[RE-wrenches] Mobile Solar power Center

[Michael Welch]

Hi Peter. I have been involved with powering many community events with both off-grid and guerrilla intertie systems.

For most events, the PV array did not add much energy, at least compared to the size of the load. The array is mostly feel-good, but with portable units can be used to recharge the batteries before and after an event.

For battery-based events, you will often find yourself unable to help them, do to a lack of energy and power. My recommendations: Put as many batteries in a double-axle trailer as you can afford and it can carry. The more batteries, the more and larger events you can help out. Same way with the inverters. I am thinking that 1 KW of inverter power won't help much with a lot of community events. If I was going to build one of these things, my tendency would be to go with at least 4 KW of inverter power. 

I would make the inverters grid-tie because the unit is going to sit around a lot with nothing else to do, you might as well feed that otherwise wasted energy back into the grid at your shop. 

My own fantasy trailer would have a double stack of OutBack GVFX3648s, and about 2,000 Ahr of industrial flooded batteries to back them up. That's about 50 KWH at 50% DOD, which would probably be enough to provide stand-alone energy to small sound systems with  a little stage lighting.

A bunch of solar bozos, some of who are on this list, used to help power the Pignic at the Hog Farm near Laytonville, CA. We would always put up a temporary array with lots of AEE-provided modules, and there were usually two inverter systems, a big rack of Exeltechs and an SW power panel, but the real key to the system was battery power. Joseph Marino, DC Power Systems, would show up with a large flatbed truck full of big, charged batteries.

So you have to decide which is more important, "show" or "go." Of course, system cost is always a factor.


Peter Parrish wrote at 08:49 AM 1/19/2009:
 
>We are designing a "Mobile Solar Power Center" to power Eco-Events and the
>like in Southern California. We will have 1,600 Wp of solar panels, 6 kWh of
>24 V AGM battery backup and a 1kW / 120 VAC inverter. I am designing the
>system from scratch, and I wondered if anyone else out there has put
>together a similar system and was inclined to share notes. When I'm finished
>I'd be glad to do the same.
>
>One stumbling block I have right now, is to find a DC rated 70A in-line
>fuse, to put between the battery bank and the input to the inverter. 70A may
>seem an odd value, but it is the best choice for the surge rating of the
>inverter I'll be using (Xantrex Prosine 1000). Does anyone have a source for
>DC-rated in-line fuses? 
>
>Thanks in advance, -Peter
>
>Peter T. Parrish, President
>California Solar Engineering, Inc.
>820 Cynthia Ave., Los Angeles, CA 90065
>Ph 323-258-8883, Mobile 323-839-6108, Fax 323-258-8885
>CA Lic. 854779, NABCEP Cert. 031806-26
>peter.parrish at calsolareng.com 
>
>
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