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Homework Help: Wind Power Generation Comparison

  1. Feb 5, 2012 #1
    1. The problem statement, all variables and given/known data

    Two sites are being considered for wind power generation. In the first site, the wind blows steadily at 7 m/s for 3000 hours per year, whereas the second site the wind blows at 10m/s for 2000 hours per year. Assuming wind velocity is negligible at other times for simplicity, determine which is a better site for wind power generation. Hint: note that the mass flow rate of air is proportional to wind velocity.

    2. Relevant equations

    E = me

    3. The attempt at a solution

    Ok so I found e1 and e2 with the first equation.

    Which gives me 24.5 and 50 J/Kg (respectively)

    But i'm stuck now. How can I find m? It says that that the mass flow rate of air is proportional to wind velocity but how can I tie in time? Any hints would help.

    I can tell that the second site would be more efficient, but I can't explain why.
    Last edited: Feb 5, 2012
  2. jcsd
  3. Feb 7, 2012 #2


    User Avatar

    Staff: Mentor

    They are probably wanting the site with the highest annual mass flow, where
    mass flow = mass flow rate x time
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