December 7, 2015
A Recycling Story
This update is not about cruising – it’s a story about our house batteries and an interesting project where they found new life.
Some of you may recall that back in May we replaced our house battery bank (see the video here). These are the batteries that power the boat when we are at anchor, away from shore power, and not running our generator. We have 16 Lifeline AGM GPL-8DL batteries which provide 2040 amp hours of power when charged, enough to power the boat for about 18 hours between charges. However, our batteries were five years old, not lasting as long as they used to and taking longer to charge. So we decided to replace them.
Each battery weighs 156 pounds and each can be sold for re-cycling at about $30 per battery. But these batteries weren’t completely used up – they still had some life in them. So I decided to see if we could find a better use than sending them straight to the re-cycle facility. This ended up taking some time, and in the end I got only marginally more for the batteries than I would have by sending them to re-cycle, but I found good uses for the batteries and met some interesting folks in the process.
To start, I took several batteries to the local Intersate Battery store where I had them tested to determine their Cold Cranking Amps (CCA). They all tested out just fine – not like new, but still plenty of power. So this was some confirmation that the batteries should have some life left in them. Then I posted an ad on Craigslist and got several responses from people who were interested. In the end, two people purchased our used batteries. First was Billy, who has several boats he uses to take his grandchildren out and needed some engine start batteries. He wanted three of them. He couldn’t afford to pay much and lived 2 hours south of Beaufort. But I had a trip planned to Southport and was going to pass right by where he lived. So I was able to deliver them to him on the way!
Then there was Luis. He lived in Charlotte, a four-hour drive from where we were in Beaufort, NC. Luis has been working on a project to install a solar farm at his home. He needed a large battery bank that would provide power when the sun was down, but could not afford the cost of these batteries new. He was willing to drive four hours each way to pick up eight of them.
He arrived with a small SUV and we loaded the eight batteries on board. We could hear the SUV groan, but it made it back to Charlotte where Luis installed and tested them.
I still had five batteries left and Luis called back a few days later, saying he would like to drive back to pick up 4 more! They turned out to be perfect for his project. So back he came and he took the remaining five – they need to be installed in groups of 4, but he took the additional one as a backup.
I asked Luis to provide some more details of his solar project and here’s what he said:
There are 20 Unisolar PVL-136 flexible solar panels in two sets (10 to the left and 10 to the right) connected in pairs to make them 48 volts 4.13 amps. Each side is independent and produces 72volts at about 20 amps. The two circuits go to a 60amp dual pole disconnect switch next to the panels and from there to the garage using 6 AWG PV wires.
In the garage the two lines go to two 30 amp DC breakers and from there to two 1200 watt Power Jack grid tie solar inverters; the output of these inverters is then combined and goes outside to a main AC service disconnect switch and back in to the house main breaker box.
The inverters pump around 2kwatts per hour into the grid and this covers for just about everything we use during the day including the Trace Voyager 2500 watts marine inverter with 3 stage 120 amp battery charger that charges the very nice GPL-8DL batteries courtesy of my friends at Shear madness.
With the help of an external automatic relay, when there is sun light the inverter goes into charge mode when the sun goes down. It assumes that there is no power and it takes over the load on the house till sun is up again.
As of Dec 1, the batteries are working great! They are now working 24/7 and running 70% of the house and being charged by solar power. They hardly go to 30% discharge over night and reach full charge by 2 or 3 in the afternoon. I’m extremely happy with them!
So there you have it, a modern recycling saga!