andy,
sounds like some project building that tracker-hope you called for a pour with all that concrete..i once over estimated my ability to hand mix and it nearly did me in.
Oh yeah, it was definitely a concrete truck day....actually it was also a concrete PUMP truck day.....since each of those took a bit over 2yds each and are located up on a hill above the house.....but I combined it with a pumped pour for a new root cellar roof ( 8x12 x 6" thick ) and some retainer wall block fill, so he pumped 10yds that day.
cheers on welding those monsters up, learning that skill (welding) has moved up on my list of "things to do" and am looking for an easy wire feed mig to have around the shack.
i'm currently working on an axial flux build (based on hugh piggots three phase design) and enjoy trying to do a project %100 on my own.
Yeah, I'm a certified "farm welder".....as long as it doesn't leave the farm, it might hold....ahahahaaaa....
Nah, I do fair at it, though if it's something critical that has to hold pressure, I go get a buddy that really knows how to weld. I have a Miller "Bobcat" stick welder.....engine driven 16hp 200amp model that also doubles as a backup generator ( 8kw ), then I also bought a Miller MIG wire welder a few years ago....that one makes even a 'farm welder' look like they know what they are doing !
that sure is an impressive amount of pv you are running. are both arrays running with mx60's? i'm sure you have your reasons for not going with a grid tie. there are some locations that give you a feed in credit based on "avoided costs" and them sell it back to you at standard rate. you must be close to being self sufficient with your power needs with that set up, and after ponying up for pv one sure learns to respect the amount of power we use.
MX-60 on one array....FX-60 ( what replaced the MX ) on the other.....I expanded once already and the MX was no longer available.
Don't know how I left you with the impression I'm off grid, because this is a grid tie system with battery backup....I have 8 --L-16's in backup....and plan to add 8 more, for a total of 1600 amp/hr....the first panels I installed were off grid for a bit while I experimented some....but then I got serious about the whole thing seeing what they would do.....
We DO have a nifty credit here.....TVA pays 15 cents/KwHr for all wind/solar up to 50kw sized system, then after it goes thru the buyback meter, we get to use that hour we produced for free IF I'm consuming electricity at the time ( which with a fridge and 3 freezers, something is always running here ), so that avoids buying that hour at 9.3cents to boot....pretty sweet deal I thought. My goal is to get my system up to where it replaces about 1/2 what we actually use ( about 900kw/hr/month year round average )but replace ALL our bill due to the way the money works out. Then I'll quit and move on to another project.
andy, i'm curious if you have had any after thoughts on making those trackers with a fixed 37* angle? (vs manually adjustable).
My understanding with single axis trackers is you get about 30% more out of them ( and that seems to be holding true from what I see, playing with mine leaving one fixed in the "noon" position and letting the other one track ), but only gain 8% more on the other axis. Since this was a "home built" deal, I decided to weld the up-down axis good and solid ( not knowing how wind would affect things.....getting a lot of "sail" area up there now )and just to make life simple. Probably if I could come up with a good, solid, manual design to crank it up-down, I might...but I'm happy with this. I have less than a 1000 bucks in each tracker, and that blows away the prices I see for active trackers this size...and I suspect my design is a LOT more stout....I tend to way overbuild stuff.
BTW, we're coming up on our first "MEGA watt/hour".....1,000 KwHrs.....should happen tomorrow evening or the next morning based on these new panels I got up today......we went "online" end of December 08 for buyback purposes.....it's been doing 12-13kw/hrs a day lately, and now we're upping that by 6 panels ( 50% ), so we should be cranking out 18 or so per sunny day....the fans never shut off in the inverters on a days like this...ahahahaaaa.....but that's ok....that waste heat isn't wasted....it's going into my greenhouse (solar gear room is on one end of it )......the tomatoes love it.
I'm not a big fan of waste.........especially when I paid so much to get it.....ahahahaaaaa
andy
