” وهو الذى أرسل الرياح بشراً بين يدى رحمته ، وأنزلنا من السماء ماءً طهوراً ” الفرقان - 48. And He it is Who sends the winds as heralds of glad tidings, going before His mercy, and We send down pure water from the sky,.
” وهو الذى أرسل الرياح بشراً بين يدى رحمته ، وأنزلنا من السماء ماءً طهوراً ” الفرقان - 48
And He it is Who sends the winds as heralds of glad tidings, going before His mercy, and We send down pure water from the sky,
Wind Resource Assessment ProgramPrepared byEng. Ashour Abdelsalam MoussaWind Energy Dep., New & Renewable Energy Authority (NREA)
COAL - 100 YRS.
OIL - 30 YEARS
GAS - 30 YRS
uranium - ???
Human Beings ???
World Wind Energy 2010
Worldwide capacity reached 196 630 Megawatt, out of which 37 642 Megawatt were added in 2010
All wind turbines installed by the end of 2010 worldwide can generate 430 Terawatt hours per annum, more than the total electricity demand of
the United Kingdom, the sixth largest economy
of the world, and equalling 2,5 % of the global
The wind sector in 2010 had a turnover of 40 billion Euro and employed 670’000 persons
China became number one in total installed capacity and the center of the international wind industry, and added 18 928 Megawatt within one year, accounting for more than 50 % of the world market for new wind turbines.
Germany keeps its number one position in Europe with 27 215 Megawatt, followed by Spain with 20 676 MW.
World Market Update 2009
March 2010 - Page 6
World Market Update 2009
March 2010 - Page 7
1.The Power in the wind is proportional to Cube of the wind speed (10% difference in wind speed makes about 33% change in wind power). This is the primary reason for wind resource assessment.
*Wind shears (large differences in the mean wind speed over the rotor) give large fluctuating loads and consequently fatigue on the wind turbine blades, because the blades move through areas of varying wind speed.
**Turbulence causes dynamic loads on wind turbines. The strength of the turbulence varies from place to place. Over land the turbulence is more intense than over the sea
Wind Resources assessments are the cornerstone of identifying and mitigating risks and for realizing the potential rewards from a project.
Without wind resource,
no wind project will even be viable.
Griggs – Putman Wind Index
This index is based on the permanent tree deformation caused by wind and is useful for estimating the average wind speed in an area.
Use vegetation to know wind direction and intensity
االساق عمودية والاغصان متحركة
الساق عمودية والاغصان ثابتة
ميل خفيف للاغصان
ميل كامل والساق عمودية على الارض
ميل جزئى للساق والاغصان
ميل شبه كامل للساق والاغصان
الساق والاغصان كالسجادة
Important to check direction when setting up instrument
Information in the resource assessment will include :-
The wind speed are binned, meaning that speed between 0 and 1 m/s are binned as 1 m/s, wind speeds between 1 and 2 m/s are binned as 2 m/s, and so on.
To assess a site’s wind power production potential, the wind speed frequency distribution must be multiplied by a representative wind turbine power curve.
Wind rose is a useful tool to know the wind blows.
It is a valuable tool for project layout and micro-siting
Wind Power Class Table
Low < 0.1
Medium 0.1 ~ 0.25
Large > 0.25
Turbulence intensity = standard deviation of wind speed/ mean wind speed
Once this assessment is completed, an accurate picture of wind resource at the site should be clear
Site Ranking Criteria
Note that the maximum possible score for each criterion is not the same. The differences reflect the relative importance of the criteria.
Micrositing is used to position one or more wind turbines within a given land area to maximize the overall energy output of the wind plant.
One km2 of the windy land can host 5 – 7 MW of potential installed capacity.
100 MW wind farm needs (15-20 km2)
Total power input
P/A= 0.5xxV3x 16/27
P/A= 0.5xxV3x 16/27x
The distances between the turbines have a strong effect on the energy output of the wind park.
This effect is described by the park efficiency the relation between :-
(the output of the park) / (the output of the same number of stand-alone turbines)
Wind turbines are typically arranged in rows perpendicular to prevailing winds.
If the wind is consistently from one direction then within-row spacing is less and row-to-row spacing is greater.
Within rows the spacing can vary from 1.5 to 5 times the rotor diameter.
Row-to-row distances typically vary from 10 to 20 times the rotor diameter.
For sites that have energetic winds from multiple directions, the row-to-row spacing and within row spacing are similar.
Typical array losses for a wind farm are 2~4 %.
The bottle-neck effect between two elevations
High elevation is good and typically means increased wind power
Variation of wind speed with height
Wind Speeds can be adjusted to another height using the power law equation :
V2 = the unknown speed at height Z2
v1 = the known wind speed at the measurement height z1
∝= the wind shear factor. it changes with different roughness, often assumed 0.14 over flat open terrain but can increase to 0.25 for area with forest or taller buildings.
This law takes into account the surface roughness of the surrounding terrain
Zo (Roughness Lengths)
Zo (Roughness Lengths) is the height above ground level where the wind speed is theoretically Zero
Please don’t hesitate to contact me for any question
e-mail : [email protected]