You don’t ‘need’ a consumption monitor in order for your solar power system to work. It will produce exactly the same amount of power with or without one, but that power may not be put to the best use. It’s kind of like driving blind.
You’ll save more money in the long run if you have a consumption monitor. Your inverter provides only basic data of power produced by the system – not your consumption.
A consumption monitor fills in the blanks by comparing solar power production with your electricity consumption. This tool goes a long way to solving the conundrum of quantifying your power usage, leading to better economic outcomes for you.
Plus, it may come with a fancy app that you can play with and show off.