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reddly Member	# Posted: 5 Mar 2013 01:47 Reply A strange curiosity hit me today. At Canadian Tire (or other box store) you can purchase battery chargers for your car (and I assume golf cart) batteries. These are those handy little things you just plug into to your wall at home and then boom a full charged battery in a few hours, they also work in your car off your lighter socket. So has anyone tried transporting battery power on the weekend? I don't mean as a full time solution. But many people on here say they go to the cabin every other weekend for a day or two and they conserve energy when there and have ways to generate power to some degree. But power from your on grid home is cheap, easy, and readily available. So is water and many other things. So just like these other commodities that you transport in why not power? obviously its not the best choice or a long term solution but for a short term, short stay power requirement what do people think could be managed? So I guess what I'm asking is has anyone done this? Apart from the obvious labor intensive issues to bringing a few batteries is it even possible? what kind of power could you store? what are some problems (other than weight) issues that might be faced?

Anonymous	# Posted: 5 Mar 2013 05:22 Reply I had one I got from Costco. I charged it at home and used it to charge my cell phone,lantern and run the Coleman on demand hot water pump in the cabin. When I took trips in the pickup truck I would take the battery and charge it with a inverter. It was nice to have because it also has a airpump on it. Great for inflation of air mattresses.

skootamattaschmidty Member	# Posted: 5 Mar 2013 06:40 Reply If you mean one of those power boxes with built in inverters yes I have done that for years. For many years I usd one to power the lighting in my pop up trailer. I either charged it with a solar panel or would plug it in to the truck when we were travelling. It worked great. I now bring it to the cabin along with another one I purchased. They are very handy and I have had to use to boost the truck before.

CabinBuilder Admin	# Posted: 5 Mar 2013 08:39 Reply I also did it for some time, before having a more permanent solution. The power box with built-in inverter was really handy for powering light tools (drills, jig-saws, etc.) while building the cabin.

reddly Member	# Posted: 5 Mar 2013 14:11 - Edited by: reddly Reply So for those particular cases you were actually using the inverter to run power from your vehicle to your appliances/lights? But has anyone tried bringing pre charged from home batteries? I don't see the power box (inverter, or other "plug into a running vehicle to draw power out of it") as a possible solution for any real length of time, If it was the case then a generator would be more appropriate than running my vehicle to generate power. I was more thinking having maybe 10-14 batteries on a dolly of some sort. I would have them at my house over the week to charge up from my cheap easy on grid house power, then on the weekend I could just wheel them out, toss the whole bundle into my truck. drive up, and then wheel them into the cabin and hook them up. Just like you would hook up to a normal bank of batteries except these ones dont stay there. when you're packing up on sunday you wheel them back out and take them home to hook up and charge again.

VTweekender Member	# Posted: 5 Mar 2013 15:20 Reply Quoting: reddly I was more thinking having maybe 10-14 batteries on a dolly of some sort. I would have them at my house over the week to charge up from my cheap easy on grid house power, then on the weekend I could just wheel them out, toss the whole bundle into my truck. You could certainly do that if you please, it would work if you wanted to go through that trouble.....most will bring one or two batteries and maybe a small inverter just to run a light and maybe a small TV or radio for a night or 2...

razmichael Member	# Posted: 5 Mar 2013 16:24 Reply Really big dolly for 14 batteries - might want to check the weight (depending on the type naturally). We used a pop-up trailer for 3 years on our land. I rewired the inside (inverter/charger), modified the internal converter and then put two T105s into a battery box on a small two wheel dolly from Costco. The batteries are wired with /02 gauge cables and anderson plugs (with a cut-off switch). At the time no solar so we did much what you talked about. Take the batteries home after the weekend (or when needed) and charged them at home. With LED lights and cautious use (except for my wife using a hair dryer once a day) we could easily get 5-6 days use). At about 120 lbs this was not easy but did the trick. Last fall we put up the cabin and I moved the components inside (still wiring up) and am doing the same thing with the batteries until I get the panels up and wired - although more often now I take up our generator to use for the building work so can charge with this).

reddly Member	# Posted: 5 Mar 2013 19:38 Reply Raz, was wondering about how much power does the battery store at full charge (t105s in your case) I figure as a rough estimate between 400-600 watts every hour. Sorry I'm still all kinds of confused on watts vs volts vs amps. But I know everything in the house going will be drawing between 400-600 watts an hour.

razmichael Member	# Posted: 5 Mar 2013 19:59 Reply I assumed you were looking to power a few lights and maybe a small water pump based on your initial reference to a Canadian tire type power pack - not a house! A couple of T105s provide about 220 amp-hrs (consider maximum 50% discharge and you are looking at 100 plus amp-hours (and you need to consider the 15% or so loss depending on the inverter if you need 120VAC. Considering these are relatively high end deep cycle batteries you can see that your planned consumption is not something you can cover with a portable battery bank! Can you provide a bit more details on what you plan to power?

Anonymous	# Posted: 5 Mar 2013 20:52 Reply If you start transporting 10 - 14 batteries on a regular basis I think sooner or later you will have an accident and battery accidents are seldom without bad results. Not to mention I can't stand the thought of handling that much weight every time I want to go and return.

reddly Member	# Posted: 6 Mar 2013 00:28 Reply Raz help me out with understanding amp hrs and all that. I swear I've googled this and for some reason i can't wrap my mind around amp volts and watts. so 220 amp-hr means if i ran 100amps per hr (draw from the battery) then i would have just over 2 hrs right? Or do I have this totally off. but for instance i have a home made led. it has 25 1 w white leds. so thats 25watts an hr right? and each draws 320m amps ( so 0.32 amps) so.. thats .32 x 25 so thats like 8amps. so thats 8amps per hr? is that right? am i doing something wrong here? well i know that there are at least 3 led lights that we use at home here that I would like to use off grid. There are a few other things coolers, fans, and then there are things that I want there that aren't there. computer, tv, satellite etcetc. Until I can get solar, wind (and hopefully micro hydro) I'm pretty limited in my options. Obviously limit power use, etcetc but there are a few of us and yeah we are going to end up using more power than we would ideally want. I don't know how many amps everything will pull (because i thought i should be looking at watts) and i know that it'll be around 600 watts if everythings on and going. the real killers are the heater, ac, and there is an electric stove i have access too. all killers on the power. 10-14 batteries on a dolly wouldn't be bad. just roll it to the truck. toss it in.

VTweekender Member	# Posted: 6 Mar 2013 03:11 Reply You would be much better off getting a good fuel saver 3000W generator and just use that, like a honda 3000....cost about the same as the batteries......

Anonymous	# Posted: 6 Mar 2013 06:59 Reply I would think about the safety aspect. The first type of battery you asked about was fully self contained. Built to safely transport. Hauling a battery bank back and forth is not safe. Gassing,leaking and explosions are some of the hazards. Code in some states is to build a seperate building to house a battery bank.

razmichael Member	# Posted: 6 Mar 2013 07:00 Reply Reddly, I would suggest you take a look at other threads in this sub-forum and, for a basic primer the two parts of The 12 Volt side of life. These are a bit outdated reference the technology but give you a start. Overall, as soon as you start talking about electric stoves, AC etc then you are talking about a major off-grid system, not something you pack a couple of batteries back and forth. I think you need to really figure out what you want to do and whether off-grid, generator (as suggested by VTweekender), on-grid etc (or combinations). Although this is covered in the "12 volt side of life", regarding your example with the batteries - if you have 220 amp-hours you cannot use all of this and generally would not go down below 50% (I'm considering true deep cycle batteries as this figure would be much less for non-deep cycle).

reddly Member	# Posted: 7 Mar 2013 14:08 - Edited by: reddly Reply Thanks guys, I'll be looking at the 12 volt side of life. I am also going to experiment a little with this. Obviously not on a large scale at the moment but I'm going to see what I can accomplish with 1 battery and then work on scaling it, IF it will work as a temporary stop gap to my issue. The main issue with a generator (and eventually I'll simply have no choice but to get one) is not the initial cost of the generator but the ever mounting fuel cost on top of it. I would prefer a larger gen. as that way it's use isn't limited if my power needs expand. With that being said I'm partial to diesel (1. the upkeep seems to be less 2. reliability 3. bio diesel home brew ). However diesel seems to have taken a sharp jump in price lately. Aside from this noise is always a concern. I don't worry to much about neighbours but it's hard to enjoyed unspoiled wilderness with an engine running. Quoting: Anonymous Hauling a battery bank back and forth is not safe. Gassing,leaking and explosions are some of the hazards. Code in some states is to build a seperate building to house a battery bank. Well .... being from Canada state law doesn't concern me all that much However, I do get your point. So let me throw this out there. I was considering something along the lines of a little red wagon with batteries in it. Nothing super technical, and obviously I wouldn't use an actual childs toy wagon but this might give an idea of what I had in mind. Something simple and easy just to move weight. Quoting: razmichael as soon as you start talking about electric stoves, AC etc then you are talking about a major off-grid system I realize that a battery bank would not be able to keep up with such appliances, at least not on any full time, or regular schedule. I did look at some "golf cart" batteries that claimed they could be discharged down to 20% (so using 80%) without any adverse effects. I'll try to find the link as apparently I didn't save it. I figured if these could be used to 20% they might work for powering life at the cabin until a more permanent and standard solution could be implemented. At anyrate I'm going to take a read of 12 volt life and then try to understand some more in regards to what might be possible, if any of this is possible at all. EDIT: so I found one of the 2 websites I was reading about "extreme discharging" http://www.solarray.com/TechGuides/Batteries_T.php 2/3 down the page "steps to success" #1 claims that the batteries they recommend (sales pitch???) that they can be completely discharged and still be fully recharged roughly 1000 times. Also the chart at the very bottom of the page gives estimated recharge cycles with 80% discharge. I don't think I believe this but, if its partially true it might offer some flexibility.

reddly Member	# Posted: 7 Mar 2013 14:34 - Edited by: reddly Reply 12 volt life L-16 11.69 X 7.13 X 16.69 114 lb. 340 to 380 Amp hours 6 volts if 2 of these massive 120lbs batteries were hooked up in series ( i think its series) then it would produce 12 volts correct? and have 700 amp hours? EDIT: math was off would need 4 batteries, 2 series of 2 in parallel. so 4 batteries total. Using the previous example of my home made (experimental fun) led lamp with 25 1 watt 320mA leds, (25 x .32= 8amps) thats 8amps per hour (I assume but still unclear on all this) So for easy math lets just pretend we're in a perfect world with no loss to heat, resistance, or anything else (yes I know this isn't the case but just to get a concept in my mind of things) would that mean that 2 of these monster batteries would power my 1 led lamp for (700 amps in 2 batteries)/(8 amps led uses) = 37.5 hours ???? yes obviously this is not a good solution on any level. packing 240 lbs of batteries to make it work BUT, IF the general math is right powering an led for 37 hrs would mean not having to change these for perhaps months on end. even at 6 hrs use per weekend, every weekend thats 5 weeks with still leaving a charge in the batteries. am I way off here? Am I thinking of this all wrong? edit: i would also like to add a small wagon, might make for a mobile bank. http://www.watchman2012.com/articles/batterybank.shtml

Just Member	# Posted: 7 Mar 2013 17:29 Reply I would be suprised if your led light burns 25 watts .more than likly it burns 1 watt and will replace a 25 watt incandesent bulb.my led bulbs use 1.4 watts and replace a 40 watt bulb . we have a very small system consisting of 2 , 140 , amp hr wallmart deep cell batteries and 55 watt solar system ,we never run out of light ,water ,entertainment[on a average weekend] you will figer it out it just takes time ,at least it did for me..

reddly Member	# Posted: 8 Mar 2013 00:23 - Edited by: reddly Reply The led is homemade and is 25 single leds each is labelled as 1w and .320 mA. the driver I used for them is a 30w driver (to my understanding this means I can't run more than 30 single 1w LEDs) It's not a bad DIY job, one of my first succesful experiences with soldering and I rather enjoyed the experience so I've managed to build a few prettier ones. However this all deviates from my original question and concept.

razmichael Member	# Posted: 9 Mar 2013 08:37 Reply Quoting: reddly if 2 of these massive 120lbs batteries were hooked up in series ( i think its series) then it would produce 12 volts correct? and have 700 amp hours? . Wrong - Two in series provide 12 volts but the amps stay the same. Parallel is the opposite (voltage is the same but amps goes up). I'll admit at this stage I'm not completely sure what you want to do. Taking a couple of batteries back and forth is fine for a small system but I cannot see the practical side of anything larger. I would not want to be loading and unloading a large bank of batteries for all the safety reasons mentioned above and for the safety of my back. I did that with my two T105s for long enough and hated it. I would be really careful doing hypothetical calculations ignoring a bunch of real world factors because these are not trivial and have a big impact. Assuming you did want to discharge the batteries down to 10 or 20% (I would not), you need to check the reduced voltage level (with any line voltage drop - google voltage drop calculators) and you may find the the low voltage will not power what you need powered anyway. Most inverters would shut down unless you could override the low voltage setting. If you are looking at including an inverter you need to consider the up-front loss which could be 15% or more. Any appliance with a motor tend to have much higher start up demands than steady state. All these things add up quickly and you may find your system of x batteries needs to be double this. These systems do not always scale well. A small system like I have (or Just as was posted earlier) work fine on 12VDC, possibly with an inverter for occasional 120VAC use. But 12 volt systems have issues with wire size to reduce voltage drop, types of switches to use, availability of 12 VDC appliances etc. For anything larger you will look at 24V or 48V systems. You will also very quickly decide to run everything through an inverter so you are using 120VAC components throughout. This impacts wiring decisions and lots more. In general, changing from one general design to another will not always be simple and you end up throwing away pieces (a good 12v inverter will not likely work for 48V unless you pay up front for one that can - if it exists). You want to think through your final plan (how much power, solar, wind etc etc) first and then keep this in mind when experimenting or designing stages. If you do some real world calculations for your likely needs based on including AC, a stove and all those things you listed, you will have a much better idea of what would be needed - this may cause you to take a second look and wonder if you either want to go on-grid or look at cutting back you needs (i'm assuming that this is a cabin or cottage we are talking about). Please don't take any of this as being critical - I fully appreciate the fun of exploring options and I am only providing my opinion and some things to consider

reddly Member	# Posted: 10 Mar 2013 07:02 Reply I cant thank you enough for all the insight, help and figuring out the practical applications of this thought I had. Anyways I have a lot more figuring out to do before continuing and what is and isn't possible. such is life I suppose. It's all about figuring what we can do without until we can find a way to make it work with what we have. as for the critical thoughts thats why I'm here. I'm a hair brained semi unrealistic dreamer of whats possible. A lot of what I work with is hypothetical and deals with "if" and such. But once I have something in mind I do for the most part start with real world experiment and applications to my life. So before I electrocute myself or start doing lunges with 400lbs of batteries on my back its always good to hear other peoples experiences and ideas. bottom line. I really appreciate the time you guys have given me here. Thankyou.

razmichael Member	# Posted: 10 Mar 2013 10:21 Reply Quoting: reddly But once I have something in mind I do for the most part start with real world experiment and applications to my life Lets not forget how much fun it can be to experiment (thought or real). My problem during our long cold winters is I have too much time to play with stuff. I'm finishing up the new power distribution system going up in the spring. My wife is not that thrilled about a table full of stuff in our "TV" room but it keeps me off the street. Sadly I left some components up at the cabin so cannot finish all the pre-wiring and put together the control panel (but I do have great drawings of it!). Next up is the water system! Enjoy the adventure!