Example 2: A school in a remote place has the following energy requirement: -Ten lamps each of 100 C.P that operate for 4 hours' daily - six computers, each 250 W that operate for 6 hours daily by a dual fuel engine driven generator - 2 hp water pump driven by a dual fuel engine driven generator for 2 hours' daily Calculate the size of the biogas plant and the number of cows required to feed the plant.

Example 2: A school in a remote place has the following energy requirement: -Ten lamps each of 100 C.P that operate for 4 hours' daily - six computers, each 250 W that operate for 6 hours daily by a dual fuel engine driven generator - 2 hp water pump driven by a dual fuel engine driven generator for 2 hours' daily Calculate the size of the biogas plant and the number of cows required to feed the plant.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.19P

See similar textbooks

Similar questions

A gas furnace has an output of 60,000 Btu/h. The return air temperature is 72F, and the temperature out of the furnace is 130F. Disregarding the heat the fan motor may add to the airstream, how much air is the furnace handling?
2.1 Taking the recent World Energy Council and United Nations resource-base figures forthe total amount of fossil energy in the ground worldwide as 356,000 quads, how longwill it take to exhaust our fossil resources, assuming that we can recover one-half of theresource base and that usage grows at 3% per year? The world currently consumes about400 quads of primary energy per year, of which 85% is from fossil sources. (Hint: youwill need to account for the compounding, exponential growth effect of the 3% per yearincrease in consumption.)
A refrigeration compressor with a C.O.P is 5.5 is driven by a motor with an output of 8 kW. Assuming 100% compressor efficiency, find the mass of ice per day at -8°C that this machine can theoretically produce from water at 19°C. 0.3672 tonnes/day 8.809 tonnes/day 84.74 tonnes/day 847.4 tonnes/day
A 4-kW heat pump is operated by a peasant. It should keep a duck hatchery at 32 degrees celsius, where heat is removed at a rate of 10 kW to the cooler ambient Tambient. What is the minimum COP for the pump that will be acceptable?
3) When a person enters his house, which is completely closed in summer, he sees that the temperature is 34°C. After turning on the air conditioner, the temperature of the house becomes 22 °C within 15 minutes. Since the efficiency coefficient of the air conditioning system is 3.2, a) the electrical power drawn by the system, b) heat dissipated to the environment, and c) Assuming that it works 8 hours a day and the electricity price is 0.6 TL per kWh, find its cost for 4 months. Assume that the entire mass inside the house is equivalent to 1000 kg of air. For air, take Cv = 0.73 kJ/kgK, Cp= 1.0051 kJ/kgK.
A computer lab filled with 20 computers and 15 students is cooled by an air conditioningunit on a day where it is 90 oF outside. The room temperature is 72 oF. Assume an averagestudent generate 90 W of heat and each computer generates 150 W of heat. If the COP ofthe air conditioner is 2.5, what power input is required, in kW? If the air conditioneroperated at its maximum coefficient of performance, what power input would be required?
An electric storage battery which can exchange heat only with a constant temperature atmosphere goes through a complete cycle of two processes. In process 1-2, 2.8 kWh of electrical work flow into the battery while 732 kJ of heat flow out to the atmosphere. During process 2-1, 2.4 kWh of work flow out of the battery. (a) Find the heat transfer in process 2-1. (b) If the process 1-2 has occurred as above, does the first law or the second law limit the maximum possible work of process 2-1? What is the maximum possible work? (c) If the maximum possible work were obtained in process 2-1, what will be the heat transfer in the process?
A central power plant, rated at 800 MW, generates steam at 585 K and discards heat to a river at 295 K. If the thermal efficiency of the plant is 70% of the maximum possible value, how much heat is discarded to the river at rated power?
If a house needs a minimum heat transfer rate of 75 kJ/h (i.e., 75 kJ of heat needs to be transferred into the house during one hour) to maintain a pleasant indoor temperature. If one wants to use a heat pump with a COP of 5.55 to fulfill this heat transfer rate, what is the corresponding electricity (in kWh) consumption to run such a heat pump for one hour?
For a power system operates with Wcycle = 810 BTU and Qout = 1769 BTU. What is the thermal efficiency?
A heat engine has a solar collector receiving 600 Btu/h per square foot, insidewhich a transfer medium is heated to 800 R. The collected energy powers aheat engine that rejects heat at 100 F. If the heat engine should deliver 8500Btu/h, what is the minimum size (area) of the solar collector?
The pressure of the air in a starting vessel is 40 bar and the temperature is 24°C. If a fire in the vicinity causes the temperature to rise to 65 °C. Neglect anyincrease in the volume of the vessel which is 5 liters. determine the: a. work nonflow and heat transferred