If you live in a region where the public electricity grid is unstable or does not provide coverage, can operate a wind or solar photovoltaic (PV) system without relying on batteries?
The answer is yes.
For wind or PV systems, whether they are powering AC electrical equipment such as air conditioners, they need to be converted via a direct AC inverter.
The inverter is like a transport hub (power conversion). It can smoothly convert solar DC power into AC power, ensuring the stable and safe operation of your electrical equipment.
Next, we will take you into a new cognitive realm, where you can still use wind or solar power reliably even without batteries and mains electricity.
Do off-grid systems have to run on batteries?
In the field of solar and wind energy, systems are mainly divided into two types: off-grid and on-grid.
The core difference between the two is whether it can sell electricity to the local government or the power company, and only the on-grid system has this function.
On-grid systems, as the name suggests, must be connected to the city’s power grid to function properly.
Once the power grid fails or loses power, to ensure the safety of maintenance personnel, the on-grid inverter will immediately cut off all power. This causes electrical equipment to stop working.
So what about moving to off-grid systems?
In the PVMars system, off-grid systems are further subdivided into hybrid systems, on and off-grid systems, pure off-grid systems, and off-grid systems without batteries.
We take the PV system as an example to explain how an off-grid system operates.
Hybrid system: PVMars’ hybrid PV system can be connected to the city power grid, diesel generators, gel/lithium batteries, etc.
Its normal working mode is to give priority to solar power during the day and switch to battery power at night.
If the battery capacity is insufficient, the hybrid inverter automatically switches to the city grid.
Once the city power grid is out of power, the system will quickly switch to a diesel generator for power supply through the ATS (automatic dual power transfer switch).
This type of system is ideal for organizations such as radio stations that require 24-hour uninterrupted power supply.
On and off-grid systems: Similar to hybrid systems, PVMars’ on and off-grid systems can also connect to a variety of power sources, but their unique feature is that they can sell electricity to the government or power companies, while hybrid systems do not have this function.
For purely off-grid systems, PVMars are typically designed not to be connected to the city grid but instead rely on batteries or diesel generators for backup.
During the day, solar energy stores electricity for the battery through a charge controller. The off-grid inverter converts the battery’s DC power into AC power to meet the needs of the electrical loads.
It’s worth noting that the off-grid systems mentioned above typically require batteries to run.
However, there is a battery-free off-grid system that functions without batteries.
In addition, if the electrical loads (such as DC lights and fans) are all DC, the DC power from PV panels can be used directly through the solar panel and controller. They will provide power without battery intervention.
What is an off-grid battery-less wind or PV system?
In short, such systems do not require energy storage batteries.
If your electrical loads mainly operate during the day and the city power grid is not stable enough, to reduce battery costs, PVMars’ wide-voltage, non-energy storage off-grid inverter will be an ideal choice.
This system directly powers AC loads (such as air conditioners, motors, etc.) from solar panels without battery discharge.
It is suitable for users who use electricity during the day or want to reduce their electricity bills.
Features of this battery-free off-grid inverter include:
1- Provides sustainable energy for appliances no need batteries, city grid, or diesel generators when there is enough sunlight or wind, reducing initial battery costs.
2-Equipped with MPPT maximum power tracking, it prioritizes the use of solar or wind energy above 650V; when it is insufficient (below 400V), utility power will seamlessly replenish it, realizing 0-second switching.
3-Provides high-precision voltage stabilization and filtering to ensure stable sinusoidal waveform output even when the utility power is unstable, with voltage response time within 40ms.
4-With a unique anti-oscillation design, it can run stably even when there is no utility power, avoiding repeated switching and oscillation.
5-The inverter has been verified in harsh environments, with the characteristics of wind and sand resistance, moisture resistance, and salt resistance, and the service life is up to more than 15 years.
6-The power range of 3KW to 500KW can be customized and provides a variety of options such as rack, cabinet, channel steel, and waterproof/explosion-proof.
For more information on connecting solar panels to battery-less off-grid inverters, pls contact [email protected].
While there are many advantages to wide-voltage off-grid inverters without batteries, there are also limitations.
These battery-free off-grid PV systems cannot sell electricity and their power needs to be customized to the electrical load. The design approach can be found in the related design pathway.
The system is unable to supply power at night or in poor sunlighting conditions and is therefore not suitable for use in scenarios where a continuous 24-hour supply is required. Also, the lack of a storage battery buff may affect system stability.
However, these inverters can be combined with utility or diesel/gasoline generators to create a “hybrid energy system” or “microgrid” for seamless power supply and increased system stability.
In this configuration, the inverter provides power when there is sufficient sunshine and the utility or generator supplements it when there is insufficient sunlight.
PVMars’ intelligent control system enables seamless switching between power sources to ensure a stable supply.
When choosing this type of inverter, comprehensive consideration should be given to the actual needs and usage scenarios to meet the power and economic requirements.
In situations where utility power is unstable and no diesel generator is available, consideration should be given to adding batteries or generators for nighttime backup.
If nighttime power is required, please continue to learn which is more suitable: a diesel generator or a battery.
As a backup power source, between diesel generators and batteries, who is better?
First, we need to understand why wind and PV systems need backup power. The core reason is that the power generated by wind and solar is not stable.
Wind and sunlight are not constant, e.g. when clouds block the sun, solar panels receive less solar radiation, which affects the voltage and power output; wind turbines also lose power when the wind is weakened.
Traditional diesel generators are noisy and require frequent maintenance, with oil maintenance required every three months on average.
While newer generators have become progressively quieter and more technologically upgraded, they still rely on diesel, a non-renewable resource.
That’s why even Google has made the switch to replacing diesel generators with batteries for energy storage. See the article “Replacing Diesel Generators with Lithium-Ion Battery Storage Systems is a Good Idea” for an example.
In addition, PVMars’ customers in the Democratic Republic of Congo have made the same choice, replacing their diesel generators with solar energy storage systems.
PVMars also offers a wide range of battery options for your wind or PV system, such as colloidal batteries, lithium iron phosphate batteries, or liquid current batteries.
Although these batteries account for about 30% of the cost of a complete PV system, they offer many advantages such as high safety, 0 noise, maintenance-free, and a long service life (12-15 years).
Compared to diesel generators, these batteries are undoubtedly a better choice for energy storage systems.
