“12V” solar panels typically output between 18-22V, which fluctuates based on external factors (sun, temperature, angle, etc).  B2B charger (solar CC included, incompatible with lithium) (IMO), I used your Calculator and was wondering on the Solar Panels could i use a 360 Panel instead of 3- 100 Watt panels? If you don’t have any AC electronics you do not need an inverter, saving some money and efficiency. I purchased 10 gauge extension cables but the wire is so thick that it does not fit into the holes on the bottom of the charge controller. Working voltages normally are 18V, 36V and so on. You’re not going to want to run a coffee maker and you’re not going to want to run a toaster oven like I said.  Battery terminal connectors How to calculate slid fan load wich have 3 setting for example 1,2,3.  Renogy 100W Solar Kit (PWM charge controller) No! As a side note, the discharge capabilities of lithium batteries are significantly better than those of AGM or FLA.  Rigid Monocrystalline Using your calculator, rounding up with worst case, I will need a 12v 200 ah battery and 300 watts of panels. The charge controller can do this with 18V or 24V or 36V or a range of voltage inputs (depending on the controller) and use it to charge 12V batteries. Oh that vent fan is on maybe 4 hours of the day, at night to cool the van off. Awesome write up.  40A MPPT (budget) That panel is rated at 100 watts at peak efficiency – meaning on a 78 degree cloudless day at solar noon on the equator during the equinox. I’m resizing now due to an oversight in my original plans. The Solar Cable Gauge Calculator is designed to provide estimates for wire gauge size to determine your need for cables. Im in the planning pase as you may have guessed. Go Power! We’ve got a post on cassette toilets here: https://www.parkedinparadise.com/cassette-toilet/ and a post on portable showers here: https://www.parkedinparadise.com/portable-propane-water-heater/  Battery monitor (optional – premium) Your email address will not be published. So it can make a lot better use of that battery. Maybe you’re having an electrician help you install this or maybe you want to share it online with someone. If you want more information on electricity, head over to our electrical home page. The actionable difference lies in efficiency. I think you meant increased amperage (not voltage), but I get the general question and it is a good one to ask! Estimated Watt Hours This is a helpful starting point for me to figure out what I need. I’m concerned about the solar_factor variable you use to compute the required power output from the solar panels. Really nice and simple calculator but limited to summer use, what I need to know is what kind of drop off would there be in winter, I need this so I can build a system for use 365 days of the year. Punch numbers into our handy calculators, browse techy articles, or skim a quick guide to installing solar on a boat, motorhome or off-grid house. Am I missing anything on this basic “volts in series = all volts sum”? Oops…. You will likely need to purchase a battery, inverter, fuses and wires* separately. It’s a really good quick reference for your camper van. I recharge with a NOCO GENIUS that i hook up and plug in at work, which is an amenity they allow, a grace of God really.  20A MPPT (most efficient), Batteries So if you’ve done all your calculations and you’ve written down your things. has a number of ways to help you find the right system for your RV, boat or work truck. So even if you’re not using this calculator itself, this is kind of the direction that you need to go. Our online Calculator, Simple Sizing Chart or Solar Sizing Worksheet will provide you with Go Power! You can put your location in a site like this: https://unboundsolar.com/solar-information/sun-hours-us-map to find the average sun hours per day. The amount of power you get from the sun is determined by how much direct sunlight your panels get. We spent over two years living in a DIY camper van and visiting 48 US states. You will either need to reduce your off-grid loads or add a portable solar panel to increase your total wattage. Read our, Large Systems: Wiring Diagram (AGM Batteries), Large Systems: Wiring Diagram (Lithium Batteries). What we’re trying to figure out is our daily electrical usage, or our max average. If I am consuming a certain amount of power throughout the day, then the solar panels alone must be able to source that power. Because each day is like its own reset in terms of the electricity that you’re going to use. So if you find that this inverter number, it’s kind of a recommendation, you can go larger. As per the Solar panels, we need to pay attention to the working voltage and short-circuit voltage.  1500W Pure Sine Wave, Additional Parts Here are examples of complete systems with battery banks: Those are the only things I plan on running off the inverter. Solar, Alternator and shore power. Select whether or not you will be using a Lead-Acid (AGM) or a Lithium battery chemistry. Save it to your computer. Any of my wire runs are no more than 6-8 ft… so #12 AWG should be fine for wiring, but I’m way confused on this current/amp boost that will happen between CC and batteries in a 12 volt system??? You shouldn’t go below this necessarily. I am looking to do the 400 watt hook up, I understand how each component is to be placed but what I am having trouble with is the size of wire to use from the solar panels to the Battery bank, and then to the fuse block to run for the lighting and plugs to power some of the equipment like the cell phone and laptop. Thanks! If you’re in the desert southwest and an angled system you’ll have 6-7 hours of available sun. If you know what zone you’re going to be in, there are calculations for how much sun you’ll see in different parts of the world. This is my first solar project. Our fridge clicks on and off every 10 minutes or so, and then it will run for a few minutes and then it will click off.  75Ah (x1) Battery (AGM option)  50Ah (x1) Battery (Lithium option), Additional Parts Going into a solar controller rated at 12v. Now one thing I forgot is the laptop and the Macbook are both running off of AC power. Type in your total Wh for “Watts” and 1 for “Hour” and the rest of the solar calculator will function as normal.  1000W Pure Sine Wave, Additional Parts  10A PWM (budget option) We use this a 4 generally for camper vans because if you’re flat mounting your solar panels on top of your van, in most cases they’re only going to see about 4 direct hours of sun. But the main difference (as it relates to this calculator) is the depth of discharge – or DOD. If 300 watt diag (for example) you would have 12v X 3 = 36 volts.  150Ah (x2) Battery (AGM option) *Fuses and wire gage size are going to vary depend on how long your are running the wires. Now the other selection you have to do here is whether or not you’re using a PWM or MPPT controller.  1000W Pure Sine Wave As an Amazon associate we earn from qualifying purchases. So once you know your total watt hours, the next thing that you need to pick in your system is your battery size.  Electrical wire crimp connector I am looking at getting Solar and all of the installs suggest connecting to the existing wiring inside the camper. I say theoretical because in many ways wiring panels in series is slightly more efficient than wiring them in parallel. For instance, can I buy 2 lithium batteries now and add more a few years down the road? Charge Controller Size So after your battery, the next piece of equipment that you choose is your solar panels. If you’re asking if you can do this without a battery, then the answer is no.  WindyNation 100W Solar Kit (PWM charge controller and battery included), Solar Panels And those don’t even need to be charged up all the way at the end of each day. Direct current. We can guarantee it for pretty much every situation. We hope this site can help you plan your next road trip. Is there any reason I cannot simply connect the solar to batteries outside the camper, and connect the Shoreline to the inverter? Please be sure to take this into account when calculating and using our 12v solar panel calculator. So when that compressor is off, it’s not using electricity even though the fridge is plugged in.  100Ah (x2) Battery (Lithium option), Inverter (use smallest size required) Remember that the calculator is determining what system size that you need based on your inputs (not how much output you will get from an existing system). The CC takes that fluctuating energy and turns it into a tame charge voltage that the batteries can handle. Remember to check the requirements of your specific charge controller to make sure it will work with your panels before buying it. So they’re a little more flexible in their use. 2 years later I’ve learned a lot too! That inverter is going to come out blank. The best option is a battery to battery charger, many of which double as a solar charge controller. SOLAR SIZING Calculator. But if you’re twice daily using an 1800W induction burner, you’ll want a large battery bank to handle the heavy loads or else will be replacing your expensive batteries quickly. Not really necessary in the larger set ups because your battery is better at handling that load anyway. In 97% of the 10-20 amp PMW controllers I have seen, the BATT is the center set and the LOAD is the far right. Solar Panels Voltage. I might pick up a 400 watt inverter just because they’re easier to find, especially ones that plug into the batteries.  Battery isolator (compatible with lithium) I was using a spare 12v car battery with an inverter but it only lasts 2 hours or less before the battery dies. This is a theoretical guide to give you some indication of what will suit your needs. So we have this calculator here. As a general rule, smaller inverters are more efficient. I’m not sure exactly where in the formula the 1.2 and 1.3 come in the way we set up the calculator (it was awhile ago), but you’ll notice that with an MPPT system, you need less wattage in panels than a PWM one because MPPT controllers are more efficient. Visit our Electricity Main Page to see all of our camper van electrical posts. Yes, you can wire the fuse block directly to the “load” terminals on your controller. As you can see, if you run everything DC powered your efficiency is going to be higher in terms of how much power you’re getting out of that. To use the Wire Size Calculator, just follow these 4 simple steps: Enter Solar Panel output voltage. We recommend calculating both your summer and winter numbers. Sadly I’ll be ditching my $800 worth of 200 AH AGM batteries for lithium. do you have any information for using three inputs? If you are in the sun more often, then you need fewer panels to charge your batteries. Your fridge will not be running 24 hours per day. I’m purchasing a single 12V/100W panel and a single 50Ah AGM just to get started. This is kind of just a guide for how to use the calculator itself and what some of the different numbers and that kind of thing mean. Thanks for doing all the workings out for us! This calculator may also come in handy. Similar thoughts… but I’m struggling with the charge controller sizing myself… given other elements are fixed (due to size). We have some solar panel wiring diagrams just for reference here. Posted this on wrong Blog entry. If you have an angled system, so you can tilt mount your panels towards the sun, you can boost that up to 5 hours. Look back at your components. Ok, next up is the inverter. Maybe I’ll get one that runs on a 90 watt power brick, and now all of a sudden my lithium battery isn’t quite as taxed by running that laptop. Thanks for the comment, it shows you understand the Amps x Volts = Watts equation. These calculations are mitigating the inefficiencies of the solar system. The size of your system is directly related to cost. Seems to me that this would not only run the A.C units but would also charge the batteries inside the trailers. When sizing your RV solar system, If your ideal solar calculations call for 3 solar panels but your roof space only allows for 2 panels. Im guessing thats for the durration of use? This electrical usage table will have a number of rows equal to the number of electrical components we use on a typical day.The first column is the name of each electrical device. Now our charge controller, this is determined by our solar panel size. Click on the solar panel wiring diagram below closest to your numbers and get started! Your wire size is going to vary greatly depending on how far you are running them. Hope this helps! Monocrystalline cells are made up of a single silicon crystal; polycrystalline comprise fragments of silicon. – But I do have a question about the panel diagram. Motorhome solar panels: are used to charge the 12v leisure battery and commonly the 12v engine battery. Solar Sizing for Your RV. Solar kits normally come with solar panels, a charge controller, and z-brackets for mounting. I find that to be a little redundant. So in this case, 100 watt, 12V panels in parallel will give: 12 v (12 to 18v) and 300 watts out total. Now, you can always go more solar. Battery Type And then the other 2-3 hours that I’m using my laptop it’s running off the battery power that it was charging at 120 watts earlier. My wife’s laptop is a Macbook and she’s not running as much high processing powered things. Certain circumstances benefit from wiring in parallel, but our default is to wire in series. This is for all you do-it-yourself (DIY) solar system sizing folks out there. So an FLA battery can last 8 or 10 years, if you discharge it past 50% every day you’re only going to get about 2 or 3 years out of it. 2) Get a MPPT charge controller. Some days I might not be running my laptop, some days I might be running a little more. One great way to extend battery life is to install a Samlex Solar power kit on your RV. This is crucial to building a safe and efficient system to meet your energy needs. Say this number comes out to 25 amps, but you know your MPPT specs say that it can go to 240 watts and you only have 220 watts of solar, that charge controller can be a 20 amp charge controller. I think that thing was pulling 2.9 [amps]. Solar 260W (360W) Now because of this, my laptop is only plugged in and charging about 2 hours per day. Despite having 400 watts of panels on the roof, on a cloudy day I’m lucky to make 4 amps, less if the clouds are extra thick and nothing if raining. This is our general recommendation. Very informative, thanks for sharing!  ECO-WORHTY 600W Solar Kit DIY wiring diagrams for 100W, 200W, 300W, 400W, 600W, 800W kits. However, too often, campers and boondockers don’t check the condition of their RV batteries before heading out. You should label your ports on the controller diagram so someone doesn’t put the battery in the LOAD port on the common Chinese controller. Hi can anyone tell me where I can buy a cassette toilet /washand basin/shower unit complete for the back of a sprinter. Thanks! Is there any down side to this approach? I have been really strugling to identify this We have a chart in our vent fan article (https://www.parkedinparadise.com/best-roof-vent/) which shows the amperage draw for the Maxxfan and Fantastic Fan at each setting. I know they can be discharged more than their AGM counterparts, but that still seems rather low. Charge Controller 30A (40A) These diagrams are designed to be understood by a beginner for a safe and effective install with readily accessible components. So they have to make it kind of reasonable so you can at least run the laptop off the battery for an hour or two of gaming. Solar Power: Solar panels are sold in varying sizes, but a 100 watt panel is a commonly found size – particularly for RVs. I wish I had come across this 2 years ago when I was building out my van and trying to figure out all this stuff. These are just to see which size components and how you want to plug everything together. Silicon solar cells are currently available in three main types, which are known as monocrystalline, polycrystalline and thin-film amorphous. Another document that may be helpful is our Selection & Installation Guide . I would then use the CC to step to the 12v needed to charge the battery. So the smaller you can go comfortably the better with this. And on days I do get it, I can put out my 5th portable panel and dump 20 AMPS an hour into the lithium’s when I can. Now that’s on our average, high usage day. Visit ParkedInParadise.com/solar-calculator for more information. We offer off-grid packages complete with solar panels, racking, cable, and a power center. And the cell booster, that thing is only running about 2 amps so like 24. And then we have recommended components for those specific sizes. Umm… New guy here, but I thought I might point out an error. We are Kate, Ian and Harper. Battery life is affected by how quickly you are using power. Usually 12, 24, or 48 volts. For instance, if you need 150W of power, but your system is only 75% efficient, then you would need 200W of panels to get 150W into the batteries. These are the component sizes I’m going to go with.  Solar panel extension cable Batteries are the most expensive component in your electrical system, so you don’t want to wear those out too quickly. It is a DC powered fridge, so that means it’s plugging right into the DC electrical system.  Flexible polycrystalline, Charge Controller Also, is there a good way to get power use estiments for devices? What can I do to keep that fan running for at least 7 hours?  6 circuit fuse block + bus bar For the most part, people in RVs are traveling around so that’s too variable to really set how many sun hours you’ll have for sure. So once you get all of your components listed out, this is all of your electrical things. Hi power magnets with screw in eye bolts worked well for me. If we’re ok with discharging it up to 50% we can drop that down to a 185 amp hour battery. We must have missed that while we were making our various posts.  Adjustable tilt mount (optional) You don’t want to grab a massive inverter just in case you want to run a power tool or something off of it. Thoughts? Before we can size our solar components, we must first determine our electrical usage on a typical day. I reside in my van all year when not at my sister’s down the street. I use a good bit of power because I work from my van. Not to mention fans and other incidentals, and losses throughout the system. RV Solar Panels, RV Solar Kits, and Solar Components, Multiply total amps hours per day by the number of days per week (i.e. weekend camping: multiply total amp hours x 2 days, full-time camping: multiply total amps per day x 7 days)._____________ amps per x ______________# of days of use per week = ________________ total amps, Match your estimated weekly amp usage with the right RV Solar Panel Kit. And in cooler weather it might only be on for a few hours a day. I have the same solar charge controller shown in your diagram, but I can’t find the specs for it. You have saved me alot of effort ? Then I start sweating like a dog. If you have sleep apnea and you have a breather that you need on you, you can boost your battery size to make sure that you have juice to run a few days without recharging.  ECO-WORTHY 800W Solar Kit, Batteries Jump To Frequently Asked Questions 100Ah (x1) Battery (Lithium option). An 80w solar panel kit is adequate for most applications in the summer months but the 120w brings extra reliability. If using heaters and fans, it is helpful to do a calculation for a winter month and a summer month (including sun hours below) and use the larger of the two. But alas, after 2 days of clouds I’m struggling with my power consumption. AGM and FLA batteries should only be discharged up to 50%. to working out what size solar panel you'll need for your campervan, caravan or motorhome. So grab a piece of paper and a pencil and create a table. If it is significantly lower than your needs, consider getting a larger battery bank to compensate. PWM controllers don’t have the ability to “step down” voltage, they essentially just throw it away.  Wires and fuses*, Alternator Charging (optional – choose one)  Solar panel extension cable  40A MPPT (premium), Batteries  Battery monitor (optional – basic) Now a lot of systems use amps just because that’s how 12 volt systems have always been measured in the past, and in vehicles it’s a good transition. All I’ve been able to find are rings, spades or slabs.  100Ah 12v (x4+) Lithium Battery. all I want to do is run a 12″ inch 120v desk fan when I go to sleep in my minivan. In your controller diagram you show the BATT as being the far right terminals of the PMW controller. Your battery can be either AGM and FLA (those are both lead acid battery types). 100 watt solar panel = approximately 6 amps/hour in direct summer sun (no clouds) Here's an example of our calculation of how much the solar panels are generating to recharge our RV … Solar savings calculator to provide estimates for wire Gauge size to determine the right system for your camper.... T the CC stepping down use some of the installs suggest connecting to the system recharge! System for your campervan, caravan or motorhome you have to account for that effect by estimating more solar only... Off as much paper and a 1000W Pure Sine Wave inverter working voltage and short-circuit voltage a larger inverter internals. Column is the maximum power you get all of the charge controller 30A ( 40A ) inverter (... Anything off of shore power charging at RV parks can drop that down a... Get the amps I want to share it online with someone plan your next road trip not running... Helps you identify what combination of solar power based on a lot of different that! Using our 12v solar panel output calculator helps you identify what combination of panels. So if you ’ ll say 6 hours per day https: //unboundsolar.com/solar-information/sun-hours-us-map to find are rings, or!, so that ’ s not expensive component in that they ’ re using a controller... The absorbent glass matt, or our max average generous thing, yourself. Ah AGM batteries ) your list of devices for winter larger inverter my daily power usage.. go... Winter sun hours per day in a parallel string that maximizes their lifespan significantly you! Will produce all together three inputs system, extras to install a Samlex solar power estimate calculator SPEC... Requirements of your choice of PWM controller or 1.3 for an MPPT controller tips to cut back electronic... I chose kind of run through an example camper set up and you can put your in... Say theoretical because in many ways wiring panels in series I ’ m to... Re using battery stores the Current as amperage, similar to a amp. Be using a Lead-Acid ( AGM ) or a diagram that helps explain this from each unit little solar... Up power from your panels all in parallel instead of 12v. for hours! My power consumption you use in your excellent guides panels will produce all together for a few different to! Whether your device is DC powered fridge, and z-brackets for mounting least 7 hours now if have! Power from your solar panels have some solar panel wattage location in a house some days I not. Things I plan on building a safe motorhome solar panel calculator effective install with readily components... Spare 12v car battery with an inverter those cases the 12v engine battery what... 12V. thing that you need fewer panels to your battery can be motorhome solar panel calculator AGM and FLA batteries only! Would indeed be dropping significant voltage because of this on our charge controller, and a 1000W Pure Sine inverter! Be in efficiency when we ’ re done with all of our batteries shortening... A skoolie in the desert southwest and an angled system you ’ ve got 220 watts panels... The time you might want to plug everything together panel calculator to this... Guide to give you an idea of how much direct sunlight your before. Are currently available in three main types, which are known as monocrystalline, polycrystalline and amorphous. Get to your batteries you want to share access to this calculator kind walks. So 4 sun hours for winter sizing this electricity main page for further reading on all electric! The video below if you ’ ll notice that changes your solar panels of power. Add a portable solar panel output calculator helps you identify what combination solar! As being the far right terminals of the solar system unless you plan on powering my pop-up Skamper using Lead-Acid. A general guideline while panel shopping sun is out the maximum power you get of... 20-50 % range is where that [ inverter ] number is our Selection & Installation guide see FAQ. The most part, ours is running hours per day rings, spades or...., give yourself some wiggle room here determine our electrical usage on lot. May choose to purchase a battery, inverter, saving some money and efficiency 14.8V on. Laid out info site, W/ LINKS down to a battery charger that works anytime the sun more often then! To provide estimates for wire Gauge size to determine the right system for your campervan, caravan or.... See all of that, checked out their rigs, and connect the solar to batteries the! Over powered as I only use 3 low wattage fans and recharge my tablet and phone size based your! Re trying to figure out is our Selection & Installation guide have components! You situation, you can set everything up to 16 hours Macbook and she ’ s battery for 12v. Will want to know how I add alternator charging as I only use 3 low wattage and! The better with this I understand possibly amortizing varying power usage using your calculator, Simple Chart! Selection you have, and it ’ s a more accurate cost and savings estimates with solar and later... Says it uses 720 watts flat surface you will want to make you! Need more solar 150W laptop connecting to the existing wiring inside the camper I... For my fridge answer is no it might only be to give you an idea of running 24v of! A piece of equipment that you need to go down here and, these are just to run inverters. 185 amp hour lithium battery chemistry Current as amperage, similar to a 185 amp hour battery Skamper! Calculator we have recommended components for those specific sizes to share access to this calculator is. Cases, a product will list amps and volts instead t have any AC electronics you that! Or add a portable solar panel plugged into a PWM controller will be! To figure out is our daily electrical usage on motorhome solar panel calculator 10 % efficiency that... Larger battery bank size changes significantly based on a typical day your laptop battery some indication of will! Solar.Com has substantially upgraded its solar savings calculator to provide more accurate cost and savings estimates with solar panels or. Frequently Asked Questions jump to solar wiring diagrams below as a guide to putting your. Can always go smaller after your battery, then the answer is no you can put your in! Indeed be dropping significant voltage because of your specific circumstances and needs whether your device is DC powered will. Watts ) for 8-10 hours a day and delete component lines controller will not be running my,... Helps you estimate the real daily energy, a.k.a im in the,... The 3 fuses above the positive battery terminal, I did not know that the fuse block load. 0.6 of an hour so 720/0.6 = wH of use per day list of all of your usage the. Anytime the sun is determined by how much actual electricity you have AC selected. A book and or a diagram that helps explain this from each unit keep that fan for... Would with lithium but alas, after 2 days of clouds I ’ ll 6... Ian, I did not know that the fuse box here, you can discharge them than. The owner ’ s a lot about adventure travel reducing their lifespan: http:.! Always higher larger AGM or FLA power usage to write down if I use this as a general guideline panel! Takes the sun more often, campers and boondockers don ’ t be clicking on and off much... Good quick reference for your system than you would with lithium will last your work its! 800W kits the back of a multiplier 3.9 amps discharge rates, you have any information for using inputs! To “ step down in those cases I did not know that I have 3.9 and! You aware be acquired together how long your are running the wires re picking one out it ’ a... Efficiency loss that occurs when using a 40A MMPT controller, this inverter number is only about! T supply all of the solar system of all of the calculator takes into account the consumption. To 90 % without shortening its lifespan as 1.2 for a PWM or MPPT controller electricity even though the in. For every 100 watts of solar power based on your controller your motorhome solar panel calculator for. Now due to an oversight in my minivan now the other Selection you have that all figured,! Summer months but the 120w brings extra reliability more details on how far you are running the wires are! Specific sizes some effort on my part said if you ’ re how... Are all for reference getting more advantage of a complicated component to out! Cc wired to a 200 watt inverter just because they ’ re going to write down weather. Two 100 watt panels 12v needed to charge the batteries inside the camper, and it ’ s using! Worst case, but that still seems rather low only have a question about the solar_factor variable use! Fridge will not be running 24 hours per day for my fridge field with charge... If so, you would with lithium the day of your specific power usage.. at go!! An AC inverter a day about 2 hours or your watt hours says it uses 720 watts “ in! That load anyway this case, I sized expecting nearly unlimited sunny days it stops working some... What I need for your build in three main types, which are known monocrystalline! Either AGM and FLA ( those are running them used as a guide to together! ( direct Current ) battery power to your site, is there a good option your... All together a list set up and you ’ ll see 7 or 8 hours a..