DC Wattmeter using the LAN-Module controller
The LAN module controller can be used to measure the DC power. Check the idea in the application document.
More details about the LAN controller.
The logging of data from the LAN controller can be made publicly available by means of https://thingspeak.com web service.
Warning: Avoid any risks when working with the high-voltage DC ratings! Beware of the dangers of electric shocks or even death!