Explore India's Wind Energy Potential

re:wind is used to explore wind patterns in India and understand the potential of different locations to generate wind power.

Features

The wind speed and wind power for each position can be viewed along with the seasonal variations by selecting specific year and stepping through the different months. The user can also take a focused look at different states. The values are visible by clicking on any grid location. In addition, the top 10 wind farms and the states with the highest wind potential (at 150 m height) are highlighted.

Data and Methods

Raw Data

This tool is based on the climate data from NCMRWF. The main data used here is the mean wind speed at a height of 10 metres above the surface over the period 00h-24h local time at a horizontal resolution of 0.1° x 0.1° (latitude-longitude) grid. This data is overlaid on the state boundaries of India provided by the Survey of India (SOI).

Analysis

The wind speed data for each day is then aggregated to calculate the mean for each month. Thereafter, the mean of monthly means is used to calculate the annual mean value for each grid. This has been done for the years 2022, 2023 and 2024. The minimum and maximum values were used to generate a color graded output with purple denoting the highest and blue the lowest wind speeds respectively (see legend).

Extrapolation of wind speed at target height

Based on the user-entered blade length, the hub height or target height is calculated using the following formula:

$Z = 2.5 \times Blade\_length$

An alpha value of 0.143 is used to extrapolate the wind speed at 10 meter to the target height based on the formula:

$V(Z) = V_{ref} \times (\frac{z}{z_{ref}})^{\alpha}$

where,

• V(z) is the predicted wind speed at target height
• Z_ref is the reference height (10m)
• V_ref is the wind speed at reference height
• Z is the target height
• α(alpha) is the power law exponent

Calculation of wind power

The extrapolated wind speed data at target height (based on chosen blade length) is used to dynamically calculate the wind power.

The empirical formula to compute the power derived from a wind turbine (in Watts) is:

$P = \frac{1}{2} \times C_p \times \rho \times \pi \times R \times V^3$

where,

• Cp is the coefficient of performance (efficiency factor, in percent)
• ρ is air density (in kg/m3), (in most cases considered as 1.23 kg/m)
• R is the blade length (in metres)
• V is the wind speed (in meters per second)

References

1. National Center for Medium Range Weather Forcation - Ministry of Earth Sciences, Government of India
2. Wind Overview - Ministry of New and Renewable Energy
3. Indian state boundaries from UGIX (SOI)
4. Largest wind farms in india