Green-Trust.Org

Our new Photo Voltaic Solar Panels arrived this week while we were in Ft. Benning, Georgia. We were there attending our Son’s graduation from Infantry Training.

The six Panels are 195 watt Sanyo Hybrid panels. These panels have a amorphous layer over top the mono crystalline layer, and work well in cloudy and overcast weather as well as bright sunny weather. It was in the high 20’s last night, and the sun is low on the horizon, so a 1200 watt boost to our existing 550 watts will be appreciated. This will greatly reduce our propane usage and generator run times, and keep our house batteries fully charged for longer periods of time. I’ll be posting pictures and desciptions as we install them, and will be updating our DIY Solar Power Installation ebook at http://www.green-trust.org/ebooks/.

We use a multifunction display from Outback called a Mate to monitor the operation of our charge controller, our inverter, and our battery bank. We have another shunt coming in so that we can monitor the wind turbine and solar independently. But what about logging and historical performance. It would be handy to be able to compare monthly and seasonal performance. Our Mate has a serial port on the side for connecting to a computer, so we are evaluating 2 software packages that will allow us to track and record the complete operations of our system.

The first is WinVerter-Monitor OB from http://www.righthandeng.com, and the other is WattPlot from http://wattplot.com/index.htm. We will let you know about the strenghts and weaknesses of both.

One of the critical chores in maintaining your off grid battery system is making sure the water levels are kept up. This prevents the plates from being exposed, and ruining a pack before it’s time. Some folks have physical difficulties, or plain forget to water, so we are introducing an automatic watering system that will add a bit of water everytime the batteries hit 100% state of charge. A 5 gallon resorvoir means that it will be months before you have to refill the tank, and no spills means no corrosion. All gases are collected and vented to the outdoors through a tube, so no indoor venting issues. The system is controlled by the relay contacts on the Outback FLEXnet DC, but a Xantrex system could be used as well. A 24 cell system (8 batteries x 3 cells per battery) will sell for about $500, and requires programmable relay contacts (Outback FLEXnet DC or equivalent).

The Quest for maximum battery life continues

A quick recap. The battery bank consists of 8 L-16’s, which are a 6v, 420ah battery, in two parallel 4 in series strings. This gives me 24v @ 840ah.

After cross-tying (massively paralleling) my battery bank, by connecting the positive posts across parallel banks, it was time for more drastic measures.

I installed a second hand BattEQ that originally came from http://www.abrahamsolar.com, but it wasn’t functional. One phone call, and 4 days later, a new one from http://www.smartsparkenergy.com arrived, and is now installed and functional. The BattEQ equalizes the charge and discharge to each battery in the string, and the cross tie cables distribute that functionality to the second string.

The next item on the agenda was a pulse desulphater, from http://www.pulsetech.net. The PowerPulse extends battery life by minimizing the size of the lead sulfate crystals. Again, because of the cross-tie cables, the effect is distributed across both strings. Installed and functional.

The next item I will evaluate is an automatic watering/degassing system, to prevent spills and corrosion, and prevent water loss. These steps should ensure I get maximum life from my battery bank.

By Mick Abraham

Solar power has been romanticized as a “green technology”, but truly in-dependent power also includes lots of “black technology”. An off-grid energy system may have clean non-polluting solar modules smiling at the sun, but it also includes heavy chemical batteries containing toxic substances like lead and sulfuric acid. Batteries are the dark industrial underbelly of off-grid renewable energy systems.

I’ve had a love/hate relationship with deep cycle batteries ever since buying my first one in 1984. Chemical batteries will remain essential to in-dependent energy for many years to come, but they also represent the number one problem area. Performance gradually degrades in ways that are barely noticeable at first, but the pack eventually reaches an “avalanche point” where the battery capacity falls off a cliff. This causes a crisis for the system owner which requires emergency money transfusions to their battery vendor.

Batteries are so problematic that those who rely on them can get discouraged. I’ve become acquainted with many “off gridders” as customers who later developed into friends, so I know a bit about their frustrations. Many have reached the point of selling their homes, bringing in costly line extensions from the grid, and taking other drastic measures. To me, each of these events represented a failure for myself, for the off-grid energy industry, and for its technology. Watching my friends and customers endure their battery disappointments, I gradually developed a personal quest to learn more about batteries and to look for ways to reduce these problems. My quest has now been under way for more than ten years, and it has changed my alternate energy business more than once.

In 1997 I introduced the PowerPulse® electronic sulfation dissolver to the alternate energy world, and I’ve shipped over 7,000 of those units since that time. Since independent power systems sometimes can’t recharge their batteries promptly, lead sulfate compounds can develop a covalent bond to the battery plates which cannot be reversed with normal recharge methods. The sulfate busters use a well understood means to resonate and dissolve the crystal form of lead sulfate.

PowerPulse (and the competing clones which soon followed) is now a common battery enhancement, but battery longevity has continued to disappoint. Even my PowerPulse customers still come up against battery surprises. It’s also not easy to confirm what the pulse device is doing or if it’s still working. I’m a believer but others have attacked this product category as “snake oil”.

In 2005, I began testing a new battery enhancement device which may prove more significant than the sulfate dissolver. This is an automatic battery balancer called BattEQ™. The product is based on research work at the University of Illinois. SmartSpark® Energy Systems, Inc. has licensed this and other patents, and www.abrahamsolar.com serves as a distributor & factory rep for Smart Spark.

SSES builds several different versions of their equalizer. The first one that I rolled out is optimized for 6-volt batteries, such as the popular “L-16 floor scrubber” or “T-105 golf cart” batteries. Other equalizers balance to the 12 volt increment for different type battery banks.

BattEQ rapidly switches a bank of energy storing capacitors from one increment of the battery string to the next. When the capacitors encounter a segment which exhibits voltage above the average, a bit of energy is absorbed. When the caps encounter a segment which is below the average voltage, they dump their stored energy. The result is a “flywheel effect”; each segment tracks the others with nearly identical voltage—with important effects on battery health and performance.

Alpha Telecomm has also licensed the same “flying capacitor” technology from the university; search www.alpha.com for the AlphaGuard™. In some ways, AlphaGuard is more “civilized” than BattEQ, but the balancer bandwidth with AlphaGuard is too low for house sized battery banks. BattEQ pumps more energy per dollar than any other balancer that I’ve seen.

Voltmeter tests are an easy way to confirm equalizer function; if a clamp style DC ammeter is available, one can clip around each balancer lead to read the energy throughput. The amperage readings are typically highest when the balancer is first installed; even on brand new batteries off the same shipping pallet, I never fail to observe a few amps of energy transfer.

Combining all my various prior efforts, my gleam in the eye is pack level sulfate dissolving (easy & relatively cheap), combined with balance at the level of individual two volt cells. The last part of this is much more of a challenge, so my next step is to just try for cell level information.

I’ve now got the ball rolling on a special version of the PakTrakr, to capture the voltage of each individual cell in a battery string (this assumes that one has access to the individual cell terminals, of course). www.paktrakr.com shows their standard offering (which I can also supply for battery users who have 6 volt or 12 volt monoblocs). I plan to post a flyer on the two volt version on my Top Floor before long. The Paktrakr products should particularly appeal to battery professionals who want a simple way to highlight battery balance issues for their customers.

The elephant in the room is this: since there is no BattEQ for individual two volt cells, what actions can we take if PakTrakr points up a single weak cell? I’ve got varying ideas in mind…of varying quality. As mentioned above, this won’t be easy but I do think it is worth working on and the next thing to do is get cell level data.

I extend my thanks to green-trust.org for publishing this article, and I hope to see fewer battery problems down the road. Charge!

Contact Information:

Mick Abraham, Proprietor

Voice: 800-222-7242 or 970-731-4675
Email: mick@abrahamsolar.com

Fax: 970-731-3292
Web: www.abrahamsolar.com
Skype username: abrahamsolar
Abraham Solar Equipment
124 Creekside Place
Pagosa Springs, CO 81147

In larger battery banks, where you have multiple series - parallel strings of batteries, you run the risk of some batteries getting more “used” than others, and this degrades your pack performance. A simple way to reduce this effect is to cross-tie your batteries. This is a rarely used but important method of getting extreme life out of your expensive batteries. Here is an example:

cross-tied-battery-bank

The dotted lines are the cross tie cables. It’s also important to make sure your cables are heavy enough, that you are not losing power as heat through resistance. If you have caps on your batteries, not maintenance free, check the water levels once a month and top them off during charging. Do not overflow. Next we will discuss pulse desulfators as another method of extending the life of your batteries. Stay tuned.

A reader on our 12v group brought up this topic, and it started the idea engine. There were a few models available in the past, of lawn and garden tractors, that used electric motors instead of fuel driven engines. Quieter, easier on the environment and your lungs, and arguably, on your wallet, it’s apparent that they are attempting a comeback. Appropriate on a off-grid homestead like ours, we are researching the availability, and possibility of converting our Sears mower to electric. See the following resources:

http://www.electrictractor.com

http://electriclawntractor.com

http://www.modernelectrictractors.com/

Please let me know if you find more of these units available or even DIY conversions.

Convert your gasoline generator to clean burning propane. We document the steps, and it’s a easy 45 minute process. See http://www.green-trust.org/ebooks/ for details

Our guide to installing your own power system is finished, and available on our eBook page at http://www.green-trust.org/ebooks/

Covering Sizing, siting, installation, and battery maintenance, it’s a good guide to putting together your own inexpensive system. Includes private discussion group and free updates.

We just got back from our trip to Anguilla. We helped Francoise set up her new solar power system. Two Kyocera 130 watt PV panels, a Xantrex C35 charge controller, a Trimetric Battery Meter, a Morningstar Microsine 300 sine wave inverter, and a 70 ah AGM battery, power up 3 Compact Fluorescent Lights, A LG WP-680N Washing Machine (260 Watts) and a Shurflo 12v pump. Two weeks of testing, and we were never able to pull the battery below 12.4 volts. The system consistently output 1.5 kWh’s daily. More pics at http://www.green-trust.org/Anguilla Solar/.