Came to a fairly major decision yesterday and began to bring the pieces together. Technically, this is an addition to the Tanglewood Winter 2015 plan since I should have it done by May, but we'll see of course.
As long time readers know, I've wrestled with my solar batteries for a long time, nearly since I moved in. There are a bunch of reasons -- the original stack of Deka 8G8D Gels
was too small (only 1,350 Ah for the big, modern house I was building), then it turned out that some of the settings were wrong (never never
equalize a Gel battery!), then I wrestled with partial charge and discharge issues. Eventually it became apparent that they were just plain dying, and this came to a head last November when I discovered only three of them actually working
. I quickly put into place 8 excellent quality Interstate Battery 420Ah lead-acids
to get me through the winter while I considered my options.
I have decided I'm sick to death of dealing with batteries that are almost-but-not-quite-enough to supply Tanglewood through a cloudy day.
I have decided I'm sick to death of constantly feeding my generator(s), plus the added annoyance of having them blow up at the worst times (amazingly I've had four generators in the last five years!).
I have decided it's time to do something drastic. In keeping with prior lessons I've learned over the past few years, I have never regretted Gross Overkill in solving a problem. And it's time to to apply this lesson once more.
My plan going forward is two-fold:
- First, I am buying a new Outback FLEXmax-80 charge controller. There are two reasons for this. The first is that my current number of panels (36) is actually slightly more amperage than the two Outback 80s that I already have can handle. Granted this is a theoretical maximum when it's a cold, bright, sunny day, but we have those here more often than not. Right now I've got six panels actually turned off as a safety precaution; I'd like to regain the benefit of their power generation.
- Secondly, after much research I have decided to purchase a 2,288 Ah battery rack, the Outback 2700 RE rack-mounted system. These are AGM batteries (Absorbed Glass Mat) that won't freeze and which are very tolerant of deep discharge if that should happen. By my estimates this should once and for all solve my energy issues, giving me tons of excess capacity to weather three or more days of dark, overcast, just-ain't-gonna-make-much-power days. This means I won't use my generator as much, I won't have to buy as much propane, and I won't have to deal with managing power on the overcast days.
Also, having the extra charge controller means I will have a charging capacity for the larger battery bank. Theoretically three controllers can put 240 Ah into the battery rack, about 10% of the total capacity. This is an excellent spot to be for charging, and should have me hitting Float on a bright and sunny day by noon and gives me the whole afternoon if the days are somewhat less sunny than one might hope.
The FLEXmax can be installed (and in fact should be) before I get the batteries, and besides it's off-the-shelf--the batteries will have to be built. I placed the order for it today and it should be here in a few days, at which point Solar LeRoy and I will do some quality rewiring work to put 12 solar panels on each charge controller and get those deactivated ones turned back on.
The batteries I'll order a bit closer to May, which is when I'd like to do the installation. By then we should finally (please Odin!) be done with all of the snow and the cold and the muck, and I'll have cleaned up much of the mess that's around the Shed site (the old batteries and pieces of the old shed).
This is a big step but one I'm moving forward with eagerly.
Much to do before the end of May!
Steven in Colorado
My Construction Website
Login to Reply