Home Solar Battery vs Generator: Which Is Best?

When the grid goes down, do you manage in the dark with no power, or do you wish you had a backup electricity option to keep essential appliances and systems running? For those seeking a reliable power source that runs even when the grid is out of order, two possibilities come into focus: solar batteries and fuel generators. But which one is the best choice?

The answer boils down to factors like cost, efficiency, environmental impact, and maintenance, and there are unique use cases that are better suited for each one. Let’s put these two options head to head and learn which is the right choice.

How does a fuel generator stack up against a solar battery? Both options differ widely in terms of the upfront and ongoing costs, efficiency and performance, environmental impact, and installation and maintenance.

Solar batteries have a higher initial cost but help you save money in the long term. If you don’t already have a home solar system installed, you may also need to purchase the equipment and installation, raising the total costs. However, government incentives are available to help offset these costs as well as save additional money while using the system by selling excess energy back to the grid.

Fuel generators have a lower initial cost but require ongoing fuel and maintenance, which adds up. They also may not last as long, so you’d need to purchase a new one while a solar battery is still going strong. This helps balance out the overall costs.

Modern solar batteries have impressive efficiency, determining how much energy is lost in the charge/discharge process. The more efficient the battery, the less power will be lost and the more cost-effective it will be. These batteries have a finite lifespan, and their performance will slowly degrade over time, so a new battery will eventually be needed. However, the manufacturer’s warranty may cover any issues within a certain number of years, assuring you of its performance during this period.

The type of fuel the generator uses impacts its efficiency—diesel generators tend to be more efficient than gasoline or natural gas generators. Still, factors like engine design and load management also come into play. A fuel generator can last between 10,000 and 30,000 hours of operation or anywhere from 5 to 20 years. This is pretty competitive with the lifespan of a backup battery; however, frequency of use makes a difference.

Solar batteries provide a clean and renewable energy source, running as long as sunlight is available without requiring additional fuel. They also produce no carbon emissions during operation. However, their manufacturing process does have environmental drawbacks, including raw material extraction, energy-intensive production, and disposal, which can contribute to pollution and resource depletion.

In contrast, fuel generators rely on fossil fuels like propane, gasoline, diesel, or natural gas. Their operation releases greenhouse gases and pollutants that contribute to environmental damage and climate change. Additionally, the fumes they emit can be harmful to both human health and air quality.

Solar batteries typically require a significant installation cost, which is more expensive than installing a standby gas generator. While the high installation costs can be off-putting to some homeowners, the savings realised once they’re operable help recover those costs within a few years. Batteries also require very little ongoing maintenance. They may need servicing or updates every year or two, but otherwise, they operate independently without requiring much manual input.

Fuel generators are cheaper to install but require extensive and expensive ongoing maintenance and fuel costs. To run the generator, you’ll need to continue purchasing additional fuel. If fuel is unavailable, it cannot run.

When deciding between a solar battery and a generator for backup power, it’s crucial to consider the scenario in which it will be used. Sometimes, a solar battery is the stronger choice, while a generator may stand out in others.

Do you already have a solar array on your roof or yard, or are you planning to install them? If solar power is already part of your home’s electricity system, or you intend to add it soon, then a battery makes the most sense because these two elements work together to provide sustainable, reliable electricity around the clock.

It’s safe to assume you’d like to keep lights and essential appliances running when a power outage strikes. If you want an automatic switch to backup solar power for these critical home systems without much effort, a battery would also be the best choice, as fuel generators require manual setup and refuelling.

Are you interested in renewable energy and hoping to eventually power your home with fully renewable electricity? A solar battery system like the EcoFlow Power Ocean (Three-Phase) is an excellent step toward complete energy independence.

Do you want to save money long-term on your electricity bills and take advantage of government incentives to lower the initial cost of your battery backup power solution? The UK has several incentives available for those who install a renewable energy system in their home, including solar batteries. These schemes can reduce the upfront cost. The Smart Export Guarantee also allows you to sell any excess power your system creates back to the grid to cut costs even more.

On the other hand, a fuel generator may be better if you answer ‘yes’ to any of these questions:

Are you looking for supplemental emergency power? A fuel generator is a simple and affordable solution if you only want to fill gaps in your energy supply as needed, such as during short outages.

Are you not interested in installing solar panels now or in the future? If solar power isn’t on your radar, solar battery storage won’t be helpful to you, as it requires a solar array to create and store power.

Does your home have an existing natural gas line? If you have a gas line to your home and would prefer to use that readily available power source, it would be easy to install a standby natural gas generator that can automatically kick on when grid power cuts out.

You can power your whole house with a solar generator and solar battery. Whether or not your solar generator system can support your entire home and all of its appliances depends on your system’s generation capacity and your battery’s storage capacity. 

Your solar panels will need to produce more energy than your home's total energy usage to ensure they will still generate enough power, even with the unavoidable loss of some of the energy during the charge/discharge process. 

The battery storage capacity also matters—solar panels can only produce power when the sun is out, so domestic battery storage becomes essential on overcast days or at night. If your battery storage is not large enough, you may deplete it entirely before it has time to create and store additional energy, leaving your home without power.

Solar generators only provide usable energy when the sun is out—without battery storage, you won’t be able to power your home or any appliances at night or on cloudy days. They are also much more expensive upfront than fuel generators. Finally, they may have slow recharge times and limited power capacity.

A solar inverter system with panels and a battery is generally a better option than a generator because it’s safe for the environment, operates without noise or fumes, helps you save over time, and provides reliable energy. Generators create carbon emissions, are noisy, and require ongoing fuel and maintenance costs.

While fuel generators have a more affordable initial price, they require more expensive and intensive maintenance and ongoing costs, making solar batteries a better financial decision overall. Solar batteries are also environmentally friendly, quiet and can run indefinitely without needing to refuel when connected to solar panels. You can install a comprehensive solar home battery system like the EcoFlow Power Ocean (Single-Phase) or find a battery storage option to retrofit your current solar array like the EcoFlow Power Ocean DC Fit. These solutions provide clean, quiet, and sustainable long-term electricity and increase your home’s energy independence.