An off-grid solar energy system is not connected to the utility grid, whereas an on-grid (also known as grid-tied) solar energy system is connected to the utility grid. Whether off-grid or on-grid system will establish your access to electricity, what equipment is needed for excess production.
When it comes to installing a solar power system, there are a lot of decisions to make. And because you’re investing in equipment that will last several years, you intend to make the right selections.
By partnering with the crew from National Solar Network they will be able to guide you through these decisions to get you the perfect system for your situation. However, doing a little homework on the front end can’t hurt either. That’s why we’re sharing the four differences between on-grid and off-grid solar power to help you choose.
The Differences Between Off-Grid and On-Grid Solar Energy
Difference # 1: Your Access to Electricity
Power Access with Off-Grid Solar
What is meant by off-grid solar systems? With an off-grid solar system, you’re completely reliant on the sun and power saved in batteries.
If you opt for a solar system that is not tied to the electric grid and you do not have a generator, you will only have electricity at 2 points:
When the sun is shining and your solar system is generating electricity.
When you’re pulling power previously generated by your solar system from a solar storage device, like batteries.
If you do not have batteries or a means to store your energy, you will have much less or no electricity when it’s cloudy, and you will not have power during the night.
With an off-grid system, you will not have access to additional power if you require it. What you are generating and what you have saved is all that’s there to power your equipment.
Power Access with On-Grid Solar
If you choose to install an on-grid solar system, you will constantly have access to electricity (unless the grid goes down), whether your solar system is producing or if you have batteries.
If your system is not producing any electricity or not producing enough power to power the devices, lights, machines, etc that you’re using, you can draw energy from the energy grid to supplement it. This ensures you constantly have sufficient electricity for what you need.
Difference # 2: What Happens to Excess Production
Excess Production with Off-Grid Solar
Depending on the size of the system you install, how much power you use, and when you use that electricity, there will likely be times when your system is generating more electricity than you’re using. What happens to this excess energy depends upon the equipment you install.
The majority of off-grid solar systems are designed to generate a certain amount of “additional” electricity in the daytime. The power stored in those batteries can after that be accessed when the system is not producing, like in the evening or throughout cloudy weather.
Depending upon your energy goals, systems can be sized to generate sufficient excess electricity in the daytime to cover your whole power usage all the time.
However, regardless of even the very best and most accurate estimates, the weather is unpredictable. If you experience abnormally over cast weather several days in a row, your system may not have the ability to produce adequate power.
While having extra batteries provides peace of mind and can offer a bank of stored electricity just in case this happens, they’re also pricey. Buying more batteries than you need may be cost-prohibitive, depending upon your budget.
Excess Production with On-Grid Solar
Just like off-grid solar, many that choose to install an on-grid system intend to cover 100% of their energy usage. This can be attained with on-grid systems also.
Depending on the time of day you use power, your solar system can generate excess power. As opposed to sending it to batteries as you would in an off-grid system, you can send it to the grid and you will be made up for that electricity.
Grid-connected solar power has an unique advantage over off-grid systems because net metering and other compensation methods from utility companies provide what is basically cost-free storage.
Difference # 3: What Happens When the Grid Goes Down
Power Outages with Off-Grid Systems
Your solar system is functioning separately from the power grid. If there’s a bad cyclone or event that knocks out the power, your solar system can carry on running. You will not notice differences in your service or access to power.
Power Outages with On-Grid Systems
By connecting to the grid, you get access to electricity whenever you require it. You’re also subject to some guidelines. If you have a grid-tied solar system and the grid goes down, you will not have power, unless you opt for a grid-tied solar system with battery backup.
Why is this? The shutdown of solar systems when the grid goes down is required by law. This is for the safety and security of power company employees who are fixing the high-voltage line.
While this is a disadvantage of grid-tied systems over off-grid systems, if keeping things up and running during a power blackout is necessary to you, then you may be interested in adding batteries to your grid-tied system.
Difference # 4: How You’re Billed for Power
Power Bills with an Off-Grid System
If your PV system is not tied to a grid, you will not receive an electric bill at all. And even with no electrical bill, off-grid systems are usually a lot more expensive because of the added equipment.
Power Bills with a On-Grid System
If you choose a On-Grid system, you can still see a few minimal costs on your power bill.
One type of cost you might continue to see is the service fee or delivery charge. This is the expense levied on consumers for connecting their residence or company to the grid. For many utilities, this fee is a flat rate that is not impacted by the amount of power you use.
Another type of cost you can see is demand charges. Demand fees are typically levied on commercial residential or commercial properties and are the raised electric rate you pay for the power you use during a peak demand period. The peak demand duration is generally the 15-minute period in which your company uses one of the most electricity.
Because using a large amount of electricity at one time places a strain on the grid, the energy will charge a higher rate for the power used throughout that period.
If your peak demand period is throughout the day, you may have the ability to minimize it with solar. As energy generated by your system will make up for some of the energy you use from the grid. If you pay very high demand fees, you might also want to check out peak demand shaving.
Hybrid Solar Energy Systems
A hybrid solar system also has a battery bank to save extra electricity. Hybrid systems, though more pricey permit their owners to maintain the lights on when the grid goes down.
While there stand out differences between off-grid and On-grid solar systems, the one that is ideal for you is dependent on your situation. Off-grid systems allow for complete flexibility from the energy, yet they’re often extra expensive. On-Grid systems marry substantial power financial savings with grid-backed dependence.