You have more than one and you want to know how many amps do 2 100 watt solar panels put out?. You are not being greedy having more than 1 solar panel ha ha . This is because you know the more amps you can produce the faster your battery will charge.
I mean who wants to wait for hours and hours while your battery charges. You can’t wait that long if you are out in the wilderness on a camping trip. Plus the extra amps will allow you to charge and use the battery at the same time.
So let’s take a look at the number of amps those 2 100 watt solar panels will produce
How Many Amps Do 2 100 Watt Solar Panels Put Out?
“ Different 100 watt solar panels put out slightly different maximum amps. So for arguments sake we will assume a 12 volt panel that puts out 5.38 amps. Having the panels connected in parallel means that the 2 100 watt solar panels will put 10.76 amps (max)”
How did I arrive at that 10.76 amp figure?
According to HES PV Canada’s solar electric specialists;
When wiring solar panels in parallel, the amperage (current) is additive, but the voltage remains the same. (Source HES PV)
So that means if each 100 watt solar panel produces 5.38 amps you multiply by 2 equalling 10.76.
At this point I have taken the liberty of producing a table. It shows the total amps of 100 watt solar panels connected in parallel using my 5.38 max example.
|Number Of 100 Watt Solar Panels||Amps||Total Amps Put Out|
|2 x 100 Watts||5.38A||10.76A|
|3 x 100 Watts||5.38A||16.14A|
|4 x 100 Watts||5.38A||21.52A|
|5 x 100 Watts||5.38A||26.9A|
|6 x 100 Watts||5.38A||32.28|
How Do I Find Out How Many Maximum Amps A 100 Watt Solar Panel Produces?
There is a theoretical formula you can use to find the maximum amps a 100 watt solar panel will produce. The maximum power rating which is 100 watts needs to be divided by the panels maximum power voltage (VMP)
“What is VMP?” I hear you ask. Solar Mango says;
Voltage at maximum power(Vmp) is the voltage at which maximum power is available from a photovoltaic module. Most solar panel manufacturers will specify the panel voltage at maximum power (Vmp). This voltage is typically around 70 – 80% of the panel’s open circuit voltage (Voc) (Source: Solar Mango)
The VMP can usually be found in the manufacturer’s specifications or on the rear plate of the solar panel. For our example we are going to use an imaginary figure of 18.6 VMP.
So the formula in this case would be 100 ÷ 18.6 = 5.37A. Isn’t it miraculous that that happens to be the figure I have used for maximum amp output? Ha ha
By the way, A reputable manufacturer would have the maximum amps a solar panel would put out. Printed in the panel specifications on line, in the instructions or on the rear of the panel.
Are There Other Ways To Find How Many Amps A 100 Watt Solar Panel Can Put Out?
The number of amps a100 watt panel puts out at any given time is dictated by weather conditions. For instance under full sunlight you would expect the panel to achieve the full 5.37A or close to it.
But what about if there is a haze or a bit of cloud about? This will affect the amps produced. How do you measure that?
Using A Digital Multimeter and Ohm’s Law
Ok don’t be scared and stop reading my post because I have mentioned Ohm’s law. If like me you were averse to all things to do with physics at school. This will not be painful because I am not going to go into a long winded explanation you won’t understand !!!
You will only be using the Ohm function on the multimeter. This is because the voltage needs to be divided by the electrical circuit resistance.
So using the multimeter the number of volts the panel is producing needs to be measured. In this case we will use a hypothetical number of 17 volts. Then we need to measure the electrical circuit resistance (Ohms). We will use an imaginary figure the meter gives us, say 3.9 Ohms.
We now divide 17 volts by 3.9 Ohms this equals 4.36. So the number of amps the solar panel is putting out is 4.36A.
If you are interested in an indepth look at how to do this.
2 100 Watt Solar Panels Set Up In Parallel
It is not advisable to measure the number of amps a solar array is putting out using a multimeter. This should be done by an expert or somebody who knows what they are doing. Because you can damage the panels.
However you know how many amps one panel is putting out at any given time. Because they are connected in parallel 2 100 watt solar panels should be double the output. 4.36 x 2 = 8.72A
How Many Batteries Will 2 100 Watt Solar Panels Connected In Parallel Charge?
This can be worked out with this simple calculation of sun hours multiplied by amps. We know that 2 100 watt solar panels connected in parallel put out 10.76A (max) per hour. The average amount of sun hours in the height of the summer is 6.
I know many other sources of information say 8 sun hours. However the sun is at its strongest between 11 am and 4pm. Before and after those times of day it is weaker. So erring on the side of caution I believe 6 hours is a better number to use.
So multiplying 10.76A by 6 sun hours equals 64.56. This means that a battery can be recharged by 64.56Ah per day. If you insist on pushing the sun hour boundary to 8 hours. Because you happen to live in a very sunny climate it would equal 86.08Ah.
But I believe that for those of us living in the north of the northern hemisphere we should use 6 hours.
What Amp Hour Batteries Could 2 100 Watt Solar Panel Array Comfortably Charge?
If you have lead acid batteries you can only discharge them to a maximum of 50% of their capacity. Anything more than that will permanently damage them. So this solar array is probably capable of keeping 2 x 100Ah or 1 x 200Ah batteries charged.
LiFePO4 (Lithium Iron Phosphate) batteries can be discharged by 90% without any ill effects. A 100Ah battery taking into account being used while charging would be ideal.
Pushing the boundaries of battery charging potential using solar panels is not a good idea. You really want to keep it within the bounds of real world use rather than theoretical. Theory is great but reality could mean a flat battery when you really need it’s power.
If you want to know more about LiFePO4 batteries.
My Closing Thoughts
Under certain circumstances it is worth having 2 100 watt solar panels connected in parallel. Because the array will put out double the amps. If we take a quick look at what a 200 watt solar panel produces in terms of amps. It can be as high as 11A plus.
At this point you might be thinking why bother with 2 100 watt solar panels connected in parallel. When a 200 watt panel will put more amps out on its own. I suppose it depends on your situation and use. This could be the case if you are installing panels to a vehicle or boat.
You might feel the weight of a 200 watt panel or 2 is too much. So you opt for 2 or 4 100 watt flexible panels.
If you would like to know more about 100 watt solar panels. You can take a look at my review here;
I hope you enjoyed this post and have found it helpful. If you have any questions about How many amps 2 100 Watt solar panels produce?. Or want to leave your own personal review, please feel free to leave a comment below.