Grid Tied System
Deciding on the best setup for your solar installation might seem a bit daunting. Solora Solar is your expert guide, following industry best practices and customizing each install.
A grid-tied system is the most common and straightforward solar setup. These systems are typically installed on rooftops or ground mounts and are directly connected to the utility grid through the main service panel. They feed excess power back to the grid under a net-metering agreement with the utility company.
The net-metering is defined as access energy credit since solar energy is generated when Sun is shining but may not be used if there is no instantaneous load or consumption requirement. This energy can be feedback to the grid and “be stored for later use”. In reality, energy still be used instantaneously by Utility by supplying to their customer.
The Utility will provide access energy credit, usually 1:1 and that credit can be used on demand when there is Sun is not shinning. The payback is normally within 8-10 years by taking advantage of all the federal and state incentives available. The system can last up to 50+ years without any significant maintenance.
If you’re planning to increase your energy usage in the future such as EV charger, it is recommended to oversize the system 10-20% to accommodate.
There are mainly two major types of Grid-tied systems, in terms of choice of Inverter (convert DC power to AC), 1) String inverter 2) Micro-inverter, however, with new NEC safety Rapid Shutdown requirement, 90% of the roof mount residential system are equipped with either micro-inverters or optimizers. The micro-inverters and optimizer are connected to each module to control each module voltage and performance independently. The micro-inverter converts DC to AC energy, oppose to optimizer which reduce the DC energy for safety. Both micro-inverter and Optimizers provide additional critical function of mitigating any residual shading to increase system performance as well as module level performance monitoring, compare to String inverter, performance can only be monitored at String level, 8-14 modules connected in series, depending upon location without benefit of maintaining system performance in case of shading related issues.
System with micro-inverters and Optimizer are generally higher in cost due to additional component and labor, but these systems are easier to modulate for any future upgrade and addition or even to add battery storage.
Lastly, with new technology, the newly launched Enphase Micro-inverter IQ8 can be installed without battery storage with power still be available in case of Utility outage to provide Sun power during the day of outage, since this new micro-inverter can form its own grid.
