Solar charge controller not reporting unused solar capacity

[Texican]

I have a 10kw gridtie and currently installing 12kw off grid. I have emporia vue monitoring the gridtie solar output by the second. my gridtie is using 240 watt panels and my offgrid using 250 watt panels, maybe I can compare output from gridtie per panel and can know almost exactly what the offgrid system should be able to produce if load called for it

 

[SolarHead]

I just discovered PowerView Pro (which works with Sol-Ark) has an API link to AmbientWeather , and they sell sensors.

Ambient Weather WS-2902 Smart Wifi Weather Station with WiFi Remote Monitoring & Alerts

Ambient Weather's best-selling Personal Wi-Fi Weather Station, the WS-2902, allows you to monitor your home and backyard weather conditions with a brilliant, easy-to-read LCD color display. Monitor indoor and outdoor conditions, including wind speed, wind direction, rainfall, UV, solar...

ambientweather.com

Not sure this is the exact solution but sure looks like it could be.

 

[wholybee]

Maybe use excess power to heat water, then measure the power consumed to do that? If you're already heating water, install a swimming pool

 

[labeeman]

I've wondered the same thing. Did I install too big of a solar panel array? For example, say I consume 2000 watts daily. But my array is a 10,000 watt array (capacity to produce that much). Sure, I could store a lot in a battery bank, but for argument sake or point of this question, lets assume my batteries are topped off at 100% SOC. The 10,000 watt array is not being used to its potential, right? Now, that's 10,000 watts based on the size of the panels (say they are 300watts each panel x number of panels = 10,000 watts, that's rated power). But, the sun , weather, clouds, my panels aren't able to make what the sticker on the back says they can make. So, I think I would need a sun irradiance sensor or meter installed somewhere out on my ground mount rack, near my panels, at top, middle. That sensor would report real-time what amount of sun is coming in, and based on size of panels what they would produce based on the amount of sun that's coming in at the moment (real time, updated every 1 second maybe). So, the sensor tells me what amount of power I SHOULD be able to make at the moment, which is not the amount of power I am using. The amount I am using is my load at the moment, it fluctuates of course, someone runs a light, a hairdryer, toaster, and the load changes all day long throughout the entire day. If I knew from the sun sensor mounted out at my solar panel array what my array COULD be making max at the moment, minus my current usage (load), then that difference would be what capability or power I have there that I could be using , but am not.

Does this make sense? I don't net meter (sell to grid). I am grid connected, but I like to use grid as last resort when my system cannot produce enough sun power to meet my demand. But it'd be nice to know, and report say over time, day, week, month, year of how much power I kind of let slip by me (without using it, or storing it in a battery). This data I think would be helpful. I would know if my array is over-sized, under-sized, and I would know if buying more batteries was a good idea or not, and I would also know how much extra unused capacity I have in my solar panel array to either buy another inverter (if the existing inverter is maxed out), or buy a water heater tank and pre-heat water so my tankless gas water heater doesn't have to work so hard (and use less gas in the process).

You would use a PYRANOMETER mounted at the same angle as the PV array.

 

[Checkthisout]

You would use a PYRANOMETER mounted at the same angle as the PV array.

ProWeatherStation, Data Logging, Wireless Solar Weather Center

www.tyconsystems.com

 

[efficientPV]

Batteries Not Included.......
Diverting excess power is not that hard, just look at the array voltage compared to the expected power point voltage.

This is an interesting video. 650W of panels at a small camp in Minesota in the winter providing 6 gallons of hot water and when that is up to temperature, excess power goes to a space heater. This system operates in parallel with charge controller off array DC voltage. Panels are kept at power point voltage for efficient transfer of power to heating element. Standard heater mechanical thermostat with arc interrupt so no damage to contacts. Thermostat (only one in this tank) was switched with an upper type and when temp is reached, power is sent to a 1500W space heater.

Camp is heated with propane to prevent pipes freezing. PV heating will save some of this expense. Diversion is proportional and when more camp items are turned on, less energy is diverted. This camp has a 12V lithium battery which never supplies power for heating and is always kept at full charge. Wall switch is a three way. In one direction it goes to the water heater and automatic diversion to space heater. Or in other position it only goes to space heater.

 

[Pernundle]

Excess solar power should be sent to the waste volcano.