Off-grid vs. Grid-tied Systems Solar Power Options

When understanding solar power options — off-grid vs. grid-tied systems — it helps to know how each type works and what trade-offs come with each.

If you’ve been contemplating adding solar power to your home or business, you've probably heard of grid-tied and off-grid systems. Both types use photovoltaic cells to turn sunlight into electricity.

Understanding Solar Power Options: Off-Grid vs. Grid-Tied Systems

The principal difference between them is that the first is connected to the local utility grid, while the second is not; the functional differences go a bit deeper. Here are the implications for choosing between these setups.

As a tri-state area leader in residential solar and commercial solar panel systems, TerraSol Energies has helped hundreds of homeowners and businesses navigate these exact choices since 2009.

What are Grid-Tied Solar Systems

Grid-tied solar systems capture the sun's energy whenever it's available. Because they're also linked to the power grid, however, your property can still receive energy from the utility company at night and on overcast days, or any time your energy usage exceeds the system's production.

A grid tie inverter handles this by converting the direct current (DC electricity) that solar panels generate into AC electricity your home can use, while keeping the system connected to the utility power grid.

Power can flow in both directions between your solar array and the utility grid, and if you generate excess electricity, you can sell it back to the utility company through net metering to reduce your electricity bill.

Some homeowners opt for a battery backup system alongside their grid-tied solar setup. This hybrid solar system stores excess energy locally and provides backup power during a power outage, without the full cost of a standalone off-grid solar installation.

What Are Off-Grid Solar Systems?

Off-grid systems must generate more power than grid-tied solar alternatives because their users don't have the luxury of switching to utility power when they need a backup power source.

These setups incorporate their own energy storage units in the form of battery banks, which can tide you over when the sun isn't shining sufficiently to meet your power needs.

A solar charge controller regulates the flow of DC electricity from the solar panels into the battery bank, preventing overcharging.

An off-grid inverter then converts that stored battery power into AC electricity for household appliances. In some cases, off-grid solar installations also include a backup generator for extended periods of low sun.

Off-grid systems are common in remote areas where connecting to power lines is either impractical or too costly. They offer complete energy independence from the utility grid, but they also require more careful energy usage planning.

Navigating the technical differences and utility policies of grid-tied, off-grid, and hybrid systems doesn't have to be overwhelming. At TerraSol Energies, we help you evaluate your property, analyze your long-term energy usage, and design a custom solar solution tailored to your exact needs. Ask our experts now!

Which Solar System Should You Choose?

While both types of solar panel systems require many of the same basic components, grid-tied systems are less costly to install, mainly because they don't include battery banks or charge controllers.

On the other hand, users of these systems have to pay for the electricity they obtain from the grid and are subject to the policies of the utility company.

Your electricity company might make it less profitable to sell back your surplus energy by modifying its net metering rates and agreements. Or it could demand that consumers jump through extra hoops and pay additional surcharges to connect their solar energy installations to the grid.

Off-grid solar systems are more appropriate for remote areas where the cost of running a transmission line (or power lines) to the property would be prohibitively expensive. They also makes sense in industrial settings that can provide their own backup power from on-site generators.

A hybrid system sits between the two — it stays connected to the power grid but also includes battery storage, giving users backup power during grid outages while still benefiting from net metering and lower installation costs than a fully off-grid setup.

Remember, though, that most off-grid users need to be more careful about their consumption habits. If you exceed the capacity of an unconnected solar energy system, you may not have anything to fall back on.

Ultimately, your choice of solar system should reflect your needs. Even more than installation cost, your long-term energy usage requirements and habits will be the most relevant limiting factors in your energy-generating future.

To learn more about the benefits of solar power and discuss the best solar system for your situation in Pennsylvania, southern New Jersey, or Delaware — and for further help understanding solar power options, off-grid vs. grid-tied systems — ask our experts today.

Frequently Asked Questions

Which is better, an on-grid or an off-grid solar system?

Your long-term energy usage and location dictate which is best. On-grid (grid-tied) is cheaper to install and provides the safety net of utility power, whereas off-grid gives you total energy independence but requires careful monitoring of your power consumption.

What is the major disadvantage of a grid-tied system?

The main drawback is that you remain subject to your utility company's policies. They can modify net metering rates to make selling back your power less profitable, or they can enforce new surcharges and connection fees.

What is the difference between grid-tied and grid-connected?

"Grid-tied" and "grid-connected" mean the exact same thing. They both refer to a solar system connected directly to your local utility company's electric grid, allowing power to flow in both directions.

Can I run AC on an off-grid system?

Yes, but you must be very careful about your energy consumption. Air conditioning uses a massive amount of power. Because off-grid systems rely solely on battery banks for backup power, running high-draw appliances like AC could cause you to exceed your system's capacity, leaving you without any power to fall back on.

What are the advantages of a grid-tied solar system?

They are significantly cheaper to install because they don't require expensive battery banks or charge controllers. Additionally, they allow you to automatically draw power from the grid at night or on cloudy days, and you can sell your excess generated power back to the utility company.