Albadi & EI-Saadany - Overview of wind power

Question 1

Why has wind-power recently faced such a strong growth? (Three reasons)

Answer 1

1. Climate change awareness
2. Limits of fossil energy sources
3. Technological improvements of wind-turbines, causing lower costs

Question 2

How well predictable are temporal variations of wind energy?

Answer 2

• Decades: Very stable
• Annually: Harder to predict
• Seasonally: Well predictable
• Daily: Well predictable (a few days ahead)
• Hourly variations: Well predictable (on the day)
• Minutes: Harder to predict

Question 3

What causes spatial variations of wind energy (globally and regionally)?

Answer 3

Globally:
- Altitude
- Solar insulation
Regionally:
- Sizes of land and sea
- Presence of mountains or plain areas

Question 4

What effects has wind energy on the operation of conventional generation?

Answer 4

• Regulation (minutes/seconds), to maintain demand-generation balance: modest due to smoothing effect
• Load following (ten minutes/hours): expands with large-scale wind integration
• Scheduling/unit commitment (availability of hours/days ahead): uncertainty creates higher costs, but still modest

Question 5

What can reduce variations?

Answer 5

• At certain point in time: Many turbines in a wind park
• Medium-time (within a day): Wind parks with distance from another

Question 6

What national attributes influence the integration costs of wind energy?

Answer 6

• Cheaper in hydro dominated countries, than in thermal stations dominated countries (like Germany)
• Integration costs are lower if the wind parks are more spread out (costs higher in Germany, where coast lands dominate wind energy, than in Nordics)

Question 7

Problems with wind power

Answer 7

• Fluctuation of wind power causes less efficient operation of wind power plants
• An increase in reserve power is needed
• Wind turbine needs to be curtailed to ensure stable operation
• Scheduling of reserves to secure the energy