Thursday, April 28, 2011

Off grid expansion

Craigslist has been a blessing once again. I was able to secure another solar panel for much less than retail price.

This week's score was a BP Solar 12v/50w panel. It is in brand new condition.

I now need to re-work the mounting structure to accommodate this new panel, as it is a different size than my two Siemens panels. Once that has been done we will have a total of 136 watts of power.

So far this year, we've mowed the lawn twice, using an electric mower powered from the inverter. It has worked well, but towards the end of the job I could tell that we were getting pretty low on juice. I don't think that our batteries are in the best of condition, even though I have checked and maintained the fluid levels.

I am continuing to look around for some better storage batteries and will be patient until I do. It will have to be something local as shipping for deep cycle, or any automotive battery, is pretty expensive.

Do you have any recommendations for the best battery for the buck?


  1. My experience with solar power goes back to 1999. I built an extensive system. Used a big rack of Siemens panels to trickle charge a bank of purpose built deep cycle batteries. This was hooked into an inverter that kicked on a 5KW diesel generator when the batteries got low. I had grid power, so all this was in preparation for grid failure. Unfortunately, I found I could charge all day but the batteries had to be augmented by the generator anyway after an hour or two, if we ran any load other than just a few lights. Now I just use the generator when the power goes out. The batteries lasted three years, despite the fact that I tended them like infants. Rather than spend a fortune replacing them, I decided to dispense with solar power. Maybe now, ten years later, the technology is more up to speed.

  2. I think that another decade has certainly given the battery industry time to create better mousetraps. I'd say that the advances in portable devices has certainly led to much better li-ion batteries. I do remember when Ni-Cad's were all the rage, but they only seemed to last an hour or two.

    For marine batteries, 3 years is about the norm. The more expensive golf cart batteries might see a 5 to 7 year life, and some forklift batteries may even go 10 years, but eventually need to be replaced.

  3. Thomas Edison invented a Nickel-Iron battery in 1918 that lasts for decades at 100%, but since it doesn't have the high cranking amps needed for automobiles, his batteries lost out to the Lead-Acid batteries. His batteries were used in fork lifts, and some of those batteries are over 80 years old and still working. Here is a flyer for a modern version of the batteries. I'm not affiliated with the company, and have never bought from them, but they're made in China on older German equipment. Just another option, though I wish they were made in the US. - Jack

  4. hey I am selling 240 cells Thomas Edison batteries I am not sure where to list them Craigslist or Ebay ?? can anyone tell me n how do i advertise them to get bidders

  5. Thanks a lot Terry very good posting.
    I really don't know where this is going to end. Energy decision
    are such long term ones and there is prosperity of scope to get these wrong. diesel generator for sale.
    I think we will all have to invest in our own energy supplies as there is no guarantee that the current suppliers will be able to supply in 10 years time.

  6. if you still have these can you call me? Thanks 918-884 five one four five. John. Thanks.