Homework Solution

TP 6-7

Given:

        power required  = 40,000 Btu/h       

        January in Minnesota

        flat plate collector, A = 700 ft²

        tilt angle equal to latitude

        efficiency = 50%

Find:

        percentage of the required power that can be provided by the flat plate collector

Science:

        P_Q = IeA

Solve:

        From the Table in Appendix D of the course textbook,

        I = 1410 Btu/(ft² d)

        P_Q  = [1410 Btu/(ft² d)] [1 d/ 24 h] [0.50] [700 ft²]

        P_Q = 20,562.5 Btu/h

        % provided = (20,562.5 Btu/h)/(40,000 Btu/h)(100 %) = 51.4%