RV Photo voltaic techniques may be something from a single panel you purpose on the solar whilst you’re parked someplace, to a dozen or extra panels mounted to your roof. How a lot photo voltaic is the correct amount? Sizing your RV Photo voltaic system correctly can prevent money and time in addition to be sure your system performs as anticipated. This text is targeted on determining simply what number of photo voltaic panels you want.
RV Photo voltaic System Sizing
Folks have instructed us their solely massive street block to getting a system, just isn’t realizing how a lot photo voltaic they want. I’ll even admit I didn’t know both, and bought an multi functional package that works nice, however isn’t fairly as massive as I wanted. You may learn my evaluation of that package right here.
It doesn’t matter in case you’re dwelling the Van Life or RV Life or rocking a College Bus Conversion, the best way you decide the dimensions of your system is identical.
Step one is to learn the way a lot energy you’re going to be utilizing. That is essentially the most tedious half, but in addition crucial. It’s essential add up the whole electrical energy used from each equipment you’ve gotten. The best means to determine the whole energy is to transform your whole calculations into watts. Don’t fear, there may be a simple means to do that too!
RV Photo voltaic Energy Math
Your entire main home equipment can have a sticker on them someplace that claims what number of Amps its attracts and what number of Volts it runs on. For instance, we have now a residential fridge in our RV and contained in the door I discover the ability ranking sticker under.
Right here you see that our fridge runs on 115 Volts and attracts 3 Amps. To transform this to watts, we use the system AMPS x VOLTS = WATTS. So doing 3 x 115 = 345, we all know that our fridge is utilizing 345 Watts per hour when it’s operating. I determine the fridge is barely really operating half of the day, and in standby mode the opposite half, so we take our Hourly Wattage (345) and multiply that by the Run Time (12) per day and get 4,140 Complete Watts Per Day.
Simple proper? Now we simply have to do this similar factor for all of the home equipment in your RV, and write it down, so we will tally up the whole watts per day for all of them. As soon as we have now a complete wattage for all the things we’re going to be operating in our RV, then we will transfer on to the subsequent step, which is selecting a sort of battery to retailer our RV Photo voltaic Energy.
Flooded Lead Acid
In relation to RV Batteries there are 3 principal varieties you need to select from. The commonest one, and the one that’s most probably in your RV from the manufacturing facility, is a Flooded Lead Acid (FLA) Deep Cycle.
It’s much like the battery in your automobile, however designed to have the ability to drain down earlier than being recharged. The FLA model of battery is able to a 50% discharge with out damaging it earlier than it must be recharged.
A FLA Deep Cycle is sweet for a mean of 5 years earlier than they have to be changed. Whereas they do have the bottom up entrance prices, they do require some upkeep to maximise their life span. After a mean of 200 discharge and recharge cycles, a FLA battery will begin to have a decline within the quantity of vitality they’ll retailer.
FLA batteries additionally have to be in an exterior compartment, and that compartment must be vented to the skin air. Through the charging cycle they produce gasoline emissions that would kill you if they’re in an inside space of your RV or Van.
AGM Batteries
The following sort of battery is named an Absorbent Glass Matt (AGM) Battery. An AGM battery is a sophisticated model of the usual FLA Battery. One main attraction to them is that they’re utterly sealed, so there isn’t a hazard of battery acid being spilled out of them.
AGM Batteries are additionally upkeep free and final on common twice as lengthy than an ordinary FLA Battery. On the up entrance price they’re going to price 20 to 50 % extra per battery relying on the dimensions of the battery.
LiFePO4 Batteries
The final sort of battery is a Lithium Iron Phosphate (LiFePO4). That is thought of to be the holy grail in RV Photo voltaic techniques. A LiFePO4 battery may be discharged 80 % with out lack of energy or doing harm to the battery itself. Most LiFePO4 batteries will final by way of 5,000 charging cycles.
At a charge of 1 cost cycle per day with a photo voltaic system, it ought to final you round 12 years in your RV. One other benefit to the LiFePO4 is it could actually deal with a lot bigger sustained energy utilization than its lead acid counterparts. If you’re planning on operating an AC unit along with your photo voltaic system, that is the best way to go.
The LiFePO4 does have the best up entrance price, at a mean of three occasions the value of a FLA battery, nonetheless they’re additionally just one third the burden. Relying on the dimensions of your RV Photo voltaic system you might want a number of batteries to retailer the ability, in order that weight can add up quick.
How Many Batteries?
Upon getting determined which sort of battery is one of the best match in your price range and energy wants, the subsequent step is to determine simply what number of batteries you want. For this we’re going to consult with the Complete Watts Per Day from step 1. So let’s imagine that after you added all of it up, you bought a complete of 10,000 watts per day.
You may convert the Amp Hours of the battery you select into watts utilizing the identical system to maintain all the things simple. For this instance lets assume we’re going to use a 200 Amp Hour LiFePO4 battery. So doing our math of 200 Amp Hours X 12 Volts = 2,400 Watts.
With a view to run all the things for twenty-four hours with out a recharge, you would wish 5 batteries. In order for you to have the ability to run all the things for 48 hours with out a recharge, you would wish 10 batteries. You’re solely restricted on the variety of days you go by your individual price range and out there battery house.
Many RV Photo voltaic professionals suggest having the ability to run for 48 hours on battery energy alone in case of foul climate.
How Many RV Photo voltaic Panels Do I Want?
So right here is the place the mathematics will get slightly tough, however not inconceivable. It’s essential know the way a lot Peak Solar you’re going to get every day to cost your batteries again to 100 P.c. Close to the equator you get extra, close to Canada you get much less. We’re going to use Common US Irradiance of 5.3 to assist determine this one out. Since we’re going to be touring in every single place, the quantity will change anyway based mostly in your location.
To learn the way a lot Complete Photo voltaic Energy you want, you divide your every day want by the 5.3 common Peak Solar time. Utilizing our 10,000 watt instance from above, we divide 10,000 by 5.3 for a complete of 1,886 Watts Of Photo voltaic Panels Wanted. To offer your self a cushion, and make your math simpler, spherical it as much as 2,000 Watts Of Photo voltaic Panels.
There are a number of mixtures you are able to do to attain the two,000 Watts you want. You are able to do 20 One Hundred Watt Panels. Or you are able to do 10 Two Hundred Watt panels. You are able to do 5 4 Hundred Watt Panels. You see what I’m getting at.
The approximate RV Photo voltaic Panel measurement is 2 Toes by 4 Toes. How a lot out there roof house you’ve gotten, will decide how manel panels you’ll be able to really match up there, which is able to inform you what wattage you want. For instance, say you’ve gotten sufficient room on the roof of your RV to solely match 4 panels. With a view to get the wanted 2,000 watts, you would wish 4 500 Watt panels.
What Measurement Photo voltaic Cost Controller Do I Want?
The reply to this query will rely completely on the Photo voltaic Panel Voltage, Photo voltaic Panel Wattage, and in case you plan to wire your Photo voltaic Panels in Sequence, Parallel, or Sequence-Parallel. Your finest plan of action is to ask your RV Photo voltaic vendor what gauge wire you’ll need to go from the roof of your RV, which means the panels must be wired collectively, and which of their cost controllers mates with the remainder of the system one of the best.