Basic principles and applications of wind and solar hybrid system design

Basic principles and applications of wind and solar hybrid system design

To put it simply, the wind-solar hybrid system combines solar and wind power generation, coupled with energy storage devices, to form a micro-smart grid that can independently supply power to homes or small places. The core concept of its design is to utilize the natural complementarity of two energy sources to achieve a more stable and reliable power supply than a single system.

1. Basic Principle: Space-time complementarity and system balance

Resource complementarity: This is the fundamental basis of system design. Solar energy has significant diurnal and sunny changes, with strength during the day and absence at night; wind resources often have different patterns in seasons, day and night, for example, the wind may increase at night or in cloudy and rainy weather. The two naturally complement each other in terms of time and weather, thus smoothing the power generation curve and reducing the "power generation window period."

System balance design: The key to design is to pursue the dynamic balance of "power generation", "power storage" and "power consumption". That is, according to the user's power demand, the proportion of solar and wind power generation, the capacity of the battery, and the control strategy are reasonably configured to ensure that power supply and demand are self-consistent most of the time and avoid waste of power generation or insufficient power supply.

2. Core design steps and key points

Needs analysis and resource assessment:

Clarify electricity demand: Calculate in detail the household's daily and quarterly electricity consumption (kWh), and distinguish between key loads (such as refrigerators, lighting) and adjustable loads.

Assess local resources: Obtain local average annual sunshine hours and wind speed data. Through on-site observation, determine whether the installation location has sufficient, unobstructed sunlight and stable and considerable wind. This is the basis for determining system configuration and economic benefits.

Power generation unit configuration:

Photovoltaic modules: Calculate the total power of solar panels required based on electricity demand and sunlight conditions. Installation orientation (usually due south), tilt angle and avoidance of occlusion are key.

Wind turbine: Choose a model with appropriate power and starting wind speed based on wind speed data. It needs to be installed in an open, high-rise location with low turbulence. In areas where the average wind speed is less than 4 meters/second, the contribution of wind energy is often limited and needs to be carefully evaluated.

Energy storage and control system design:

Battery Capacity: This is the "stabilizer" of the system. The capacity depends on how much energy needs to be stored to cope with continuous cloudy days with no wind or light. If the capacity is too large, the cost will increase; if the capacity is too small, the protection will be insufficient.

Intelligent controller: the “brain” of the system. It must be able to efficiently manage both photovoltaic and wind power inputs, intelligently distribute power (prioritizing load supply and recharging), manage battery charge and discharge (prevent overcharge and overdischarge), and achieve seamless switching.

System integration and installation:

Choose a matching inverter (convert battery DC power into household AC power) and design a safe power distribution and lightning protection system.

Make sure the installation is firm, especially the tower pole of the wind turbine, which needs to be able to withstand strong winds.

3. Main application scenarios

Remote areas not covered by the power grid: such as pastoral areas, islands, and mountainous areas, providing main power for households, outposts, weather stations, etc.

Places with high power supply reliability requirements: such as communication base stations, border defense sites, and important monitoring facilities, can be used as main or backup power sources to improve the level of security.

Households pursuing energy conservation and energy independence: In cities or suburbs, it can be used as a supplementary power source to reduce electricity bills and provide emergency power in the event of a grid outage.

Summary: Adjust measures to local conditions and optimize configuration

There is no fixed template for the design of the wind-solar hybrid system, and its essence lies in adapting measures to local conditions. In areas with good sunshine and weak wind, photovoltaics should be the main method and wind turbines should be supplemented; in areas with abundant wind energy and average light, the opposite should be done. Successful system design must be based on solid local resource data and clear power demand, achieve the complementary effect of "1+1>2" through optimized configuration, and ultimately provide users with an economical, reliable, and green independent energy solution.