Going off Grid
Boat living, tiny house living, van living, tent living, cave living. . ..one of the advantages of virtually ANY living other than the standard suburban home is that your small spaces and tiny carbon and energy footprint means you can have an unprecedented amount of freedom from utilities, services, and their associated bills. One of our objectives in this livaboard enterprise has always been to get as far off that dependence as was possible.
|The Floating Empire's original 200W of solar was fine for electronics and internal lights. . .that's about it.|
Our original shantyboat “The Floating Empire” went a long way in that direction. We were able to filter and pump our own water, and our scant 200W solar panels provided enough power for our electronics and interior lighting, but, sadly, not for refrigeration or travel. One of the driving forces behind getting our new vessel “Tesla's Revenge” was to take care of this.
So in our right minds and everything and after large amounts of caffeine, we've begun the process of getting fully off grid, with new components and a new battery layout, with an eye to producing and being able to store enough power to both live and travel unconnected from shore power.
|Here's the hardtop, caulked and painted and ready for the membrane covering. It EXACTLY fits the four new panels. . . .I didn't ask where I as gonna stand to put them on, now did I?|
Every solar system is made of two major parts, both of which are limiting factors to what you can do. The first is, of course, the solar panels. Modern panels produce a LOT more than their predecessors, and the prices have plummeted. Our ultimate goal is to have 1300 watts of energy coming in, the limitation being more one of the surface area that we have on which to MOUNT the beasts than anything else. The second part is your storage, how much of that energy can you put away when the sun ISN'T out, and how rapidly can you draw off that energy when you need it. This is somewhat complicated by the fact that our new motor system will run at 48 volts, which means both the solar panels (normally 24V apiece) and the batteries (12V, grouped in series to make 48V) must be wired to match that voltage, and anything like, say, an inverter to produce 110V AC for appliance use must be able to take 48V on the DC side
After a couple of days of the knuckle busting job of rewiring our 8 deep cycle batteries in two series sets of four (48V, remember?) and dragging wire and installing our new 48V true sinewave inverter and the MPPT controller to regulate the power going from the solar panels to the batteries, we embarked on the perilous task of mounting the first two of our four solar panels on the hardtop. Actually, we wanted to do it the day before, but there were 16kt winds, and I figured I'd wind up somewhere over White Marsh hanging from a flying solar panel. Stylish, yes, but the landings can be messy.
One great place to acquire solar panels (if you're looking for large and high output) is solar installers. They buy the things by the palletload, and after they finish an installation, they'll often sell off the remaining few panels at cost or nearly so. We dealt with the VERY nice folks at Ameresco Solar in Chase and managed to acquire a couple of 325 watt, 24 volt panels for a very reasonable price. Great. Okay.
|Finding a place to mount the inverter and the MPPT solar controller was a bit of a challenge as well. We opted for beneath the companionway step.|
So now all I have to do is managed to install two 6 ½ by 3 ½ foot, forty pound solar panels on the top of a moving vessel. We are VERY fortunate to have some lovely slipmates who came over to help us get them on top of the wheelhouse, which made life a lot easier. Of course, though I figured my spaces PERFECTLY for the installation, I forgot to ask one simple question: Where the hell do I stand to screw these in? The resultant, somewhat comedic installation routine resembled someone playing a game of “Twister” over a bed of black, hot, potentially shatterable glass with a cordless drill in one hand. This was one of those moments when extra limbs might have come in handy. Certainly, my wife's suggestion that I put on taller shoes (no kidding, it worked) made it possible by about 2/3 rds of an inch. Regardless, we got it done, clipped together the wires, and low and behold, we were powered up and off grid. . . .
|Two Down, Two to Go|
. . . .sorta. . .
It's been four years since we launched The Floating Empire, and that's about the lifespan of the original bank of deep cycle batteries. Frankly, they're getting a bit elderly and are no longer up to the task. We can produce plenty of power now, but can't store enough of it to reliably make it through all evenings and cloudy days (a problem also faced by municipalities and utilities working with renewables. Tesla's working on it.). So I'm spending my days at the moment shopping for another block of 100AH batteries to replace our old bank. For the moment, though, we have just dramatically reduced any power consumption we had (which wasn't much). The current system can provide power for all our internal lighting, electronic gear, refrigeration, fans, and assorted small appliances without being plugged into shore. As soon as the new battery bank goes in, We'll be completely disconnected. Then we put in our 4.7KW drive motor and other goodies, and another two panels. . .
Yay, off grid.
Where am I STANDING to put in the last two panels? I have no freaking Idea.