Solar energy has become a more and more popular choice for homeowners looking to reduce their carbon footprint and energy costs. When considering a solar system for a new house construction, understanding the key differences between on-grid and off-grid solar systems is crucial for making an informed decision.
Read this blog to understand on-grid vs. off-grid solar systems.
What is an On-Grid Solar System?
An on-grid solar system is also called a grid-tied system. This system uses PV panels to produce solar energy, and this will be directly connected to the local electricity grid.
It allows users to use solar energy in their homes or businesses, along with the on-grid for backup.
Here, surplus energy generated during daylight hours can be fed back to the electrical grid, often gaining credits through net metering programs. However, net metering application varies based on each state’s policy. In contrast, electricity is drawn from the grid during night periods of insufficient solar generation to meet the demand. A beneficial feature of this setup is its adaptability. This will ensure an unremitting power supply for the property, irrespective of solar energy production fluctuations.
The distinctive factor of this system is its needlessness of an energy storage battery, as the grid itself effectively serves as the energy reservoir, improving its cost-effectiveness and ease of maintenance with the support of energy storage solutions.
Advantages of On Grid Solar System
- Compared to off-grid solar systems, on-grid solar systems are less expensive, as they do not require batteries and other equipment.
- Net metering lets you use the extra electricity your solar panels make during the day to balance out the electricity you use from the grid at night or on cloudy days.
- The power grid acts like a budget-friendly and reliable storage system for your extra solar energy.
- You can earn extra money by selling Solar Renewable Energy Credits (RECs) in Indian areas like Rajasthan, where solar power generation is significant and where net metering or other mechanisms allow you to sell excess electricity back to the grid.
Interested in the broader benefits of renewable energy in construction? Discover how renewable energy is transforming construction projects.
Disadvantages of Grid-Tied Solar System
- If the main power grid goes down, your solar system will also stop working. This is done to protect utility workers from electricity flowing back into the grid while they are fixing it.
- Also, with a grid-tied system, you still depend on the power grid — you’re not fully independent.
What is an Off-Grid Solar System?
An off-grid solar system is a self-sustaining energy solution that operates independently from the public electricity grid. It consists of several essential components: solar panels to capture sunlight, a charge controller to regulate energy flow, a battery bank for storing excess power, and an inverter to convert stored energy into usable electricity for household appliances. In some cases, a backup generator is included to provide power during prolonged periods of low sunlight.
This setup is particularly valuable in remote or rural areas where grid access is limited or nonexistent, offering reliable electricity without dependence on utility companies. Off-grid systems ensure energy independence, protect users from grid outages and eliminate monthly electricity bills, though they require a higher initial investment due to the cost of batteries and specialized equipment. Additionally, they promote environmental sustainability by reducing reliance on fossil fuels and lowering carbon emissions.
To maximize efficiency, careful planning is necessary to ensure the system can meet energy demands year-round, especially during periods of low sunlight.
Advantages of an Off-Grid Solar System
- You can enjoy complete energy independence to make your house energy-efficient.
- It also works in remote areas.
- No or less electricity bills.
Disadvantages of an Off-Grid Solar System
- High initial costs.
- Periodically, you need to replace the old batteries at high prices.
- You also need to make changes in your lifestyle to minimise energy consumption.
- Extra produced energy could go to waste.
- Off-grid solar systems do not generate electricity at night and produce limited power during cloudy or rainy weather.
For those aiming for maximum sustainability, explore net-zero energy buildings (NZEB) as the ultimate goal.
Key Differences Between On-Grid and Off-Grid Solar Systems
| Aspect | On-Grid Solar System | Off-Grid Solar System |
| Connection to the Grid | Connected to the utility grid; relies on grid for backup. | Completely independent; not connected to the grid, fully self-sufficient. |
| Energy Storage | Usually does not require batteries (unless hybrid); draws from the grid when solar is insufficient. | Requires deep-cycle batteries to store excess energy for use at night or during cloudy days. |
| Cost Comparison | Lower upfront cost as batteries are not needed; installation is simpler and less expensive. | Higher upfront cost due to batteries, charge controllers, and backup generators; more complex setup. |
| Power Reliability | Power is available as long as the grid is up; during outages, only hybrid systems with batteries work. | Power is reliable as long as batteries are charged; not affected by grid outages. |
| Net Metering & Credits | Eligible for net metering; can earn credits or compensation for excess power sent to the grid. | Not eligible for net metering; no credits for excess power, as there’s no grid connection. |
| Maintenance & Lifespan | Minimal maintenance; no batteries to replace; generally longer lifespan. | Requires regular battery maintenance and replacement every 5-10 years; higher maintenance needs. |
What is Net Metering?
You can understand net metering as a utility billing mechanism that is available in most states. It offers credit to residential and business customers who generate extra electricity with their solar panel systems and send it back to the grid.
With net metering, you only pay for the electricity you actually use. That means you’re billed for the difference between the electricity your solar panels produce and the amount your home uses during the month.
Factors to Consider Before Choosing on-grid or off-grid solar systems
Before making a decision between choosing a grid-tied solar system or an off-grid solar system that suits your needs, evaluate the following:
Location: Check whether your area is connected to the grid electricity and gets enough sunlight, or if you are facing regular power outage problems. You may not need an off-grid solar system if you have a reliable power supply.
Budget: Consider your affordable budget. Whether it’s sufficient for battery storage, based on your requirement, make the proper decision. If you want to reduce costs and benefit from net metering, go for an on-grid solar system.
Energy needs: Consider your day-to-day energy requirements. If you need an uninterrupted power supply, you can choose a suitable option.
Environmental goals: Consider how much you want to reduce your dependence on the grid and lower your carbon footprint. Choose the system that aligns with your sustainability goals.
What is a Hybrid Solar System?
In a hybrid solar system, you can enjoy the advantages of both on-grid and off-grid solar systems. They use solar panels to produce electricity, store additional energy in batteries for later use, and stay connected to the local electricity grid. This system ensures an uninterrupted power supply during grid outages. You may qualify for net metering. Hybrid systems are more suitable for homeowners or businesses seeking energy independence, backup power, and the flexibility to draw from the grid when required.
Understanding the difference between on-grid and off-grid solar systems helps you to make better decision. While each system offers unique advantages, from the grid-tied system’s cost-effectiveness to the off-grid solution’s complete energy independence. The right choice always depends on your location, energy requirements, budget, and environmental goals. Before making a final decision, take suggestions from both solar installation experts and your home construction professionals to develop a comprehensive energy strategy customised to your specific property and requirements.
Mithali Konety