29-11-2012, 06:21 PM
Wind Hybrid Systems
Wind hybrid systems ppt.pdf (Size: 639.88 KB / Downloads: 44)
Overview: Wind/Solar Hybrid Systems
Erratic energy sources like wind and solar are not dispatchable, that is, available on command of utility dispatchers
Sometimes or often, the wind blows when it is cloudy, or the sun shines when the wind is calm
A system that combines various energy sources is called a “hybrid” system
Diesel generators are often used for “reliable” power, and wind or solar are used to decrease the fuel costs
Studies of a site can indicate the optimal combination of wind, solar, and diesel (or gasoline) to provide power at the lowest overall annual cost
Energy Source Mixture Availability
Assessment of wind vs. solar for a specific site uses a small representative turbine or anemometer and a PV module
The energy ratio plotted throughout a year indicates the relative energies available, which can then be compared with system cost ($/kWh)
The actual energies available can then be compared with longer-term climate data to estimate annual variations
Life-cycle costs of the two systems must be included to get a comprehensive determination of an optimal system design
One of the systems might be omitted if the energy contribution is less than ~5% of the total
Why bother if $/kWh is too high?
Wind/Diesel
Wind/diesel systems work well where sunlight is limited, as above the Arctic Circle or below the Antarctic Circle
Wind turbines have worked well at the South Pole Station, but diesel generators are also hard at work there
Gasoline engines also can be used, but may lack the life of a heavy diesel engine
Propane Engine Generator
Liquefied petroleum gas (LPG) in the United States is primarily propane, but also contains propylene, butane, and butylene
Gasoline-carbureted generators may be converted to propane; often done in pickup trucks in Western US
The Onan (Cummins) generator shown below produces 5.5 kW and costs ~$2970 (~$540/kW)
One gallon/hour of liquid propane will produce ~10kW