solar energy system is one of the most efficient and environmentally friendly ways to power your home. Although you will have to handle considerable upfront expenses, with a PV system you will be able to save money in the long run by cutting down on electricity bills.
Types of solar systems: grid tie, off grid, hybrid
But there are a lot of things to consider before installing a solar system, and its tie to the local grid is one of them. While most homeowners settle on grid tie systems, you should carefully look into their pros and cons as well as research the alternatives. This guide is designed to give you some info about grid tie in solar systems and help you make an informed decision on whether or not to go with a grid tie solar system for your property.
First of all, let’s discuss what are the three main types of solar systems in terms of their relation to a local electrical grid, i.e. grid tie systems, off grid systems, and hybrid PV systems.
Grid tie systems: connected to the grid
Grid tie systems are permanently tied to the electricity transmission lines. Thanks to the grid tie, they can operate without a solar battery backup. Grid tie solar systems allow their owners to use solar power when needed, or to send excess power to the grid they are tied to.
Off grid: no connection to the grid
Unlike grid tie systems, off grid solar setups are designed for situations where there is no tie to the power grid. These systems rely solely on the energy generated by PV panels and need a battery bank to ensure a backup power source. Solar systems without a grid tie are better suited for mid and large households but must be properly sized to meet their daily electricity needs.
Hybrid: tie to the grid + power storage
Hybrid solar installations are tied to the utility grid just like grid tie solar systems. But unlike grid tie systems, they use special inverters and solar batteries to store excess electricity for later use when power from the grid is not available. A grid tie allows the owners of a hybrid solar system to draw energy from the grid when they use up all of the saved power, as well as send energy to the grid in case some of it is left after charging their solar batteries.
Advantages of grid tie solar systems
Grid tied system is cheaper to install
Grid tie systems are normally much cheaper to install than systems that are not tied to the local power grid. Firstly, they require no battery storage, which is the most expensive part of hybrid and off grid systems which can account for up to 40% of the total initial investment. While grid tie system installation cost net of the federal solar tax credit ranges between $15,000 and $30,000, a solar system that is not tied to the grid would typically cost $30,000-$70,000 depending on panel effectiveness and equipment needed. And as a bonus, grid tie systems are cheaper and easier to maintain than those having no tie to the grid.
Additional savings due to net metering
Secondly, with a grid tie system, you can save a lot of money with net metering policies which have been adopted by around 40 US states so far. Net metering is a mechanism that allows the owners of grid tie systems to sell excess electricity by sending it to the grid. This is a great way for households with grid tie installations to get credits from a utility company that partly offset the cost of their grid tie system’s initial investment. The credits can be used by grid tie system owners when they need to draw electricity from the grid, such as during periods of outcast weather when the energy their solar system generates may not be enough.
The grid serves as a virtual battery
Solar batteries used in systems without grid tie, besides being expensive, lose their storage capacity over time. Grid tie solar systems, on the other hand, can basically use the grid as a virtual battery that provides a source of backup power.
Disadvantages of grid tie systems
Despite all the advantages, grid tie solar systems have their drawbacks. The most obvious flaw of grid tie systems is the absence of a battery, which serves as a reliable backup energy source in installations that are not tied to the electricity transmission lines. The second disadvantage of grid tie solar systems is their vulnerability to power outages. Due to their grid tie design, solar energy output must stop during blackouts for safety reasons.
Key components of a grid tie solar installation
Grid tie solar systems require less equipment than those not tied to the grid. Let’s look at the main components of a grid tie PV system:
Solar panels are a key part f every PV system, and grid tie solar systems are not an exception. In both grid tie and off grid systems, solar cells harvest the sun’s energy and create an electric current, which is transmitted further to eventually power our homes.
A solar mounting system is a structure to safely fix the panels of grid tie systems on rooftops or ground.
Solar wires and cables
Solar wires and cables are used to interconnect the components of grid tie solar systems and serve as channels transmitting the electric charge.
Grid tie inverter
Grid tie inverters convert direct current (DC) generated by solar panels to alternating current (AC), which is utilized by the majority of home appliances. They also adjust the voltage of a grid tie system so that it fits the requirements of the utility grid.
Conclusion: grid tie solar is a cost-effective choice for your home
Now that you are better informed about grid tie in solar systems, it might be easier for you to decide which system would better suit your needs: grid tied, not grid tied, or hybrid. If you have a limited budget, grid tie installation is the best way to go solar. Grid tie systems require lower upfront investment and pay off faster, as you can sell excess energy generated by solar panels to your local energy grid.