Why does my CC show that I produce more electricity than I am using?

[fcparks]

I have a Midnite Classic 250 and from my understanding the kWh reading on the homepage is how many kWh it is producing. However, its readings are more than what I am using. For example if I only use 1kWh the next day my CC may produce 2kWh of electricity. But my batteries can’t even take that much in? Am I misunderstanding this reading?

 

[LakeHouse]

from my understanding the kWh reading on the homepage is how many kWh it is producing.

This is a measure of how much energy (kWh) you've produced in the past. The Watts reading is how much power (W) you're producing right now.
If you make 1000 Watts (1 kW) of power for one hour, that would be 1kW * 1hr = 1kWh of energy.
So your Watts value will go up and down, but your kWh value will only ever go up because it's a cumulative measure of the energy you've produced.

 

[fcparks]

This is a measure of how much energy (kWh) you've produced in the past. The Watts reading is how much power (W) you're producing right now.
If you make 1000 Watts (1 kW) of power for one hour, that would be 1kW * 1hr = 1kWh of energy.
So your Watts value will go up and down, but your kWh value will only ever go up because it's a cumulative measure of the energy you've produced.

Ok. That makes sense, but how can my panels produce 3.6kWh if my batteries only need 1kWh to be fully charged.

 

[v_green57]

Ok. That makes sense, but how can my panels produce 3.6kWh if my batteries only need 1kWh to be fully charged.

This is a CUMULATIVE value, not an INSTANTANEOUS one. It "ticks up" since the last time you zeroed it. The manual should explain how to reset the kWh counter.

Think trip odometer on a vehicle.

 

[400bird]

On the midnite charge controller the kWh reading resets sometime between sunset and sunrise, so it's daily production.

How are you calculating daily usage? Are you including the idle draw of your inverter?

 

[JWLV]

Is anything ON and drawing power right now? The solar power generated is counted for both charging your batteries and powering whatever you have connected to your inverter.

For example, at night your devices might use 1kwh of power. During the day, it'll still use that 1kwh of power but not from your batteries. It'll be from your solar panels at the same time the solar panels are charging your batteries. So your solar panels will be providing 1kwh to your devices and 1kwh to your batteries. That's 2kwh. Also consider AC to DC and vice versa. You'll probably lose about 10-20% from that.

 

[fcparks]

Is anything ON and drawing power right now? The solar power generated is counted for both charging your batteries and powering whatever you have connected to your inverter.

For example, at night your devices might use 1kwh of power. During the day, it'll still use that 1kwh of power but not from your batteries. It'll be from your solar panels at the same time the solar panels are charging your batteries. So your solar panels will be providing 1kwh to your devices and 1kwh to your batteries. That's 2kwh. Also consider AC to DC and vice versa. You'll probably lose about 10-20% from that.

We have a Schneider Conext XW pro that reports our daily energy draw from the batteries. Maybe that doesn’t include power the CC is sending to the house, but it is wired through the inverter so I’m not sure. Like the last two days we used 1.8kWh but have produced 3.8 kWh.

 

[v_green57]

On the midnite charge controller the kWh reading resets sometime between sunset and sunrise, so it's daily production.

How are you calculating daily usage? Are you including the idle draw of your inverter?

Ah, didn't know that about MidNites. Good info.

 

[400bird]

We have a Schneider Conext XW pro that reports our daily energy draw from the batteries.

Wait, you have an XW and Midnight charge controller?

Post in thread 'Adding Schneider XW Pro' https://diysolarforum.com/threads/adding-schneider-xw-pro.19090/post-631072

Haha, I'm running the same set up

Maybe that doesn’t include power the CC is sending to the house, but it is wired through the inverter so I’m not sure. Like the last two days we used 1.8kWh but have produced 3.8 kWh.

Do you use DC power in the house?
I wonder if the 1.8kWh reported by the inverter doesn't include idle draw and inverter efficiency. I've never really paid attention to compare the two kWh numbers.