Homework Solution

TP 6-4

Given:

        March in Denver, CO

        flat plate collector

        tilt angle equal to latitude

        require 80 gal/day of water (8.3 lb/gal)

        DT = 70^o F

        efficiency = 40%

Find:

        required area of the collector

Science:

        Q = mcDT

        P_Q = IeA

Solve:

        From the Table in Appendix D of the course textbook,

        I = 2060 Btu/(ft² d)

        Q/(1 d) = [(80 gal/d)(8.3 lb/gal)] [1 Btu/(lb ^oF)] [70 ^oF] =  P_Q

         P_Q = 46,480 Btu/d

        A = P_Q /(Ie)

        A = (46,480 Btu/d)/[(2060 Btu/(ft² d))(0.4)]

        A = 56.4 ft²