Living Off The Grid, Solar
So, are you tired of utilities and property owner taxes? Maybe you are just tired of paying 30 dollars to over night in an rv park. We have the answer here.Before I retired we tried to get the GMC set up so we would not need to park over night in an rv park if we did not want to. I bought every book on rv solar that I could find and asked everyone I thought might know, how to get started. There just was no simple "do it yourself" information out there. So, I did it pretty much backwards and wasted a few bucks. In the past I have posted simple solar here on the blog. But, for the life of me can not find it. There is no simple index to my posts here. So, I thought maybe we should re visit this topic.
Don't look too hard at the above photo or you will see that the painter let the clearcoat run. I just had this roof repainted. I was not as happy with the job as I was when the same company painted the Vdub. I paid 1 and a half times just to get the roof painted as I did the entire baja. Different topic for different day.
Don't buy the solar panels first. They need to come last, and I will tell you why:
A picture of the one on the rear. There are two more, hidden, for a total of 300 watts on our roof. This is a perfect setup for Teri and me. 250 watts would be fine if we wanted to tilt the panels, nope. So, I put an extra panel on to make up for the" no tilt".
This is where you start. Incadescent lights burn lots of energy. This one is an led. We have nothing but led lights in our coach. Leds have come a long way over the last couple of years. I even have led lights in our home now. The color is important to me. I think you can see that this particular light is not too cold.
Even though this photo is blurred you can see the light. It is a little strip that puts out about 220 lumens. Outfit you rv with good quality led lights, not the China ones on ebay. This light is put together in the Phoenix area and I sell them. Lifetime warranty.
Another obsticle we needed to overcome was our electric water heater. This on demand propane heater is perfect. Sips lp while it is on. I can't say enough about the on demand water heater. Before we installed it I had to fire up the Onan just to run the water heater. Regular propane water heaters consume a lot of gas. This thing is perfect. Cost less than 130.00 shipped to us in Arizona. Look at the fluorescent replacement leds to the left. These are bright.
While I don't have a picture, test the tv you buy before you buy it. We had a 3 year old flat screen that was using 55 watts of power. Found a new one that would use 25. Took my meter to Walmart, at midnight. Pulled ac lines and checked them til I found this one. Teri uses a computer monitor for her tv in the bedroom and it uses about 22 watts. Now, we run both on same power consumption as the older one we had, up front. I watch tv til after midnight most evenings so this was important for our setup. I normally turn off the inverter when finished watching tv so there is no draw from the set or the satelite receiver. Takes our receivers less than a minute to load all of the programming once they are powered back up. We use two inverters. I have a 700 watt one hooked to the tv system. We use it most of the time. Have a 2000 watt inverter for the vacuum cleaner, microwave, and hair dryer. Modified sinewave.
Another big power consumer is the furnace. The blower motor, on most, will draw 7 amps. We use a Wave 6 catalytic heater most of the time. It keeps us warm. Crack a window or roof vent. We turn it off when we go to bed and set the furnace on 60 degrees.
Ok now we have the rv set up to draw the least amount of power. Even bought netbooks that will run 6-8 hours on battery. Charge the batteries when sun is bright and maximum solar is available.
Look at the meters in the photo above. The one on the right is a must have. Get one before you buy solar panels. It is like a fuel gauge on your car. How do you know how much fuel to put in your tank, or take out, if you have no gauge. This particular one is a Trimetric 2020. I bought it new for under 150.00. It came with the large shunt so I can run anything through it. The unit shows now that I am down about 8 amp hours. We never plug the coach in while sitting in our driveway. It has been cloudy and the batteries are a bit down. One hour, or less, of sunshine, will charge them back up. Today is cloudy but by 2 pm I will still have enough solar charge to fill them up. I think the meter on the left is showing 2 amps of solar on the panels now. The meter on the right shows what is at the battery, not on the panels. Many folks use only a meter like the one on the left. That is not good enough. You must know what is in the battery, not on the panels. Either meter will show when solar is charging, or has been shut off, but only one like on the right is an actual fuel gauge. It will also show how much power any appliance in the coach is using. After I bought this meter is when I got rid of the fluorescent lights. They are also power hogs.
We use 4 6 volt batteries. They suit us just fine. 2 6 volts do not give us a large enough "fuel tank". Some need larger tanks to store more fuel.
The meter on the left is a remote meter for our charge controller, mounted close to the batteries. Get a charge controller large enough to handle your needs. Our's is 60 amp but 30 would have been fine. I got a deal on this one, new, for 110 bux. Whichever controller you buy, make sure it has adjustable set points. Charge controller is very important. On a good day when the batteries are down I see 14-16 amps on the meter, at the batteries.
Now, to the panels. It is very important not to let your panels get shaded. I measured our spots on the roof and bought panels based on their physical size. We rarely have a shade on any of the 4 panels.
Cables. You have to run large cables. How large? Depends on your system. I ran 6 gauge welding cables down from the panels to the charge controller and on to the batteries. Might have gotten away with 8 but nothing less. Consider the cables as a water hose. The larger the diameter the more "juice" that will come down to the batteries. The length of cables will also need to be considered. Longer the cables, bigger in diameter, they need to be.
There is a lot more that can be said about solar on your roof. I just wanted to give you something to think about. Panels keep improving and dropping in price. I may start replacing my panels in the future should I see something that suits me better. With what we have, Teri and I can pretty much stay anywhere we want for as long as we want with no electricity plugged into our coach. We have done this for over a month at a time with no generator. Set your rv up to consume the least amount of power and you will love this. I do not "rough it" well. I have the same toys in the rv that we have at home. I watch a lot of tv and use the internet, with a mobile router and aircard, as much as I want. We do not run the air conditioner. If it gets hot it is time to move. I bought only one new panel. The others were used. Even at the old prices I have less than 1500 dollars in our system. You can do it cheaper now. I love the fact that this works and I have no tilting of panels to do. I never think about this. We have power, always. It is a rare day when our batteries do not get a full charge.
I hope this might give you food for thought and save you a few dollars. Nothing technical here. Anyone can do this themselves. You need a drill and a wrench.
Oh yea, here are the new Justins.Have a great weekend.
Dan
posted by Dan & Teri Gregg @ 9:57 AM
9 Comments:
Good article, Dan. Your points make a lot of sense.
I have a question, you say the trimetric shows "The unit shows now that I am down about 8 amp hours." on my 2025 when the display shows the red minus symbol left of the display, that number is the draw in AMPS on the batteries after calculating the input from the panels while charging which your indicator displays.
Mine while charging without draw on battery the minus symbol is not lit.
Could it be the difference between trimetric models?
Mickey
I have a question, you say the trimetric shows "The unit shows now that I am down about 8 amp hours." on my 2025 when the display shows the red minus symbol left of the display, that number is the draw in AMPS on the batteries after calculating the input from the panels while charging which your indicator displays.
Mine while charging without draw on battery the minus symbol is not lit.
Could it be the difference between trimetric models?
Mickey
No, I have the meter in the "fuel tank" mode, my words. You will need to look at the instructions but by holding down the button it will go into another mode so you can read all kinds of things. This is a super little meter that takes a little bit of reading about. Took me a while to understand just what all it will do.
Dan
I read the manual for the 2020 which is the one you have, the closes I could find to what you say is the water tank analogy,but it still says :“Battery % full” and not AH left so what your display shows - 8.61 AMPS is not a % of full tank which is what I can't understand. What you state that you are down about 8 amp hours, assuming you have 400 AH storage, that would be only about 2% of your capacity which is possible depending time of day and what if anything is drawing from batteries. : Exactly how does the TriMetric do this measurement? The water tank analogy: Imagine a
water tank that is closed, so you can’t easily determine the level of water inside the tank-- but you can tell when it is full,
because then the water flows out of the top. This is analogous to a battery, because it is difficult to sense how much
energy is in a battery when it is partially full, but it is not so difficult to sense (using Volts) when it is full. Now, assuming
you know the total volume of the tank, when you withdraw water from the tank you could tell how much was left if you
precisely measure the volume of water that you removed from the tank, and subtract this, and when putting water back in,
add that back. This is analogous to how the TriMetric measures how full the battery is.
With everything off except the frig and gas monitor I have a 1.3 AMP draw according to my trimetric so for a 24hour period I will use 31.2 AMPS.
I'm still learning so this my thoughts.
ps (The difference on input from flat to tilt is an increase of 12 AMPS on my system)
Mickey
Dan
I was planning on doing this but this happened down in MS last week. I figure its totaled...
https://picasaweb.google.com/gmfoster/20111121?authuser=0&authkey=Gv1sRgCJ7pv96g1PuPswE&feat=directlink
Garry
This meter shows both actual hours in the hole and percentage. I don't care to watch % as I want to know how many hours I have left. If I get time I will run through all of the functions on this meter and post pictures on the blog. One must read the paperwork a few times to get things figured out.
Dan
You must put the meter into the correct mode to show this, along with several other readings.
email me if you need to.
gregg_dan at hotmail.com
Dan
You must put the meter into the proper mode. Email me if you need to.
Dan
gregg_dan at hotmail.com
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