VOLTS Whats AMPS, ....Did I do it right?

[TucsonAZ]

I think people should start with listing a budget to help us cater our advice with what's possible on that budget.

My advice to you, just dive in and make adjustments as you better learn your needs. One wise idea for you may be to stock up when you have a full battery and some sun still shinning, charge a laptop, ipad, rechargeable batteries, whatever you can, this way on the days you're running short on sunshine you have something of a stockpile to pull from.

Good luck, good job and enjoy...

 

[RogueRV2]

Hi Yawpee,
We see you are using a marine type battery and not a true deep cycle. Marine type batteries reported only last about one year when used in a solar system and cycled as most would use a deep cycle battery. Often the marketing is misleading and folks mistakenly purchase a 'marine' type battery. 122AH it is lower in capacity than 2 deep cycle 6 volt batteries that are rated for about 230 AH on average, and watt many folks are accustomed to at a minimum. Yet, your system can take care of basic needs quite well if managed smartly.

To get the most from your system, do not use inverters or transformers, and charge your devices during the day time after the battery is mostly charged. If one takes $1 dollar or 1 amp out of the battery, you'll need to put back $1.15 or a $1.25 back into it. If the battery is near full, the excess power from the panel can go directly into the device, and for every $1 of power needed, only $1 dollar is used. Your solar system used in this way is 15 % to 25% more efficient and you'll need less solar to get by on. Anywhere electrical power is converted or transformed from one voltage to another higher or lower voltage, a significant amount of power is lost in the process, sometimes as much as 25%. Use only 12vdc devices when possible, and avoid transformers and inverters as if these are a pox. For lighting, use rechargeable batteries to power a LED headlamp or similar. There are 12vdc AA and AAA battery chargers sold at the big box stores, avoid the rapid recharge types that use a cooling fan. These are less efficient and reduce the life of your rechargeable. One 100 watt panel laid flat on the roof might provide during peak hours, 3.8 amps per hour. It is about 65 to 70% of it's rated 5.5 amps. Tilt it up and you'll get about 90% efficiency, or Our laptops consume 45 to 65 watt max per hour, or 3.75 to 5.4 amps at 12vdc when running and charging it's battery. 45 watts/12vdc = 3.75 amps. An 11 watt 12vdc Compact Florescent bulb uses 11watts/12vdc = .92 amps per hour. Budget your energy use wisely and that marine battery will serve you better and longer if you keep the depth of discharge as low as possible. That is, do not use it like a deep cycle and run it down to 12.3 volts or 50% of capacity , but use it only to carry you through cloudy days or as a reserve. And of course use the alternator to charge it as well.

 

[offroad]

In other news.... Hope this is not too much of a jump in the original discussion. Seems Obama is going to try and bootstrap a solar power installation corp. going to set up classes and training for veterans to do solar power systems installations. So if you are a military veteran you might look for those classes being offered or jobs being created in the next year.

 

[Yawppy]

Oh boy think my brain has been fried, still grappling with all this info, and have to say going to have to just do a good ol field test, learn more as I go type deal, as for now this set up is all I can afford,seems like it will do for low consumption, and yes, am hoping to be able to upgrade the battery, and add one more 100W panel in the future, but for now, all I have to spend is spent.

Sounds like if managed properly it will suffice, and I realize no microwave or fridge, fine with that, just as long as the battery can operate the LED TV and lap top, I'm fine, or so I hope!

Now starting tomorrow going to do some videos for utube, as I begin installation, noticed one video that did a decent job of showing the steps and such, but not many others in regards to vans, RV's oh several, but still I am nervous as heck drilling holes in the roof...still looking at options and sealant options as well, also seems this panel blows all stealth... but what else can I do?

Love to hear if anyone has suggestions on sealants for the bolt holes, have some ideas, silicon, dicor, and even rustoleum leak seal, to mounting a few wood blocks with liquid nails, so any suggestions well appreciated, and thanks again for all the info already!

 

[RogueRV2]

In full sun, the panel flat one the roof should make 5.8 amp per hour. Figure about 3.75 amps per hour to run the laptop and similar for the LED TV. 5 hours of sun will deliver about 5.8 x 5 hours of solid sunshine = 29+ amps for the day. You gotta deduct as much as 25% to account for the power lost when putting power back into the battery. 290 amps - 25% loss = 29 amps - 7.25 amps lost = 21.75 amp put back into the battery divided by 3.75 amp that the laptop will use = 5.8 hours of laptop time in used at night for every 5 hours of sunshine. Keep the battery voltage above 12.3volt, check the battery with all the power off, and it will be at about a 50% discharge and last for 3 to 5 years or more if it is a true deep cycle. A marine/RV battery might last a year with this kind of use, so perhaps figure on getting a true deep cycle battery before getting the next panel. The battery is the heart of the system.