Question about thermodynamics (heat loss)

AI Thread Summary
To determine the power required for the air conditioner in a poorly insulated house, the thermal conductivity of the walls and the temperature difference between inside and outside must be considered. The calculation provided estimates a heat loss of 16,380 W based on the wall thickness, surface area, and temperature difference. The discussion emphasizes the importance of calculating heat leakage through the walls as a first step. The reference to a Carnot refrigerator problem highlights the relevance of thermodynamic principles in this scenario. Accurate calculations are essential for understanding the energy requirements for maintaining a comfortable indoor temperature.
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Homework Statement


Suppose that you own a poorly insulated small house, with outside walls l = 0.25m thick, total outer wall plus roof
surface area 210m^2 (about 1992 ft^2) and your walls have a thermal conductivity of 1.3 W/m·K (limestone). Calculate
how much power your air conditioner will require to keep your house at 293K when the outside temperature is 308K.

Homework Equations



maybe dQ/dt = ak(dT/dx)

The Attempt at a Solution



i think

(1.3)(210)(15/.25) = 16380 W

but what do you think? have i made errors?
 
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This is a classic 'Carnot refridgerator' problem...

EDIT: Maybe this will help.

http://www.ohio.edu/people/piccard/phys202/carnot/carnot.html

Find an expression for the heat leakage first(through the walls).
 
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