Optimization of wind power

Once the location of wind farm is selected based on the available wind data, next step is to optimize the wind power out put from the farm area using the available wind turbines from the manufactures. The spacing between the adjacent wind turbine is between 5 and 9 times of the rotor diameter in the prominent wind direction and 3 to 5 times perpendicular to wind direction. If needed CFD analysis can be performed to finalize the optimum layout. Higher rotor diameter increases the swept area of wind by increasing the wind turbine power. Higher hub height from the ground enables the rotor to use high velocity air available at higher elevation. Selecting a bigger rotor diameter and more hub height with latest transmission (mechanical to electrical energy) technology would maximize a wind farm power generation capacity, reduce the wind electricity generating cost and optimize the installation cost per MW capacity.

Barriers

Initial cost for wind turbines is greater than that of conventional fossil fuel generators and capacity expansion of existing hydro power plants with pumped storage hydro units. Noise is produced by the rotor blades. This is not normally an issue in the locations chosen for most wind farms.

Most of the wind power generation is during the south west monsoon season when rivers usually flood with water generating cheaper secondary hydro power. Scheduling the wind power which is unpredictable secondary power (even on daily basis), at fair price is a problem during monsoon season. Also adding additional pumped-storage hydroelectricity units instead of new wind power plants to produce predictable secondary power on daily basis during monsoon months and pumped storage operation for converting excess power in to peaking power during the rest of the year is more economical and commercial proposition.

When large wind power plants are located away from the load centers, laying dedicated transmission lines to evacuate the unreliable secondary wind power is additional cost liability. In India, solar power is complementary to wind power as it is generated mostly during the non monsoon period in day time.  Solar power plants can be located in the inter space between the towers of wind power plants or nearby area with common power evacuation facility. The wind power plant should guarantee minimum power generation/export in a year (say 15% capacity factor) to the purchaser.

In case the generation is below the guaranteed minimum power export, penalty should be applicable for the electricity which is short fall. This is to prevent over declaration of plant nameplate capacity to mobilize 100% debt financing by promoters without real equity contribution.

The wind power policy allows accelerated depreciation of the wind power plants cost out of the profits accrued from other businesses of a company to cut down the overall company’s tax liability. Businessmen are using short sightedly this window for reducing tax liability by installing cheaper wind mills of vintage technology based on supplier’s claims without liability. This method of wind projects financing and implementation is leading to inefficient harnessing of the available wind potential.

Wind power plants need very less land (less than one acre/MW for tower foundation, access road, substation, power evacuation lines, etc.) compared to other power generation technologies. It uses air space without effecting vegetation on the ground. Air space is a national resource similar to mines, spectrum, etc. Wind potential shall be auctioned to the highest bidder for its efficient use.  Already very good sites with attractive wind potential are harnessed without reaping optimum value.