Off Grid Power - Lessons Learned During a Recent Power Failure

Readers of my blog will remember the Battery Cart posts dealing with an off-grid power supply of my own design and construction. A few weeks ago, we had a windstorm which knocked out the mains power in my area for several hours. During that time, I was able to test the capabilities of my power supply. To follow are findings and lessons learned:

1) The Battery Cart worked as intended - maintaining some lights, operating radio and computer gear, and keeping my Internet modem energized.

2) My Internet Service Provider does NOT provide emergency power for its network. While my battery system performed admirably in keeping the equipment on MY END operating, I had no Internet service through my ISP. I had to rely on a "wireless hotspot" cellular modem to use the Internet. It was through the cell modem I was able to get online to learn of how widespread the outage actually was.

3) I have ANOTHER pair of batteries in the basement to power the sump pump during an outage. And while the inverter I had SUPPOSEDLY could in theory run the sump pump, it was NOT able to start the sump pump in reality. I had NOT actually tested this before the power failure because I hadn't had the inverter that long. Note to self: GET an inverter that WILL run the sump pump - or risk having a flooded basement during a REAL emergency. I purchased a new, heavier duty inverter which came in the mail a few days ago. It needs to be tested ASAP.

4) "Op-Sec", or operations security. My next door neighbor came over and asked me if I knew what happened with the power - AND how it was I still had power. From outside, as it was getting toward dusk, he saw my ONE work light shining through the living room blinds. Silently, I pointed to the green battery cart sitting next to my work table. He replied "Oh my God, I forgot you had that big battery!" The point of this is that others WILL notice if you are running lights, or your TV, and WILL investigate to see how you are lit up when the other houses are dark. This could be a serious security breach during a prolonged crisis. Note to self: Have some tarps, thick sheets, blankets, whatever as "black-out drapes" if you are going to use lighting inside during early morning/evening or nighttime hours. Likewise, keeping the ham/shortwave radio or any music turned down would be a wise suggestion - don't attract unwanted attention to yourself by running your stereo loud enough for passersby or neighbors to hear.

5) "IP Phones". I already knew this, but if you have an "internet phone" such as provided through "AT&T U-verse" or Time Warner's Cable voice service, you will very likely lose your phone service during a power failure for the same reason I lost my regular Internet service - see point #2 above. These new "IP Phone systems" are NOT like the old POTS [Plain Ol' Telephone Service] lines of old that DID stay up for a time during power outages. Having a cell phone as a backup, even if you normally use a wired "house phone", is important. My elderly mom learned this the hard way when SHE lost her power and the UPS that ran the "AT&T U-Verse box" failed after 30 minutes. I don't know whether or not this has changed from a year ago, but when my mom got her IP Phone system, AT&T did NOT even offer a backup battery in their units!!

6) TEST your equipment REGULARLY! I can't stress this enough. Exercising your equipment regularly will familiarize you with its use, its strengths and weaknesses, and also will quite likely reveal maintenance issues BEFORE they become a show-stopper during "the real deal".

Anyway, I hope these pointers help someone.

Solar Power Plus Off-Grid Battery System: Putting It All Together

Readers familiar with my Off-Grid Mobile Battery cart will remember my writing about my plans to use solar panels to recharge the batteries. Reference Off-Grid Mobile Power Supply and Mobile Battery Cart Update for full background information. Over the past few months I have obtained a pair of brand new 100 watt solar panels from a supplier on eBay. I recently ordered the second panel and got it in the mail this week. I took advantage of the sunny weather and a breather from work today to test the panel "live" with the battery cart.

These 100 Watt panels each come with a pair of 10-15 foot long 14 mm cables and a charge controller. That is NOT a bad deal for $140 apiece!! Even ignoring the cost of the cables and controller, that comes to $1.40 per watt. Additional panels can be purchased without the controller for closer to $125. That said, any solar power system needs a charge controller to ensure the batteries aren't overcharged during full sun.

I figured I'd need about 300 - 400 Watts worth of solar panel capacity to really handle these 220 ampere hour batteries. As of now I have a pair of 100 Watt solar panels, though I'm just testing the one I got this week.

To run a quick test, I temporarily connected the whole mess up to the battery cart with some alligator clips, then arranged the panel on my front porch with the cables running through the front doorway back into my living room. I believe the charge controller may have issues, as it was only allowing about 2.5 amperes through even with a heavy load connected to the battery and a terminal voltage of 12.58 volts. I disconnected the charge controller and just connected the panel straight and got plenty of current, as the meters in the photo reveal. The orange meter is reading the current in amperes; the gray one is reading the voltage. At one point I did see the rated 5 amps these panels produce. Clearly, I need to address the charge controller issue, because at 4+ amps for ONE panel with a battery voltage of 15 volts, I'd quickly cook these batteries if I ran without one for long!

Stay tuned for future testing of the system with both panels : )

Mobile Battery Cart - Update

Those of you who have read my June 2015 post about the mobile battery cart will remember the Deka marine battery and the unpainted plywood lid. Since then I have painted the lid to match the rest of the unit and have replaced the Deka battery with two new 6 volt/220 ampere-hour golf cart batteries, purchased from the battery company I work for part-time. The batteries are both contained in ABS battery boxes so they are out of sight and any leakage that might occur will be contained. Having the batteries NOT readily visible is important, lest my landlord or, in the event of some emergency - firemen or EMTs, see them and get upset. Given the way this unit is constructed, it looks clean, organized and purposeful. One would NOT walk up to this and say "why do you have car batteries in your house?" Yes, it's clearly some sort of electrical device, BUT it's NOT scary looking.

Note that since the golf cart type batteries are taller than a marine or car type battery, they will not fit inside the standard ABS battery boxes available at big-box stores like Wal-Mart or at auto parts places - you'll probably need to get them at a battery company as I did. Mine cost me between $7 and $8 apiece. The batteries - made by USA battery - will run between $130-$170 apiece, typically. USA battery uses really hokey "quick release" type battery caps that inevitably leak; since I bought my batteries at a battery shop I was able to get GOOD LEGITIMATE screw-type retrofit battery caps at nominal cost. They're well worth the investment.

This system can provide about 2400 watt-hours of electrical storage - PLENTY for operating lights, amateur and shortwave radios, etc. in an emergency. Given about 300 watts of solar panel capacity, it could provide sustainable "off grid" operation.