Grid-tied, on-grid, utility-interactive, grid intertie and grid back feeding are all terms used to describe the same concept – a solar system that is connected to the utility power grid.
Advantages of Grid-Tied Systems
1. Save more money with net metering
A grid-connection will allow you to save more money with solar panels through better efficiency rates, net metering, plus lower equipment and installation costs:
Batteries, and other stand-alone equipment, are required for a fully functional off-grid solar system and add to costs as well as maintenance. Grid-tied solar systems are therefore generally cheaper and simpler to install.
Your solar panels will often generate more electricity than what you are capable of consuming. With net metering, homeowners can put this excess electricity onto the utility grid instead of storing it themselves with batteries.
Net metering (or feed-in tariff schemes in some countries) play an important role in how solar power is incentivized. Without it, residential solar systems would be much less feasible from a financial point of view.
Utility companies are required by law to buy electricity from homeowners at the same rate as they sell it themselves.
2. The utility grid is a virtual battery
Electricity has to be spent in real-time. However, it can be temporarily stored as other forms of energy (e.g. chemical energy in batteries). Energy storage typically comes with significant losses.
The electric power grid is in many ways is also a battery, without the need for maintenance or replacements, and with much better efficiency rates.
Additional perks of being grid-tied include access to backup power from the utility grid (in case your solar system stops generating electricity for one reason or another). At the same time, you help to mitigate the utility company`s peak load. As a result, the efficiency of our electrical system as a whole goes up.