Hello from the Catskills of NY

Hello everyone,
This is my first post so I'll give you a little background:
I'm a retired electronic engineer, I still do some writing and magazine articles but I'm winding most of that down now as I want to devote more time to my solar projects.

At this point I have a 6.4Kw intertie from a grant through my rural electric coop that I installed last August. Before that I installed an off grid system with 8 Solarworld panels, two Outback VFX4836 inverters and an MX60 mppt.

I just purchased 12 Sharp "B" grade 240W panels on Ebay and am in the process of building tracking inverters for them and the 8 previous SW panels which are now in wood racks.

I'm MIG welding mild steel CRS steel tubes (or 6061 tubes depending on price) for the tracking frame but I haven't settled on linear actuators as of yet.
For the tracking electronics I'm going to program microcontrollers (I use Atmel's 8 bit uC's) with a twist. Instead of using LED's or CDS cells I'm going to program the controllers to follow the sun using a time algorithm that I will be able to control from my house, especially when I need to protect the panels in high wind or storms.

I was wondering if anyone has found a good linear actuator for a reasonable price? I haven't finalized the frame layout completely yet but I'm thinking about 18" of travel forthe actuators. I'll be making 5 structures with four panels on a structure using 4" sked 80 pipe in 18 to 24" sonotubes.

Rob

[diyEthic]

Welcome, Rob! I've been researching inverters and I like the Outback grid-intertied models for their ability to function off grid during grid failure. I haven't heard of any other grid-tied inverter with that capability. I don't have a PV system yet, but seriously considering it now with my utility offering a feed-in tariff of $0.30/kWh. Selling Your Clean Energy - NIPSCO

Originally Posted by diyEthic

Welcome, Rob! I've been researching inverters and I like the Outback grid-intertied models for their ability to function off grid during grid failure. I haven't heard of any other grid-tied inverter with that capability. I don't have a PV system yet, but seriously considering it now with my utility offering a feed-in tariff of $0.30/kWh.

DiyEthic,
When I installed my off grid system I had no idea I would be offered the intertie grant, so it was a nice bonus. Also the fact that I did all the work myself meant that I broke even at the $3.00 a watt they gave me. I think I was the first person to do their own intertie, I had an installer come in but he wanted $7.50 a watt. The hardest part was the frame racking on the roof. I did my own drawings and layout diagrams and I had to put the money up front for all the components, so there was a small lag to payback.
It's a great feature to have one inverter do both on and off grid and the Outback components I put in have worked flawlessly over the years.
The intertie means I don't have an electric bill every month, in fact I come out slightly ahead so I'm better than net zero.

Rob

[Daox]

Welcome to the site Rob.

It sounds like a cool project you got going on. We'd love to hear more if you don't mind sharing.

Originally Posted by Daox

Welcome to the site Rob.

It sounds like a cool project you got going on. We'd love to hear more if you don't mind sharing.

Yes, Sharing is why I'm here, as soon as things get rolling I'll give out the circuits, frame designs, etc. to help everyone along and also learn more myself from feedback so we all benefit.
I'm just compiling the metal requirements now and hope to have the frames welded up by the end of the month (July 2012) and also the holes started for the poles.
I have received the 12 "B" sharp 240 watt panels and have examined the first few. I can see some small flaws but nothing that concerns me. At 90 cents a watt these are a real steal. Now that there are tariffs on the Chinese panels I think the US manufacturers will have a better go of it.

When I built our house back in '92 I had envisioned all this taking place, every year I get a little more done. The time I took to lay out the house so as to maximize the sun and air currents has sure paid off!

Rob

Thanks for the welcome!
Here's a little update. I now have the panels and all the materials to build the frames. All the frame drawings are done (TurboCad) and next week I hope to get the poles in the ground (Photos to follow) and start welding up and plasma cutting the frame parts. I still have not settled on linear actuators for the tracking yet.
My Steel supplier can cut the two frame parts that I'm doing myself with plasma so when the design is done I expect those of you who don't have the equipment, or friends with it, will be able to have it done for you.

Best to all,
Rob

ps: Here's the framework showing the 6 Sharp panels mounted (just the Sharp frames with the framework showing through.)