The real point is that the Xantrex guy is correct from a scientific
stance. Experimental battery cycle life data shows that some golf cart
batteries (T105) do have more rated cycles to 80%DOD than the Trojan
L16. (750 vs about 600) A really crappy golf cart battery (some have
cycle life below 400 cycles) isn't as good as an L16, yes. You have to
base your decision, and your mouth, on test data for the batteries
considered. Also, you must always compare at 80% DOD, for an apples to
apples comparison. Its usually a clue if a manu doesn't publish their
cycle life data. Of course you must temper the golf cart vs L16 decision
with good paralleling technique.
We use golf cart batteries (never more than 4 strings), jump straight to
the HUPs for larger banks, and skip the L16s all together. They just
don't make sense when you look at the cost/ amp hr vs their lifespan.
The only time I could see using L16s, was if the battery bank
requirements were beyond 4 strings of golf cart batteries, and the
customer just could not afford the HUPs, or were going to sell the
property soon, and wouldn't appreciate their long term value.
I've spent a lot of time looking at cycle life data, comparing costs,
adding in maintenance and replacement labor, etc..
L16s are serious losers on a $/ kwh operating cost comparison, so this
is a chance to up sell the customer to HUPs (or equivalent) and make
both of you happier in the long run.
Ray Walters
On 9/16/2011 10:15 AM, Larry Crutcher, Starlight Solar wrote:
Hi Ron,
Have a look back a few months ago to the discussion about multiple
battery strings. My synopsis: large, parallel banks are not good;
fewer strings are always better. How large a bank are we talking about
here?
Scientist?? That sounds kind of like "Yea, I been a 'lectrician for XX
years...", something I have heard hundreds of times. It's just pride
saying "Look, I can pee that far too!" when in reality they are
clueless about DC power systems. I'm ranting but my point is you
should convince your customer that a hands-on, real world experienced
professional has a much broader understanding of RE system intricacies
than a "scientist".
Larry
*From:* Ron Young <mailto:[email protected]>
*Sent:* Thursday, September 15, 2011 5:11 PM
*To:* RE-wrenches <mailto:[email protected]>
*Subject:* Re: [RE-wrenches] battery cycle life, US Battery
Hi Larry,
Client has asked me to compare the cycle life because he is upgrading
a large battery bank and has been convinced by a Xantrex "scientist"
that golf cart batteries are superior to L-16's even though it
involves twice as many batteries, connections, cells, footprint etc.
So to convince his purchasing committee he wants to know the
difference in cycle life between a U.S.B 208 and a Surrette S-460.
Ron
_______________________________________________
List sponsored by Home Power magazine
List Address: [email protected]
Options& settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules& etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
_______________________________________________
List sponsored by Home Power magazine
List Address: [email protected]
Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
