Roof Mounted Solar Panel Vs Honda Generator

[pods8]

In the case of the roof, maybe not so much if you don't have much else up there, but for where I have it, the size and weight make a big difference, especially when I take it out of the slide and move it around.


You were talking roof mount when you stated the weight issue, not your removable slide out. In general though a little less definitive on your statements and a bit more here's a product with X & Y attributes to let people make their own decisions of which factors matter in their situation is a good idea. The panel I bought is going on a powered roof, with nothing else on it, and also will help balance out my lift system since the front is cantilevered, thus there is no point in spending 2.5x for a panel that is 10lb lighter.

For other folks just adding 15lb will probably make they want to add gas shocks on their rig, for the price difference of the 25lb panel one could consider getting that one AND the shocks they'd probably want anyways and still come out ahead. But each person can decide what they want and feel justified in spending.

I did series I think...?....

Either way I simply wired it to the same terminal posts as the main panel, on a separate set of wires. I unplug the 100 watt panel from the bulked when I am not using it to prevent voltage leak back which only amounts to .5 volts.


You just described parallel.

 

[pods8]

OK, Ramblinman, order that panel and the following controller & remote meter.


FYI: For anyone thinking this combo + a remote temp sensor you might want to look into this unit as well which is the same price (as those three components combined) which was received well on the reviews at windsun.com I had read over. Rogue MPT-3024 charge controller Fairly powerful package but overkill for our campers unless you start running a large array. It appears to display a lot more info though if you wanted it. Anyways just more food for thought in the MPPT controller segment.

 

[Ramblinman]

Kodachrome, Thanks for the info! I spoke with Stan, sounds like he can help if I send them directly to him.

One question if anyone cares to answer, are the Sears Die Hard Group 31 batteries AGM? In speaking with Stan he says that FWC prefers this style (Glass Mat?????) because you do not have to vent them. You can turn them upside down and every thing is sealed.

Anyone?

Also am I right to say that they will be bigger than the FWC DEEKA Group 24 batteries? I ask so that I can determine whether they will mount directly in to the same box that the 24's will mount.

 

[craig333]

The die hard platinum is the agm battery. http://www.sears.com/diehard-automotive-battery-platinum-p-1-group-size-34/p-02850034000P

I'm getting cold just reading this post. Remind me to turn down that invite to tag along with kodachrome on a winter trip

If solar doesn't cut it for winter use or whatever a 54db honda is certainly preferable to firing up the cummins to charge the batts.

I really wish I had the time to spend camping to really worry about power. As it is now I can run heater, freezer and make microwave popcorn without making a dent in my three batteries over a weekend.

PV sure would be nice if I ever did something stupid and needed a week to get recovered.

 

[Ramblinman]

I really wish I had the time to spend camping to really worry about power. As it is now I can run heater, freezer and make microwave popcorn without making a dent in my three batteries over a weekend.



Wow! I may not even need solar... What kind of batteries do you run?

 

[leadsled9]

I really wish I had the time to spend camping to really worry about power. As it is now I can run heater, freezer and make microwave popcorn without making a dent in my three batteries over a weekend.


What set up do you have that allows the microwave use? Are you using an inverter? If so...how big is the inverter? How big is the microwave? Where did you mount the microwave in your Hawk?

 

[pods8]

Wow! I may not even need solar... What kind of batteries do you run?


I already tried to highlight this point to you, a decent sized deep cycle battery will cover a couple days (even with a compressor fridge) in most situations, add in a second battery and you're probably good for a week. So if you're thinking that will cover your camping needs then no you wouldn't "require" solar. It certainly helps to have it but I'd spend the money sizing your battery bank properly first.

Mainly depends on how you're camping. Assuming you don't run other power hungry stuff then for 2-3day trips a single good sized deep cycle will likely handle things. 7 day trip then a dual battery set. Thus generally most folks won't require power sources. After 7 days you'd want to start thinking about recharge options (solar, generator, running the truck, etc.) The perk on solar is IF you have sun then it'll either recharge the batteries continually or at least limit the overall draw down if it's not quite matching up. So on regular trips you'll probably hardly cycle your batteries at all (longer life then too!).

My stance for most folks that aren't doing multiweek trips is to size the battery bank for what you need it to do w/o outside input. Then if you add solar on you'll only be improving your situation by keeping those batteries closer to full, if not totally full. However when the sun goes away for days during foul weather you're still good to go with your properly sized battery bank.

I'm running 210ah of battery, at this point in my life I'm never going to be out longer than a week (unfortunately), I have zero concerns about running my ARB fridge, LED lighting, and fantastic fans over that period of normal use on battery alone. However I just ordered up 100watt panel for the reasons stated above and because they're on sale so I got a panel & controller shipped for under $200. Hard to complain about that in my mind, I'll have a little more cost for mounting/wiring supplies when that part factors in but still quite tolerable in my book.

 

[Ramblinman]

Thank you for pointing that out. Sometimes I need someone to pull out the hand puppets for me Part of my thought process here also is to get done now what I would likely get done later. With this in mind, I am thinking of getting a controller and monitor installed at the factory ... and use the solar panel in a portable capacity which should allow me to direct the panel towards the sun or keep it out of shady areas. It would also allow me to nix it when I am going on shorter trips.

What I do not want is to have to start doing mods on the roof later when they could be done at the factory ... properly.

This said I am a little concerned about leaving camp to do the things I like to do (Hunt Fish Hike) and leave an attractive item like a solar panel out for the unscrupulous to acquire. So there is some benefit to having it permanently mounted.

This may be moot point though if I get two solid batteries which you are saying should allow me to go a week with a compressor fridge?

Comments?

Back to raking the leaves ... ugh ... they just keep coming!

 

[pods8]

This may be moot point though if I get two solid batteries which you are saying should allow me to go a week with a compressor fridge?


Here are the temperature conditions and voltage readings of running my ARB fridge for 6days sitting in my closed up camper to get an idea how it might perform for me, sorry no amp meter to get readings (but I might buy one soon and will post up results if so). http://www.wanderthewest.com/forum/index.php?/topic/4958/

In that type of weather I'd only be using my fantastic fan some and some lighting at night, neither that intensely so I'd have no concerns about making it a week with my battery bank. If you want to run flood lights to light up your camp at night or some other notable power draw then you might start having issue. If I was out winter camping and running the furnace a lot while having the compressor fridge in the heated camper so it was fighting against that as well I could see probably being reduced down from a week but I'd just be speculating on how long.

Use the info to make your own choices. I know I don't NEED solar but for the sale price I opted to grab that 100watt panel to help reduce battery cycling and to keep the batteries conditioned while sitting at home (batteries self discharge while sitting).

 

[Kodachrome]

At least have the roof pre-wired for a 100-135 watt panel, it is better to have it than not.

 

[Ramblinman]

At least have the roof pre-wired for a 100-135 watt panel, it is better to have it than not.


I am working with FWC to see if we can get the set up you recommended ... I will keep you posted!

 

[Ramblinman]

At least have the roof pre-wired for a 100-135 watt panel, it is better to have it than not.


Does anyone know if FWC would have to use different wire for the panel ... They typically wire for the 80W that they offer OR could they simply use two strands of their factory wire and put it to the same outlet.

Trying to make this system work.

Any help is appreciated. Sorry for all the dumb questions. I am truly the unknowing in this regard.

 

[pods8]

Does anyone know if FWC would have to use different wire for the panel ... They typically wire for the 80W that they offer OR could they simply use two strands of their factory wire and put it to the same outlet.

Trying to make this system work.

Any help is appreciated. Sorry for all the dumb questions. I am truly the unknowing in this regard.


I'd guess they're running 14ga off hand, you can call and check (I definitely wouldn't go smaller than that personally). The more amps you run the more loss you get but we're not talking huge numbers. For a 135watt panel putting out 17.2V running 15' to a charge controller in 14ga wire you'd get about 3.5% drop, in 12ga wire you'd get ~2%. Either way you should fine. But I'd definitely make sure they run a positive and negative wire the whole way and not use the frame as a negative.

 

[leadsled9]

Here's a tip for you guys getting the solar wiring done to prepare for a solar install down the road.

Make sure you specify that FWC locates the wires on the roof top and terminates them with their waterproof solar connector. Otherwise....you won't know where they terminate on the roof and have a heck of a time finding them. Don't ask how I know this. With the waterproof plug in place it's a simple matter of just plugging into the connector when you want to hook up your panel. The other end of the wires terminate under the cabinets.

 

[White Dog]

Been away for a couple of days. This has been a busy thread with lots of interesting discussion and some pretty strong opinions. Here's my two-bits.

I have done the Snowbird thing for a few years, living up to 4 months in our 24' travel trailer. We have both a 160 w solar panel and a Honda EU2000. For storage, we use 2 Trojan T105 6 VDC batteries in series and the whole mess is managed by ProSine 2.5 inverter/charger. I have remote management panels for everything, so I get a pretty good idea of what is going on. We occasionally use the microwave and regularly watch movies on a small very efficient LED TV. We don't ever use the A/C. With this setup in Arizona in the winter, we almost never worry about electricity. About once per week, we will run the Honda while we watch a movie just to top up the batteries.

Here's what I've learned.

1) A really good high output charger and a good solar controller are invaluable. They allow the batteries to take a maximum charge and also prevent damage. I have the ProSine throttled back to 80 amps maximum charge which is a touch under the maximum Trojan recommends for my batteries. I have never seen a charge rate over 65 amps even when the batteries are low and of course the charge rate tappers off as the battery approaches full charge. This powerful charger lets me put a lot of charge into the batteries quickly and safely.

2) Using a DC amp meter (a pricey but certainly useful tool) to actually measure consumption is the best way to see where the power is going. Sometimes its interesting. I was surprised to see how much power the solenoid in the gas fridge was using.

3) Spending a bit more money on a good high quality generator like a Honda is worth it. They are reliable, efficient, and quiet. Two details here. First, the Honda EU series inverts DC into AC which is very clean, cleaner than you get from your utility at home. I've seen a professional measure the quality of the power. It's impressive. I'm sure other makes are as good but all my 35 year of using generators have been with Honda and the total number of problems I've had is zero.

4) I was surprised how little power came through the 7-pin plug on the back of my pickup to recharge the RV battery. On the Dodge (when it worked at all - another story) it was about 10 amps. On my brother's 2004 Tundra it is about 12. On my new Tundra it is about 13 amps but I really haven't had a chance to test it fully. Ask me next spring. At these rates, it takes a lot of driving to recharge the RV batteries if they are low.

5) My insurance company loves my Honda generator. It gives me backup power to run my house sump pump during a power outage (when I'm home ). This is the main reason we went for the Honda EU2000 rather than the EU1000.

So which is better in my opinion: solar or generator. Neither. They each have their advantages and disadvantages. Sometimes I leave the generator at home but I'm sure glad I have it when I need it. Similarly, I suspect the first addition to the FWC when it comes next spring will be a solar panel. I just think I can do it a bit cheaper than the FWC option.

Long winded I know but hey, I've been away for a few days .

 

[craig333]

What set up do you have that allows the microwave use? Are you using an inverter? If so...how big is the inverter? How big is the microwave? Where did you mount the microwave in your Hawk?


1500 watt inverter. 600 watt microwave. Built a cabinet for it. And let me be clear, its a big drain. I don't use it for over five minutes at a time. Won't be cooking a roast or anything. Popcorn though

Camper has a marine optima. Truck has two Sears Platinums.

 

[Kodachrome]

I'd pay FWC or in my case ATC an extra couple hundred for them to come up with a rooftop wiring ferrule system in which we can swap solar wire out as needed. Otherwise put 12 gauge in there for a nice 120-135 watt and be done with it.

 

[Gerdo]

1) A really good high output charger and a good solar controller are invaluable. They allow the batteries to take a maximum charge and also prevent damage. I have the ProSine throttled back to 80 amps maximum charge which is a touch under the maximum Trojan recommends for my batteries. I have never seen a charge rate over 65 amps even when the batteries are low and of course the charge rate tappers off as the battery approaches full charge. This powerful charger lets me put a lot of charge into the batteries quickly and safely.



Remember that your charger should not exceed ~1/4 the amp rating of your batteries. (ie, 20 amp charger on a 80ah battery) This should be considered the max. This would recharge that battery in 4 hours or less depending on it's discharge state. Slower charges are better on batteries.

 

[pods8]

Ah, that is a big 100 watt panel, the one I linked to is 21" x 40" and under 15 pounds, killer for rooftop stuff.


Update, I weighted the panel I got on my bathroom scale. Alone it read 19lb. When checking my weight verse my weight with me holding the panel to see if the low weight reading on the scale is very accurate I got 19.4lb. So lets just say 20lb to be on the safe side it seems as opposed to 25lb (that was the shipping weight in packaging it seems).

 

[n0izh]

This has turned out to be an interesting thread! Lots of point counter point info. Here is my two cents. We have 330 amp hour (3x110) AGM batteries coupled with a 90 watt solar panel. The controller is a basic Morningstar. We run LED lights, an Engle front load fridge, stereo, LED TV/DVD, laptop computer(x2), and a much used Ham Radio(about 20 amps on tx). For heat we use a Wave6 most of the time instead of the forced air furnace. In the summer time even with several days of clouds there is enough light to keep the batteries charged at 90% and will hold that. In full sun the batteries are topped off by noon. In the winter with full sun the batteries get to about 90% to 95% charge after an overnight draw down to about 85%. For several cloudy days inn a row we start to see the overall net charge going down. We can go a week or more before the batteries are down to about 11.7 volts. As a result for winter camping we bring along the Honda generator which we plug in a Ham radio 30 amp swithed power supply for charging the batteries. My AGM batteries are a commercial style and handle the 15 to 20 amps I limit them to getting just fine without getting warm or venting gas. This is much better than the 8 amps DC the generator puts out on its own, and I don't have an on board charger in the camper(yet).
My solar panel is mounted flat on the roof, but I am considering changing that to be able to tilt it to better the sun angle. I'm sure that would just about cure my winter discharge trend, but have been lazy. The Honda fits perfectly under the couch, and when the temps are cool we never smell gas(not so good in 110 degrees). The added benefit of the generator in the winter is holiday left overs. We have a tiny microwave that makes warming up the Turkey and Ham easy for the wife, and gets me off the hook with the BBQ grill!

John