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Ready for Zombie Apocalypse!

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Lloyd

Well-Known Member
Supporting Member
Jan 12, 2011
6,437
2,383
San Luis Obispo, CA
Transitioning to Electric Vehicles has made me more aware that we are dependent upon the electric companies for reliable power. I decided to search for a used generator and install it on my home for backup power. I am now ready for Elon's Zombie Apocalypse! I thought everyone here would enjoy seeing some photos.

Found the generator I was looking for 30 KW Engineers Special in Los Angeles. It was previously used by Nextel as backup power for a remote cell site. This Generator is set up to produce either single phase or three phase with the flip of a switch. It was previously set up to monitor all parameters of the generator remotely from a cellular data link. It has a 120 gal tank which would run for some time if necessary. It burns about 1 gal per hour with a moderate load. It is powered by a 62 HP John Deer turbo diesel. I paid $7500 and it has 5000 hours on it.

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The seller told me that it weighed 6000 lbs, and when I got there it was 8200 lbs with 900 lbs of fuel on board! It was a little much for my 1/2 ton pickup. I melted my catalytic converter, started a small fire, but Cal Fire was going the opposite direction, saw it happen and put it out immediately. You may see a little smoke in the background.

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Well finally got it home, and in position with help from my friends at Johnboys Towing.

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I fabricated a connection point with Cam Loks to keep the generator portable.

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I dug about 300 feet of trench with Direct burial wire and control wires. I used 2/0 aluminum good for up to 190 amps as service entry.

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This terminated at my meter panel where there are 2 X 200 amp services.

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On the opposite side of the meter panel I installed 2 X 200 amp automatic transfer switches.

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These automatically start the generator in the event of grid loss, and once weekly for 20 minutes to exercise the generator.

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This was a fun project and everything went together seamlessly. When going on an exercise cycle, I dont even notice the transition in the home. Monitoring the voltage, the generator runs at only several volts less than the utility power.

This generator has no problems charging the Tesla even at the full 80 amps from the HPWC.

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That's a pretty reasonable price for that piece of equipment. 5000 hours though? Wonder if they ran the site on pure diesel for a while until the power company delivered service?
 
I knew this would be available some day. What did you use for your diversion load and controller?

Since I only expect to use this system in an 'emergent' situation I don't have those... they're not needed for operation. The primary... and really only benefit would be to allow for '3 stage charging'. Without a diversion load the Battery-Based inverter shoves all the energy not being consumed into the battery bank without regard to SOC. Once battery voltage reaches a pre-set level the Battery-Based inverter raises frequency to 60.5Hz... this causes the grid-tie inverter to trip.

I've considered buying one of the new 3.6kW 600vdc charge controllers that morningstar released recently but I'm having a hard time justifying the expense... This would serve the same function as the diversion controller (precise 3 stage charging) to prolong battery life, with less complexity and slightly more redundancy. I'm not too concerned about over-charging... my back-up batteries are flooded lead-acid and they're fairly resilient to overcharging.
 
$4 K for an inverter AND 15 kWh of storage? That's insanely cheap. Way better than Tesla's Powerwall. I'm going to have to look into this.

4.4kW AC coupled inverter $2159.20

I went CHEAP on the batteries since they're just standby... $83ea + ~$15 core fee at Costco. That's ~$800 for a full 48v bank ~10kWh/bank.
If your batteries will get more use... or you want a higher quality brand I would get Rolls Surrette S550s

Lithium Ion is definitely going to have the last laugh... but for the next ~3 years lead acid is still the cheapest standby source... if you don't plan on cycling more than once a month... I really like the power wall and if I was going to use a battery system on even a weekly basis it would be WAY better than this. The efficiency of a 48vdc PBSO4 system are TERRIBLE. ~90% charging * ~80% DC-DC * ~90% inverting = ~65%... the Powerwall is SIGNIFICANTLY more efficient since it's ~350vdc, DC-DC charging/discharging...

One 'trick' I discovered instead paying ~$4 per batter jumper is using 5/8" copper tubing cut to length... I've tested it to ~100 amps and the voltage drop is negligible.

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The best price/performance, in a year or two, will be a couple of powerwalls with the correct solar inverter. That will give ~8000 watts output. With the grid down, and a large solar array, a house and car should be manageable. Not "just like the grid", but manageable.
 
I knew this would be available some day. What did you use for your diversion load and controller?

If you use SMA Sunny Boy Solar PV inverters, SMA also makes the Sunny Island Inverter controller that is UL approved. The Sunny Islands will control a battery bank, throttle the PV inverters as needed, avoid shocking utility linemen, and even control a backup generator if the PV is not enough.

See SUNNY ISLAND 6.0H / 8.0H

I went a little excessive (retired engineer syndrome). The system is 24 kW Solar PV, 20 kW Sunny Island, and 150 kWh of lead acid batteries. I do have one 14-50 on the system that is turned on when the backup batteries are over 50% SoC. 40 Amp charging works fine with or without sun, but is better to use when the backup batteries are nearly full and there is good sun. My only problem is that system is too good; and I had to add an indication that I was off-grid. The power failed a couple of times, and I did not find out about it I tried something on a non-backed up circuit.
 
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