Wind-Solar Hybrid Inverters: Illuminating a New Future for Farms

As global energy demand continues to grow and environmental awareness rises, traditional energy supply methods are increasingly revealing their limitations, especially in fields such as farms. Farms, as relatively independent production areas, have high demands for stable and reliable electricity supply. On one hand, farm lighting, monitoring systems, and various farming equipment require continuous power support; on the other hand, environmental protection requirements are pushing farms to seek cleaner, more sustainable energy solutions.

In this context, the wind-solar hybrid inverter has emerged as a new choice for farm power supply. The wind-solar hybrid inverter combines the advantages of both wind and solar energy, two renewable resources, and can fully utilize the farm’s abundant natural resources for power generation. In many regions, farms often have vast land and good natural ventilation conditions, providing an ideal environment for wind power generation. At the same time, ample sunlight makes solar power generation feasible.

The application of wind-solar hybrid inverter not only reduces the farm’s energy costs but also decreases dependence on traditional fossil fuels, offering strong support for sustainable development. Compared to traditional single-energy power supply methods, the wind-solar hybrid inverter offers higher stability and reliability. When wind power is insufficient, solar energy can supplement the electricity; conversely, during cloudy days or at night, wind power can continue to supply energy to the farm. This complementarity ensures more stable power supply and reduces the risk of production disruptions due to energy shortages.

Additionally, the installation and maintenance of wind-solar hybrid inverters are relatively simple, requiring minimal human and material resources. They can be customized to meet the specific power demands of farms of various sizes. Environmentally, wind-solar hybrid inverters produce no pollutants, have no negative impact on the farm’s ecological environment, and meet the green development requirements of modern society.

2. Suitable Farm Conditions for Installation

(1) Rich Natural Resources

The Fengning Bashang region in Chengde, Hebei, is one of the nine major clean energy bases designated by China’s “14th Five-Year Plan.” It has abundant natural resources, making it an ideal location for installing wind-solar hybrid inverters. Here, white wind turbines stand tall on the vast grasslands, with an average altitude of 1,500 meters. As a natural pasture, it boasts rich wind and solar resources. Cattle graze leisurely, while densely arranged solar panels follow the terrain’s ups and downs, with inverters running steadily beneath them. The region’s 700,000 kW solar project, equipped with 3,112 Kostal 225 kW string inverters, is expected to generate an average of 1.8 billion kWh per year, reducing CO2 emissions by about 1.4 million tons, offering both economic and ecological benefits.

Northwest China’s pastures are similarly ideal for installing wind-solar hybrid inverters. These areas have vast land and good natural ventilation, providing an excellent environment for wind power generation. Additionally, abundant sunlight makes solar energy generation viable. For instance, a farm in Lhasa, with an average temperature of 15°C and an altitude of 3,000 meters, receives a solar radiation total of 2,150 kcal/cm, with an average annual sunshine duration of 3,000 hours. The region is rich in wind energy, with an annual effective wind energy density exceeding 200 W at 2 meters and an average usable wind speed of 4.4 m/s, ensuring long-term continuous power supply through the combination of wind and solar energy.

(2) Geographic Limitations

Farms in areas like Lhasa face geographical limitations that make power supply inconvenient. In such cases, off-grid power systems are often considered, making them suitable for wind-solar hybrid inverter. To ensure continuous power supply in scenarios where both wind and solar are unavailable, batteries must be configured in the system to maintain normal power supply for up to 5 days. In these geographically constrained farms, the wind-solar hybrid inverter can fully leverage local wind and solar resources to provide stable and reliable power for lighting, monitoring systems, and other equipment. Even in harsh geographical conditions, the installation and maintenance of these inverters are relatively simple, requiring minimal human and material resources. The system can be customized to meet the specific power needs of farms of various sizes.

3. Advantages of Wind-Solar Hybrid Inverter

(1) Stable and Reliable Power Supply

Wind-solar hybrid inverter have shown exceptional adaptability in farms, ensuring stable operation even in high-altitude or large temperature difference environments. For example, in the northwest Chinese pastures, which have high altitudes and variable climates, the wind-solar hybrid inverter can still provide a continuous and stable power supply for lighting and monitoring systems. In high-altitude areas, where the air is thin and traditional power equipment may be affected, the wind-solar hybrid inverter can work normally due to its advanced technology and reliable performance. Similarly, in areas with large temperature differences, the inverter can withstand challenges without malfunctioning due to temperature changes. Whether in hot summers or cold winters, the wind-solar hybrid inverter ensures the stable operation of farm systems, providing strong support for production and management.

(2) Green, Environmentally Friendly, and Energy-Saving

By fully utilizing wind and solar energy, both renewable and pollution-free sources, the wind-solar hybrid inverter aligns with modern environmental standards. On farms, this green energy solution not only reduces dependence on traditional fossil fuels but also saves a significant amount of electricity. According to statistics, a medium-sized farm equipped with a wind-solar hybrid inverter can save thousands of kilowatt-hours annually, greatly reducing energy costs. Furthermore, as no pollutants are produced, these inverters have no negative impact on the farm’s ecological environment, helping preserve ecological balance and promoting sustainable development.

(3) Cost Reduction

In farm power supply systems, proper battery configuration and selecting suitable inverter solutions are key to reducing costs. For wind-solar hybrid systems, battery capacity and quantity play a crucial role. By reasonably configuring the batteries, the system can provide continuous power even when wind and solar energy are insufficient. Additionally, choosing efficient and reliable inverters can improve energy conversion efficiency, reduce energy loss, and lower overall power supply costs. For example, inverters with intelligent management functions can automatically adjust power generation according to the farm’s actual electricity needs, optimizing energy distribution. Moreover, the installation and maintenance costs of wind-solar hybrid inverters are relatively low, saving the farm additional expenses.

4. Inverter Role in Farms

(1) Intelligent Charge and Discharge Control

The intelligent charging control design of the wind-solar hybrid power generation system is key to ensuring continuous, stable operation. Using a microcontroller at the core, the system collects current, voltage, and temperature data, inputting them to the microcontroller’s A/D interface to control charging and discharging conditions. It determines system operation status based on set values and controls charging and discharging processes. When the battery is fully charged and the power generation exceeds the load’s consumption, the system switches on a load dump to dissipate excess power, preventing overcharging of the battery and ensuring proper inverter operation. This intelligent design allows the system to adjust charging and discharging strategies based on the farm’s actual power usage, ensuring the battery remains in optimal working condition.

(2) Working Principle

The working principle of the wind-solar hybrid inverter involves charging control from both wind turbines and solar arrays, as well as inverter circuit functionality. The wind turbine’s AC output is rectified into a pulsating DC voltage to charge the batteries. When the battery voltage reaches a specified level, the inverter switches off charging from the turbine to prevent overcharging. Similarly, when the solar array’s voltage reaches the overcharge threshold, it uses a field-effect transistor to disconnect charging. The entire control circuit consists of a microprocessor (PIC16C711) and associated components, which manage turbine charging, solar charging, inverter protection, and other functions.

5. Application Case Studies and Future Prospects

(1) Successful Case Example

In Ningxia, the HEMAI module-level power electronics technology helps a dairy farm achieve “solar power generation and livestock farming.” The second dairy farm of Ningxia Ninkang Dairy is located in Pingluo County, Shizuishan City, specializing in dairy cattle breeding, forage production, and fresh milk production. With abundant wind and solar resources, the area receives approximately 2,988.9 hours of sunlight annually. In this project, HEMAI used a one-to-four micro inverter system paired with customized BIPV roofing, ensuring the photovoltaic station operates safely while maximizing power output and reducing electricity costs. Due to the presence of ammonia and flammable feed, safety is a top priority. The micro-inverter system stabilizes the DC side at around 40V, eliminating fire and electric shock risks, making it perfect for farms with hazardous conditions. Since its implementation, the system has saved 4,124.15 tons of standard coal annually, reducing CO2 emissions by 13,000 tons, equivalent to planting 720,000 trees, successfully achieving an energy transformation.

(2) Future Development Prospects

Wind-solar hybrid inverters have vast potential for farm applications. As global attention to renewable energy grows and the livestock industry increasingly seeks sustainable development solutions, these inverters will play a pivotal role in driving energy transitions within the industry. By leveraging abundant natural resources and reducing energy costs, wind-solar hybrid inverters will help enhance productivity and sustainability. Additionally, their eco-friendly nature aligns with societal demands for green development, reducing the environmental impact of the livestock industry. With continued technological advancements, performance will improve, costs will drop, and installation and maintenance will become even more convenient. This will lead to broader adoption of wind-solar hybrid inverters, promoting a more sustainable, efficient, and green livestock sector.