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Tesla Solar Mini Grid development-open source project.

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Hello, fellow Tesla Enthusiasts.

I am new to this forum. I hope this subject matter is appropriate. If not, please advise. I am delighted to have found a group that might be interested, and possibly provide feedback, on my project here in Erie, Michigan, USA.

I am developing what has been coined, the: “Tesla Solar Mini Grid” (TSMG). It consists of 7- Solar World, 280w, mono-crystalline panels, wired in series, producing 1960w/h at 220v DC input to inverter. I am in process of adding a second row of 7 panels, that will also be wired in series, bringing the system output voltage to 440v DC. I’m thinking this voltage is close to the Tesla battery voltage.

The purpose of the TSMG is to furnish supplementary power to a local Grocery store, that has a 50kw/h average daily load, but has a 80kw demand charge every month on the electric bill, @ $10/kw. I’m trying to design the TSMG to furnish that extra 30kw, for 15 minutes, surge power… but it’s really hard to do that when the Sun sets, of course.

Suddenly, the Tesla Power-Wall (TPW) appears on the market, and now there may be a way to integrate the two systems. However, things get a little foggy when trying to figure out the type of switch to use to interface with the grid, to supply the extra 30kw demand, without draining the TPW in a couple of hours.

The present Inverter configuration uses an SMA 3000TL-US-22 (the Sunny Boy). Its design input voltage rating is 125-600v DC, rated v = 400v DC nominal. Rated output is 3,050va at 240v nominal AC, single phase. This is the only inverter on the market, that I am aware of, that will allow the panels to come on line, when the grid is down, and there is sufficient sunlight, furnishing up to 1500w/h at 120v, 60hz, single phase, for small appliances (Secure Power Supply, SPS). I plan on adding a 120v to 240v step-up transformer, so I can run a well pump, if needed. I will also be installing several capacitors, to help out with power factor control.
Sorry, for the long winded introduction, but I could use some help, if anyone is interested.

My biggest question is: How do I manage power flow to/from grid, when a high demand, from refrigeration compressor starting, kicks in?
I will be documenting this open-source project at www.starlightpower.net I welcome any comments.