Solar Insolation and Wind Energy Converters Have Pros and Cons - Nothing is Black or White
- Dec 23, 2019 12:33 pm GMT
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Solar Insolation is the amount of electromagnetic energy (solar radiation) incident on the surface of the earth. Basically that means how much sunlight is shining down on us. It is converted into DC power via photovoltaic (PV) cells or heat as concentrated solar power (CSP).
Wind energy is converted using wind turbines that drive asynchronous generators (actually motors) that produce variable frequency electrical energy that is converted to DC and then again to AC at the desired frequency, voltage and current with limited to no power factor control.
Also, the optimal wind speed span is very limited, too weak is not effective, too strong would topple the tower, blades are ‘feathered’ to slice the wind – present zero wind resistance for safety.
Common to the above is the fact that the available “free” energy is converted ‘as is’, there is - no extra “fuel” is available for volt-ampere reactive (VAR’s) as required for power factor correction.
The power factor is effected and ‘goes south’ (away from 1, down to 0.7-0.3), inductive or capacitive, by the type of the loads on the grid.
Those technologies are weather dependent therefore unreliable - require base-load, fossil-fueled electrical energy as back up – it is called ‘spinning reserve’. That is a costly liability – if those base-load back-up are not available, peaking units step in to support the grid at a higher cost.
Additional solar and wind generated electrical energy require new transmission lines that have 100% capacity, but operate only 25% of the time as renewable energy is available only about 25% of the yearly hours, about 2200 hrs/yr. This cost cannot be recovered.