In short, the working principle of feed-in tariff means that you are paid for the excess electricity that is injected into the grid from the solar photovoltaic system because you do not use the excess electricity at home. The electricity retailer will pay you according to the electricity price listed in the contract you have signed with him. Therefore, it is necessary to select online suppliers reasonably.
In fact, there are two working modes of feed-in tariff 
1. The working mode of net feed-in tariff: You can get paid from the electricity generated by the solar system and injected into the grid. Therefore, if your system generates too much electricity to pay, you only need to save monthly electricity bills.
2. The working mode of the total on-grid electricity price: This is the old electricity price and no new connection is provided. In this electricity price, you will be paid for all the electricity generated in the working area of the solar system, because all the electricity you generate will be Pass your house and inject it into the grid, so you can benefit from the entire solar power generation. On the other hand, you will pay the electricity bill separately (electricity for your household appliances/equipment).
First, you need to check all online suppliers in the solar system work area, determine the best online supplier, and then start signing the feed-in tariff. Of course, you will know exactly how much electricity you will get for every kilowatt-hour of output.
Tariffs for each online supplier will be different. For each online provider, you must study its advantages and disadvantages. Before deciding which online provider to work with, you must weigh all the points. In addition, you may need to check your local online suppliers from time to time to see any tariff changes that may occur, as you may consider changing online suppliers to get the best tariffs. Definitely not only choose any feed-in tariff.
Before proceeding, you must research and weigh the different tariff preferences of online suppliers.
