A building in a processing facility has been retrofitted for a new process. There is a need for hot water in this new process. The original design of the building did not include a hot water line. Adjacent to this building is another building that has a hot water line that can be used. The proposal is to run a 1-nom sch 40 commercial steel pipe (k = 54 W/m-K) above-ground from one building to the other. The total length of pipe exposed to the outdoor air is 5 m. The hot water flows in the pipe at a rate of 1 kg/s and has a yearly average temperature of 52°C. The hot water is made using electricity which has a cost of $0.08/kWh. The average monthly weather data for the location is given in Table P5.11. Estimate the yearly cost of electrical energy lost due to the convective heat transfer from the exposed outdoor pipe.

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TABLE P5.11 Average Monthly Weather Data Average Outdoor Temperature (C) Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec -0.3 2.5 6.9 10.3 15.3 19.7 24.2 23.4 18.3 11.7 4.4 -0.6 Average Wind Speed (m/s) 15.3 16.0 4.1 5.2 14.2 8.1 8.4 5.7 3.6 10.7 11.8 9.1