Good morning, Dawn Michelle; 

Very well done.  You are getting into consideration of just some of the additional things that are included in the current outline for this subject. 

Yes, the weight of the panels is also something to consider.  My Winnebago Elandan has a suggested total weight limit of 150 pounds for anything going up onto the roof (and it is a good thing that I am in that weight range for going up the ladder onto the roof), and there is also the GVWR or Gross Weight Vehicle Rating to be considered when adding more things to the motor home.  When I weighed my motor home the first time, I realized that I had only 760 pounds of "cargo" weight that I could put into the motor home for a trip.  With the normal suggested weight allotment of 175 pounds per person, two people comes to 350 pounds right there,  That leaves only 410 pounds for stuff.  If I fill the fresh water tank with 54 gallons of water, that is 448 pounds of water, and I am 38 pounds overweight right there.  

So what happens if I want to carry some clothes or maybe food in the refrigerator and in the cupboards?  It only gets worse.  I did check the rated capacity of the axle assemblies, the rims, the tires, the brakes, and other parts, and concluded that they are rated to carry more, and I had to make some serious changes in the rear suspension to get my GVWR up to where I can carry the things needed for any reasonable trip.  The really odd thing is that the changes made in the back are a Regular Production Option (RPO) that Winnebago had available, and they also gave you a higher rated GVWR placard with that RPO installed. 

Anyway, I calculate that now the Winnebago Elandan is good for about 16,000 pounds, or just a little more than about 1000 pounds than it was originally.  I will not need to add that much more weight for my purposes, but it is good to have that level now.  It does seem that there are so many things to consider when trying to do almost anything with one of these vehicles. 

With those considerations in mind, that is one of the reasons why I chose and bought some SoloPower flexible silicon cell solar panels made on a thin stainless steel substrate.  They are much lighter and thinner than the more common aluminum framed solar panels, so that helps with both the wind resistance and also the weight, because the 70 Watt panels are only 3 pounds, as opposed to about 18 pounds for a similar aluminum framed panel, plus there is the additional weight of the mounting hardware and framing to get them up off the roof surface.  But I do not like idea of drilling holes in the roof for mounting the solar panels.  That is another reason why I chose the thin SoloPower panels.  They literally will be glued to the roof using a thick layer of sealant.  That takes care of the wind resistance and the hole drilling problem, but it does bring up another problem; the lack of air space behind the solar panels.  That is one of the compromises that I am making; accepting that the panels will be getting hotter during the day and their power output will not be a good as it would with air space behind the panel for better heat dissipation and cooling.  If I want the low profile and the low wind resistance, that is one of the factors I must accept as part of the overall package.  While I am putting a rated 270 Watts of solar panels on the roof, I am actually expecting only about 200 Watts of electrical power from the system under normal conditions.  Engineering is always a series of compromises.  

If I can find additional panels of the specified size needed for the remaining space available, I can add about another 100 Watts to the system, and having about 350 Watts of solar power would really be nice.  There is another solar panel maker who did have panels of about the size needed, but they are also very expensive at around $10 per Watt in comparison with the SoloPower panels I bought.  $10 per Watt is like prices from back around 1990.  I bought most of my eight Solarex MSX-60 panels in the late 1990s when they were about $5.00 per Watt.  Today many solar panels are commonly available in the $1.00 to $1.50 per Watt price range, and in quantity they are less.  In a pallet quantity, they can be down around $0.50 to $0.60 per Watt.  Container quantities are even less. 

Also, your idea of using the solar panels in a "portable" configuration is quite workable.  I have done that for many years with three Solarex MSX-60 aluminum framed 60 Watt panels for operating the portable radio station out of the Subaru.  For supporting them at the chosen angle, I use adjustable "trekking poles" to hold them up, and I move them about every hour or so to face the sun as it goes across the sky.  For the current coming from each panel, the length of the wire and the wire size is somewhat "generous," but it does work.  I have also carried them in the Winnebago Elandan between the beds in the back bedroom for portable operation of that radio station under the Elandan side awning on the folding table for display and demonstration purposes. 

Time for another cup of coffee. 

Enjoy; 

Ralph,  Latté Land, Washington 

   I'm thinking of buying some new solar panels for my house to charge batteries when the power is out.

Looking for the best deal.

Hi Ralph,

Just now found this group. I also have long connections to solar and wind energy systems, having been in the alternative energy business since 1980. I guess I'm pretty-much retired now but still do consulting work and some sales in both disciplines, but mostly in PV these days. I originally got involved in PV when I was a yacht broker in Santa Barbara in the 70's and rented a corner of my office to a guy named Matt Voore, who invented the solar powered cabin vent for boats that sat unattended for long periods.

I've designed a number of PV/inverter systems for RV's over the years and carry a pair of portable panels in my own RV, but the rated output is only about 80 Watts. I have a 200 Watt panel sitting in the garage awaiting the time when I get over my apprehension over making holes in the fiberglass roof. ;-)

I also was the wind department head at DC Power Systems in Healdsburg, Ca for 4 years and taught our dealer network wind technology and theory all over the country (and out of it), as we were importers and distributors for the best small wind turbines on the market at the time. I'll put my $00.02 in here and suggest that using a microturbine for RV use is essentially not worth the trouble unless you intend on staying at a very windy, fixed location for some time. This is because it takes a substantial tower and guywire installation to safely install any wind turbine - even tiny ones. Also, unless the hub is at least 10 meters (or 30') higher than the surrounding terrain (upwind of your rig), the output of the machine will be minimal and sporadic. Towers are THE big problem with all wind turbines, but especially small ones, because of the costs and installation requirements. It was this way when I got in the business 36 years ago, and it remains that way today.

The best option for most RVers, IMHO, is PV and a decent battery bank to store the energy. I use portable panels because it allows us to have solar input while having the RV parked in the shade, I do have concerns about havening them ripped off while out hiking, but we mainly stay in State and Federal Parks, so the security is pretty good. 

I hope this discussion takes off again as it's my main area of expertise.

Matt