Knowledge of two incidents - sort of.
About ten years ago a Hydrocap on an L16 blew apart. Not our
installation; I suspect that it became plugged up or overheated, as
the array had been recently enlarged. Explosion was contained within
the battery enclosure; just made a mess.
About four years ago a small 12V automotive battery used only to
start a 6.5 Onan generator blew up, causing modest permanent hearing
damage to the homeowner. I wasn't there, and heard about it from
her. This wasn't a venting issue, as the battery was on the floor in
a ventilated room, but rather apparently a plugged cap in the
battery itself.
Otherwise, nothing.
Allan
On 12/15/2010 10:56 AM, Exeltech wrote:
38+ years in RE.
Knowledge of one incident (an off-grid friend).
Very sunny day. Very windy. My friend had both PV and a
wind generator (still does). He had just stepped out of
the room where the batteries were located when (as he
described it) he heard something like a loud gunshot. He
went back inside to find one of the L16s exploded, top
completely blown off, and case broken much of the way down
one side.
Had the incident occurred only minutes earlier, injuries
could have resulted. He has since relocated his batteries
to a dedicated (and vented) battery space.
Dan
--- On Wed, 12/15/10, Kent Osterberg <k...@coveoregon.com>
wrote:
From: Kent Osterberg <k...@coveoregon.com>
Subject: Re: [RE-wrenches] Battery based hydrogen
incidents
To: "RE-wrenches"
<re-wrenches@lists.re-wrenches.org>
Date: Wednesday, December 15, 2010, 11:21 AM
Sounds like, in general, that
the off-grid industry has been fortunate
to not have hydrogen explosions. That's good. No
explosions here
either. But one shouldn't take that as evidence that
it couldn't
happen. I don't believe this is a circumstance where
it is better to
be lucky than good. That's why I recommend doing the
calculations.
Kent Osterberg
Blue Mountain Solar
Dana wrote:
Ken
–
To
meet the flow have run 2 and 3 fans to meet
the flow. 2” output from
the fan into a 4” header with a matching 2.5”
inlet as far away on the
lowest portion of the battery box.
In
22+ years in off grid installations I have yet
to see or even hear of
one hydrogen explosion. I get repeatedly asked
why we have to go to the
efforts we go to for box and venting. I am not
able to provide even one
incident that I have heard rumor of.
Q
- How many battery based hydrogen incidents
have happened in our
collective experience?
Dana
Orzel
Great
Solar Works, Inc
E
- d...@solarwork.com
V
- 970.626.5253
F
- 970.626.4140
C
- 970.209.4076
web
- www.solarwork.com
"Responsible
Technologies for Responsible People since
1988"
Do
not ever belive anything, but seriously
trust through action.
Fellow Wrenches,
The discussion about battery venting reminds me
of a useful and
inexpensive program, BattMV,
for determining ventilation requirements per
EN-50272. EN-50272 is a
European standard used to determine how much air
flow is needed for a
room, I don't know of a equivalent standard used
in the U.S. It takes
a surprising amount of ventilation. For a
400-AH 48-volt L16 bank
charged at 57.6 volts and 24 amps, it's about 7
CFM just to keep the
%H2 down to 4%. A 12-volt Zephyr vent is good
for about 5 CFM! If
you think you are venting enough, take some time
and study this issue.
Kent Osterberg
Blue Mountain Solar
|
_______________________________________________
List sponsored by Home Power magazine
List Address: RE-wrenches@lists.re-wrenches.org
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: RE-wrenches@lists.re-wrenches.org
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
