best of the best. My research zeroed in on the Samlex 3000 watt pure sine inverter, industrial/commercial quality (the most rugged they make); he agreed and worked that into the equation.
Yes, the Samlex cost over $1,200–and I was more than happy to pay for the upgrade. We’ve had some really grim experience with the POS type of clunky garbage inverters.
Samlex! Samlex! Samlex!
Grover even decided to personally deliver the new portable solar generator, towing it over from his place in neighboring New Mexico to our homestead in southern Arizona. 411 miles one way, just $1 delivery charge per mile.
All told, the bottom line came out to a bit under $11,300.
Was I waiting on the water tower today, watching for Grover’s pickup truck to come easing down the dirt roads to reach our place like I used to wait for my aunt to come give us a ride to ye olde swimming hole when I was a kid?
Can you spell “zoom lens”?
As the truck and trailer pulled into our driveway, my focus was entirely on the arrival of our new portable power plant. Didn’t even notice the entirely gray-haze sky produced by various wildfires throughout the region.
Apparently I was not the only one who found the arrival of the PowerGenX Custom 10K portable solar generator (Border Fort version) to be of interest. While Grover was jockeying his truck into position to drop the trailer, a pair of crested flycatchers we’ve not seen here previously also arrived. They perched atop the old TV antenna that provided us with entertainment on a dozen channels in 2009.
Note: Grover may end up designating this one the TM-10K or some such. We’ve never discussed that possibility one way or the other. For now, though, I’m going with my much longer (and unwieldy) Border Fort version
Most great engineering designs–at least in my opinion–tend toward being both simple and classic. In the 10K unit, Grover’s product definitely met that description. The trailer was stout enough to do the job while including absolutely nothing nonfunctional. Two large plastic bins (rated to withstand the sun’s UV rays) housed the working guts of the system. The solar panels could be locked down flat for transport.
By the time we’d positioned the trailer where I wanted it, anchored it down to prevent flipping in high wind conditions, checked this and checked that, it was getting dark. The heaviest possible load, i.e. the air conditioner for Pam’s room, was test-run for an hour. That item could drain the battery bank completely if left to run without limit after the sun goes down.
But with the solar panels producing up to 960 watts in direct sunlight and the AC unit pulling 745, Pam should be able to cool her room for a few hours in the heat of the day with no problem.
Testing: Grover had the generator operational all day while he was driving over from New Mexico. As a result, the Trojan battery bank (410 amp hours of storage at 24 volts) arrived with a full charge. When we turned off the AC unit at 7:00 p.m., that bank still read 24.7 volts on the voltmeter. (The readout unit can be set up as a remote display inside the house–but I’ll do that later.)
Just now, at around 1:20 a.m., I took another reading. The idea is to find out how well the battery bank will hold up under our normal “night usage” which includes 2 fans in Pam’s room, TV usage ranging from 2 sets to zero, 1 or 2 lamps in (40 watt incandescent bulbs), my desktop computer, and a small printer.
The voltmeter display showed 24.4 volts.
Excellent! More than six hours of deep-night keyboarding plus a bit of Fox News and Jimmy Two Shoes (the cartoon series), and we’ve only lowered the battery bank charge by 0.3 volts!
It doesn’t get any better than this.
Rated 5 Stars, A+++++.
Update: Early autumn, 2013. We’ve now been living with the PowerGenX 10K solar generator for approximately 16 months. As in any relationships, there have been adjustments along the way. A few details:
1. Over time, three of the four outlets self-destructed. Grover had wisely built with GFCI (Ground Fault Circuit Interruptor) outlets to protect the system from any stray current that might go crawling around where it shouldn’t be crawling around. Unfortunately, we can get rough on equipment around here. There are plenty of close lightning strikes during the summer monsoon months, and my wife tends to blow up electronics–I believe her epileptic brain puts out an EMP (pulse) when she’s upset.
Those three outlets have been replaced with cheaper, more rugged, non-GFCI outlets. That has been working fine, and one more new outlet remains hanging on a wall in my office, waiting for the time that forth GFCI outlet needs to go. Not a problem; we simply had to downgrade to meet our onsite conditions.
2. In the autumn of 2012, the voltage rose (which it does in cooler weather)…and the total number of volts hitting the TriStar controller got too high. The controller started shutting itself off to save the system. A call to TriStar diagnosed the problem: Grover had wired all four solar panels in series, 4 panels x 37.5 volts = 150 volts, which quirkily enough happened to be the exact cutoff point built into the controller.
Grover and I spent some time on the phone with each other. I didn’t (and don’t) blame him for what amounted to a wiring error. Anybody, engineer or not, can overlook a simple thing like that. As long as he was willing to help me figure out how to fix it, I’d be happy–and he came through just fine.
First, he told me how to disconnect one of the four panels and bypass it entirely. This would be a temporary fix, giving us just 3/4 of the otherwise available solar charging capacity, but that was not a problem. It turned out that even three panels could easily top off the battery bank on any day with a reasonable amount of sunshine.
Then, he mailed over another solar cable. The idea was that I would eventually rewire the system in two strings of two panels each, producing a maximum incoming voltage to the controller of 75 volts.
I bought a combiner box to do just that…but haven’t hooked it up yet, partly from pure procrastination but partly because I’ve now got a better idea.
It turns out that there are two main types of controllers being used for solar systems today: MPPT and PWM. (Grover no doubt knew this, but I didn’t until I researched it on the Internet recently.)
Grover had built our system with an MPPT controller, which stands for Maximum Power Point Tracking and is designed to squeeze every possible watt of juice from the solar panels. He knew I was concerned about having enough power to handle the whole house, so that made total sense.
However, I’m now looking toward switching to a PWM controller. That stands for Pulse Width Modulation. It’s much, much less efficient than MPPT technology–but it’s also simpler, and its main attraction is its focus on extending battery life. The battery bank is the most expensive (and most often replaced) component in the system, it turns out we have more “panel power” than we really need after all, so….
That’s a long, hairy dog story, a wordy way of saying that although the PowerGenX 10K portable solar generator turned out to be “not quite perfect” as delivered, the only glitch that was due to the manufacturer’s error was the serial wiring of the panels. Every other imperfection was entirely my doing in the planning of the project. Grover used super heavy cabling (which is what you want), high end name brand components, the works.
This generator still rates a full FIVE STARS, by far the best bang for the buck we’ve found anywhere when it comes to portable solar generators