First time energy setup advice? (battery+solar)

Im not planning on running a large inverter no. I have a small 150watt inverter I may use with my laptop. But ive also seen $30 dc laptop chargers on amazon that dont require an inverter at all. The only thing i'd use the inverter for is charging my laptop. I was just thinking to myself what are my real end goals for my battery power. All I really want to do with my battery power is power an led light or two. Recharge my laptop in the evening (if needed), and be able to run the furnace when its cold. I bought a $10 aa battery programmable thermostat. Im not sure if it will even work with my single stage heater. But my hope was I could set it up to keep the temp in the lower 60s around sunset till 10pm or so and then turn off or way down for the night. Then have it kick back up around 6am for an hour so I can actually get out of bed. Rest of the night lots of warm blankets would go far, I like sleeping in the cold anyways. Anytime I wanted to work during the day, or run the microwave, or water heater I could turn on the generator for a bit.

Jonnygsx wrote:
Do I really need a trimetric monitor? I can get a $10 voltage monitor on amazon which will give me an idea right? For the price of a trimetric I could get another solar panel. One thing im finding difficult is that everyone on this forum is that everything is all out top end. It is hard to find advice for limited budgets.

My opinion is that you don't need a Trimetric, the $13 Amazon monitor I linked to above works fine for a snapshot of the situation. Like you said, you can get another panel for the price of the Trimetric. I used to think I'd want all that data that the Trimetric provides, but after two summers on my system I don't feel the need anymore and have no plans on a sophisticated monitor. A snapshot of the voltage is all I need. Since I know what my charge controller setpoints are programmed to, I can tell by the voltage what state the controller is in and that is enough info for me. When the sun goes down, the voltage meter reading allows me to estimate my batteries' state of charge. My charge controller does allow for interface with my laptop and I can access all the charging data that way. I did that a lot during setup, but then it is a set it and forget thing.

My plan before I started was the same as your's. I had a nice Yamaha 2400 generator already so I knew I could always bail myself out if the solar wasn't working. My converter is a WFCO smartcharger, although these are known to not reliably perform as advertised. It's better than a single stage trickle charger, though. My plan was to start with a 140W 12V panel and I would use wiring and a controller that allowed for plenty of expansion. Since the panel was on sale I went ahead and got 2 of them and that is still the system I'm running today. I've upgraded to 2x6V batteries in series which gives me way more Ah than the 2x12V marine batteries that came with the TT.

Are you going to run an inverter?

Do I really need a trimetric monitor? I can get a $10 voltage monitor on amazon which will give me an idea right? For the price of a trimetric I could get another solar panel. One thing im finding difficult is that everyone on this forum is that everything is all out top end. It is hard to find advice for limited budgets.

Probably on group 27 battery will be enough for your needs as will the 120 Watt solar panel. A good place to start is with buying a Trimetric charge controller so you can monitor accurately how much charge is coming out of your battery, how much charge actually remains, and how much charge is going back in when plugged into shore power or using the generator or the solar panel.

I prefer the solar panel approach as they keep the battery charged with nothing needing to be done by you and they will recharge the battery after a night's use automatically as well. No need to fire up the generator and stay to attend it. With solar once it is installed you can forget about it and let it operate.

One panel should be able to recharge your battery in 2-4 hours depending on the weather and time of year and amount of shade where the trailer is located. If you add a second battery that may change the charge time to 4-8 hours but that is still all that you need. You start the evening with the batteries at 100%.

Its a chinese who knows generator. http://www.amazon.com/Magna-3000-Portable-Inverter-Generator/dp/B0015F4JG0

I was looking at this 45amp converter. http://www.amazon.com/Progressive-Dynamics-PD9245CV-Inteli-Power-Converter/dp/B000GANZZ6/ref=sr_1_1?ie=UTF8&qid=1386054514&sr=8-1&keywords=Progressive+Dynamics

What type of 3kw genny do you have? Is it an inverter type like a Honda, which throttles down when there is no much load or is it a screamin demon that is running at full speed regardless of load?

Also if you are in need of a new converter you might want to consider 'marinising' your trailer & do it the way boats are set up with a 3 stage smart inverter/charger or at least a 3 stage smart charger. This eliminates the cheap & nasty single stage converter/charger. RV builders don't do it this way because, well, it costs more but you will get longer life out of batteries with a smart charger. The better smart chargers have a controller so that charging levels can be set depending on the size & type of battery bank.

Mine runs like a boat. All 12V needs are taken from the battery bank. The smart charger replaces as needed at the rate needed.

The plan in the long run is to deck out the roof in solar. But I can't do that initially and since im not sure how much power ill be using or needing I dont think it would make sense to go all out right away anyways. My hope is to try and get a basic solar install that allows it to be upgraded in the future. If I were to say have a 120watt panel on the roof and controller would I still want to disconnect the batteries when I wasnt using it? Or should I just let the panel maintain it?

If I had to pick between buying a 120watt system or a new converter what would you recommend? My thought was i could disconnect the todd converter completely and let the solar refill my batts during the day while im on gen power?

Jonnygsx wrote:
Alright Im beginning to feel a bit overwhelmed here. If only money grew on trees.

Since I have a generator I'm feeling like my best bet is to start with a good battery setup and worry about the solar later. I have to start somewhere and I can't do it all straight away. I'm thinking I will go for 2 6v GC2 batteries from Cost co. This is a dumb question im sure but when you see batteries rated at 200Ah. You are only actually able to use half that correct? Because you don't want to discharge a battery below 50%?

That brings me to my next question. What is the best way for me to monitor my batteries? I've seen remote digital monitor setups but they are all $150+ Is there a cheaper option or is walking outside with the volt meter the only cheap option? While I mentioned waiting on the solar initially I did see that many of the solar charge controllers have digital displays indicating charging current and batt voltage. Can that be used to monitor voltage instead of using a separate monitor built just for checking voltage? What if I were to buy a charge controller and only attach it to the battery as a monitor initially?

Since I'm going to be using the generator I want to have a good converter to make sure these batteries last. The current one in my trailer is a TODD PC30 single stage charger. Can anyone recommend a good 3 stage? How does the amperage listed affect the different converters?

Finally the whole reason I got on this solar trip was initially over concern of maintaining the battery while in storage. If I dont have a trickle charger and no solar/solar maintainer is my battery at risk during storage? Is just disconnecting the terminals enough to ensure its ok the next time I head out?

Thank you for reading my novel ;) JJ

Good choice on the 6 volt Costco's. The last thing you want to think about is if your new batteries are being run too low when you're camped at night, it's cold outside, and the furnace is running. If you run the pair of 6V batteries down quite a bit, they will recover. Try that with an inexpensive 12V marine hybrid battery and it will die shortly.

The Todd converter you have is miserable for charging and there are a lot of posts about them failing. A Progressive Dynamics converter would be a good choice. Call Randy at Bestconverters.com, he's a decent fellow and their service is excellent.

There is no reason you have to spend thousands on solar to help your situation. You can start with a maintenance sized system and move up from there. A 50w solar module wired directly to your batteries will keep them full if your rig is used once a week, parked the remainder, and the sun shines. You want to make sure the new batteries are disconnected from the trailer when not in use, there are parasitic draws from circuit boards and alarms that will drain your batteries in a week. You can find a cheap DC meter on E Bay or online merchants that displays your battery voltage. Look up a voltage chart of what percent of charge is at different voltages and go from there.

A lot of folks balk at the capitalization costs of solar (at least a system big enough to meet all their electrical needs). They feel that operating a generator and fueling it is a more economically efficient way to meet their needs. Some of these folks are right. Most are dead wrong. If you consider the cost of the generator, initially, the cost of fuel, the cost of maintenance, and it's usable life, solar can be the winner. The downsides of solar are that it's almost impossible to run Air Conditioning and, unless you get a large inverter, microwave cooking, electric coffee makers, and hair dryers can't be used.
The upside to a decent sized solar system is that generator costs and the hassle involved of moving it, listening to it, and carrying fuel are eliminated or greatly reduced. Battery health is also increased because the solar is always charging your batteries.

Good luck with however you choose to get electricity. If you get some solar, you'll see how good it can be.

I know it gets overwhelming but that's because we all do it differently, have different needs and budgets. Take it slow so that you have a chance to understand your needs and you will be able to develop a solution that fits you and your budget.

Can you run a generator daily to keep up a single 12v battery? Lots of us have or do so on a regular basis. There is a poster here that runs his twice a day but he has so pretty heavy duty power needs. The downside is gas isn't cheap and you have to listen to it. When in a campground not only do your neighbors have to listen to it, there may be restrictive times that you can run it.

$3 a watt for solar is a bit pricy for me, then again I'll have 450w running this year and will have less than $400 into the system. I did it by watching craigslist and ebay while having the patience to wait for the good deals. I also don't worry about having top of the line gear because up where I go, there is no one to be impressed. I just need it to function.

Here is a link to a 200w system for $289.

click

That is slightly smaller than the 230w system that kept our single 12v battery up all summer.

Take it slow and research. After a while you will have a good idea of what you need.

Hi Jonny,

The very first step is to conserve. Replace the most used incandescent lighting with inexpensive led's. (ebay?)

Solar costs only once. Currently the "toll" to get "on board" is running around $3 per watt on a DIY installation. Rule of thumb on size is between 150 and 60 watts of panels per 100 amp-hours of storage. It is a bell curve, so a small battery bank requires more wattage than a medium size bank.

Here is a simple flow chart.

Budget-->Energy Audit-->Battery bank size-->number of watts-->PWM or MPPT.

Here is a link to the rather special spreadsheet which includes an energy audit that N8GS has created to help size solar battery charging systems!
Solar Spread Sheet N8GS

For a nice explanation of solar, try this link: Golden rules of solar