THE ANSWER TO THE POWER AVAILABILITY QUESTION
By Mercy Masai
What is a Hybrid Power System?
This is an alternative approach to producing clean, non-polluting energy from two of the most abundant renewable energy sources, and are systems that combine solar power from a photovoltaic system with another power generating energy source that is wind. Solar and wind hybrid power systems are designed using solar panels and small wind turbine generators for generating electricity.
Why select a Hybrid system?
The small wind feature combined with solar panels allows for electricity generation on sunny days with little wind or windy days with or without sun, making ideal for many parts of the country during almost any conditions. Having a combination system allows one to take the most advantage of the prevailing weather conditions to maximize energy production.
How does the Hybrid system work?
Using Solar Panels – That are photovoltaic which, generate electrical energy using sun light radiations..
Using Wind Turbines? That have large blades which are joined to rotor of a generator leading to the production of electrical energy as moves by flow of wind.
- Wind turbine first converts the kinetic energy to mechanical energy and then converts it to the electricity. The wind turbine in the system consists of tower, alternator, speed converters and propeller. The kinetic energy of the wind is converted to the mechanical energy in the rotor. The rotor shaft speed, is accelerated in the reduction gear and then transmitted to alternator. The electricity that comes from the alternator can be directly transmitted to DC receivers as well as it can be stored in the batteries.
- The solar panels in the system convert the day light directly in to electricity.
- The batteries in the system provide to store the electricity that is generated from the wind or the solar power. Any required capacity can be obtained by serial or parallel connections of the batteries.
What are the applications of solar wind hybrid?
The solar wind hybrid systems are used where the load is relatively small and places where there is power shortages. This includes:
- Rural offices (rural health centers , agricultural center offices)
- Schools especially in rural and urban fringe areas.
- Military (charging of communication units)
- Railways (track signaling).
- Street lights
Advantages of Solar Wind Power System
- When one source isn’t available the system will still be able to provide energy from the alternate energy source. The clean, emission-free power acts as a reliable backup or supplemental power source.
- When both sun and wind is present, the batteries will charge even faster.
- Solar panel have a higher initial cost than wind turbines. With this hybrid system, you can spend more on wind power to offset the number of required solar panel and still achieve the same output.
- Solar panels require very little maintenance while wind power need only periodic service
Disadvantages of Solar wind system
- The solar panels and wind turbines need to be adequately sized to supply enough power to the batteries. If insufficient energy is produced, the batteries will not be fully charged in a convenient time frame. If too much power is produced, the extra energy will simply be wasted.
- Solar panels require adequate room with full exposure to the sun; wind turbines need unobstructed access to the wind.
- Wind power will generate some noise as the blades rotate in a strong breeze.
Systems need to be designed for the maximum amount of electricity that will be generated from both sources..
Other system considerations include:
- The solar panels should be in an open area free of obstructions and shadows.
- The wind turbine should be attached to a secure mounting pole as high as possible with full exposure to air currents.
- Ensure that the wind turbine does not shadow the solar panels.
- When doing maintenance, disconnect the entire system since the other power source may still be able to deliver electricity.
- The wires should be thick enough to handle the maximum current load from both systems
The concept behind combining the two types of systems together is to try and achieve constant power production, to increase availability. The scalability of this system however, goes beyond just powering a house or any large system, but to provide a power solution for remote areas that are not fitted with an electric distribution system. This would resolve power deficiency and provide useful solutions in many locations around the globe.
- Agrawal, Ashish, Richard Wies, and Ronald Johnson. Hybrid Electric Power Systems Modeling, Optimization and Control. Saarbrücken: VDM Verlag Dr. Müller, 2007. Print.
- A. Razak, K. Sopian, and Y. Ali, “Optimization of renewable energy hybrid system by minimizing excess capacity,” International Journal of Energy, vol. 1, no. 3, 2007. View at Google Scholar