FilterGuy
Solar Engineering Consultant - EG4 and Consumers
Sorry, I am late to the party..... but let me throw in my 2 cents.
First: All Panels are rated at 'Standard Test Conditions' and very rarely actually produce at that level. Consequently it is no surprise you are not seeing the full panel wattage.
What the sales sheet says is "Flexibility for oversized PV array power ratings e.g. 7 kW or more" (Your 8030W falls into the 'or more'
)
That is saying it is OK to Over-panel just like you are suggesting. Just keep the Voc under the max. (This is very typical for an MPPT controller)
The Schnider controller is a good one, but it will 'only' charge the batteries at a rate of 100A. Since your battery is 48V, then the most you will get out of the controller is 48Vx100A = 4800W if the battery is nearly empty or 58.4Vx100A=5840W if the battery is nearly full
If you keep the Voc below the Limit for the SCC input but have more than 5840W coming from the panel, the controller will just not use the excess. However, as you are suggesting, adding more panels could still help ensure you get the max out of the controller more often. What would happen is that you would hit the controller max earlier in the day and stay there till later in the day. When it is cloudy you will get more production than you do now and in the winter you will get more production than you do now.
On a sunny day, if the batteries start at 52.8V you would see the typical power curve ramping up as if it was going to some high power number (say 7000W) but it would suddenly flatten out at 100A x 52.8V = 5280W and stay in that ballpark till either the batteries get charged or the sun goes down.
Conceptually it would look something like this:
This was my feeble attempt to show the curves and it is not completely accurate. The ramp would actually start at about the same time in the morning but ramp up much faster. In the afternoon it would stay at full power longer, ramp down quicker and stop at about the same time as without the over-paneling. This can give you 15%-20% more total production on sunny days. Things are too variable to make a prediction about cloudy days other than to say you will get more production.
There have been a lot of threads around this topic lately..... maybe I should do a resource explaining Over-Paneling.
First: All Panels are rated at 'Standard Test Conditions' and very rarely actually produce at that level. Consequently it is no surprise you are not seeing the full panel wattage.
What the sales sheet says is "Flexibility for oversized PV array power ratings e.g. 7 kW or more" (Your 8030W falls into the 'or more'
)That is saying it is OK to Over-panel just like you are suggesting. Just keep the Voc under the max. (This is very typical for an MPPT controller)
The Schnider controller is a good one, but it will 'only' charge the batteries at a rate of 100A. Since your battery is 48V, then the most you will get out of the controller is 48Vx100A = 4800W if the battery is nearly empty or 58.4Vx100A=5840W if the battery is nearly full
If you keep the Voc below the Limit for the SCC input but have more than 5840W coming from the panel, the controller will just not use the excess. However, as you are suggesting, adding more panels could still help ensure you get the max out of the controller more often. What would happen is that you would hit the controller max earlier in the day and stay there till later in the day. When it is cloudy you will get more production than you do now and in the winter you will get more production than you do now.
On a sunny day, if the batteries start at 52.8V you would see the typical power curve ramping up as if it was going to some high power number (say 7000W) but it would suddenly flatten out at 100A x 52.8V = 5280W and stay in that ballpark till either the batteries get charged or the sun goes down.
Conceptually it would look something like this:
This was my feeble attempt to show the curves and it is not completely accurate. The ramp would actually start at about the same time in the morning but ramp up much faster. In the afternoon it would stay at full power longer, ramp down quicker and stop at about the same time as without the over-paneling. This can give you 15%-20% more total production on sunny days. Things are too variable to make a prediction about cloudy days other than to say you will get more production.
There have been a lot of threads around this topic lately..... maybe I should do a resource explaining Over-Paneling.
