<html><body><span style="font-family:Verdana; color:#000000; font-size:10pt;"><div>I've seen one, and picked up after another.. the first was at my brother's farm in like 81.. seems he took to parking the tractor on the back walk (inside the barn -- in winter) because he had been having starting problems <span>(a 6 volt set up as I recall)<span id="GD__CURSOR"></span></span>, so it had been on charge. I had just walked in and was walking toward the tractor when Leon tried to start the thing.. It might have turned over once when I heard what sounded like a shotgun and saw a cow's ass end lift off the ground about a foot.. seems one whole end of the battery came off and hit that cow square in the butt... more recently I was called to a grid tied PV system that "stopped working".. we got there and found battery parts and pieces all over the basement (and funny stains on the ceiling).. the other batteries were dry as a popcorn fart.. asked the owner about watering and he replied "I need to water these things?".. the system was a few years old.<br></div><div><br></div><div><br>Dan Brown<br>Foxfire Energy Corp.<br>Renewable Energy Systems<br>(802)-483-2564<br><a href="http://www.Foxfire-Energy.com">www.Foxfire-Energy.com</a><br>NABCEP #092907-44</div><div><br><br></div>
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-------- Original Message --------<br>
Subject: Re: [RE-wrenches] Battery based hydrogen incidents<br>
From: "Joel Davidson" <<a href="mailto:joel.davidson@sbcglobal.net">joel.davidson@sbcglobal.net</a>><br>
Date: Wed, December 15, 2010 7:51 pm<br>
To: "RE-wrenches" <<a href="mailto:re-wrenches@lists.re-wrenches.org">re-wrenches@lists.re-wrenches.org</a>><br>
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</style> <div><font face="Arial" size="2">I have sold thousands of off-grid PV systems and hundreds of on-grid PV systems with batteries. In 1984, one customer located 30 miles north of New Orleans with an off-grid PV system and T-105 batteries reported that a battery exploded. The cause was a clogged cell cap vent that trapped H2 that was ignited by transient current from a nearby lightning strike (that also destroyed his charge controller). About 6 months later another nearby lightning strike fried another controller. The PV array was a few hundred feet from the home. The owner wired the PV array and home equipment ground rods together and made sure that cap vent holes were kept clean. Subsequent lightning storms caused no problems.</font></div> <div><font face="Arial" size="2"></font> </div> <div><font face="Arial" size="2">The only exploded battery that I actually saw was also in the 1980s at a Sears service station. An automobile battery had exploded and tore a hole in the car engine hood.</font></div> <div><font face="Arial" size="2"></font> </div> <div><font face="Arial" size="2">Joel Davidson</font></div> <div> </div> <div>----- Original Message ----- </div> <blockquote style="border-left: 2px solid rgb(0, 0, 0); padding-left: 5px; padding-right: 0px; margin-left: 5px; margin-right: 0px;"> <div style="font: 10pt arial; background: none repeat scroll 0% 0% rgb(228, 228, 228);"><b>From:</b> <a target="_blank" title="dana@solarwork.com" href="mailto:dana@solarwork.com">Dana</a> </div> <div style="font: 10pt arial;"><b>To:</b> <a target="_blank" title="re-wrenches@lists.re-wrenches.org" href="mailto:re-wrenches@lists.re-wrenches.org">'RE-wrenches'</a> </div> <div style="font: 10pt arial;"><b>Sent:</b> Wednesday, December 15, 2010 8:10 AM</div> <div style="font: 10pt arial;"><b>Subject:</b> [RE-wrenches] Battery based hydrogen incidents</div> <div><br></div> <div class="WordSection1"> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;">Ken <o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;"><o:p> </o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;">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.<o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;"><o:p> </o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;"><o:p> </o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;">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.<o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;"><o:p> </o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;">Q - How many battery based hydrogen incidents have happened in our collective experience?<o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;"><o:p> </o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;"><o:p> </o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;"><o:p> </o:p></span></div> <div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext;">Dana Orzel<o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext;">Great Solar Works, Inc<o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext;">E - <a href="mailto:dana@solarwork.com">dana@solarwork.com</a><o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext;">V - 970.626.5253<o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext;">F - 970.626.4140<o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext;">C - 970.209.4076<o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext;">web - <a href="http://www.solarwork.com">www.solarwork.com</a><o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext;"><o:p> </o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext;">"Responsible Technologies for Responsible People since 1988"</span><span style="font-family: 'Calibri','sans-serif'; color: windowtext; font-size: 11pt;"><o:p></o:p></span></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext;">Do not ever belive anything, but seriously trust through action.<o:p></o:p></span></div></div> <div class="MsoNormal" style="font-size:12pt;"><span style="font-family: 'Century Gothic','sans-serif'; color: windowtext; font-size: 14pt;"><o:p> </o:p></span></div> <div> <div style="border-width: 1pt medium medium; border-style: solid none none; border-color: rgb(181, 196, 223) -moz-use-text-color -moz-use-text-color; padding: 3pt 0in 0in;"> <div style="font-size:12pt;margin-left: 0.5in;" class="MsoNormal"><b><span style="font-family: 'Tahoma','sans-serif'; color: windowtext; font-size: 10pt;">From:</span></b><span style="font-family: 'Tahoma','sans-serif'; color: windowtext; font-size: 10pt;"> <a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">re-wrenches-bounces@lists.re-wrenches.org</a> [<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">mailto:re-wrenches-bounces@lists.re-wrenches.org</a>] <b>On Behalf Of </b>Kent Osterberg<br><b>Sent:</b> Tuesday, December 14, 2010 12:07 PM<br><b>To:</b> Wrenches<br><b>Subject:</b> [RE-wrenches] Battery Venting<o:p></o:p></span></div></div></div> <div style="font-size:12pt;margin-left: 0.5in;" class="MsoNormal"><o:p> </o:p></div> <div style="font-size:12pt;margin-left: 0.5in;" class="MsoNormal">Fellow Wrenches,<br><br>The discussion about battery venting reminds me of a useful and inexpensive program, <a target="_blank" href="http://pocketengineer.design.officelive.com/battery_ventilation.aspx">BattMV</a>, 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.<br><br>Kent Osterberg<br>Blue Mountain Solar<o:p></o:p></div></div> <div> </div><hr> <div></div>_______________________________________________<br>List sponsored by Home Power magazine<br><br>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><br><br>Options & settings:<br><a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a><br><br>List-Archive: <a href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a><br><br>List rules & etiquette:<br><a href="http://www.re-wrenches.org/etiquette.htm">www.re-wrenches.org/etiquette.htm</a><br><br>Check out participant bios:<br><a href="http://www.members.re-wrenches.org">www.members.re-wrenches.org</a><br><br></blockquote> <hr>_______________________________________________<br>
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