Questions: Question 3 For a building located in State College, PA - Tin = 70 F - Tout = 10 F - Peak heat loss - 12,000 Btu/hr - Electricity as the fuel for heating - 95% efficiency and 0.08 / kWh - HDD - 5,964 Calculate Aref Question 4 For the same question above, calculate annual heating energy use Btu Question 5 For the same question above, considering the fuel source - electricity, please calculate the energy cost () for annual heating

Solution Steps

We are given the following information for a building in State College, PA:

• Indoor temperature, \( T_{\text{in}} = 70^\circ \text{F} \)
• Outdoor temperature, \( T_{\text{out}} = 10^\circ \text{F} \)
• Peak heat loss = 12,000 Btu/hr
• Heating system efficiency = 95%
• Electricity cost = \$0.08/kWh
• Heating Degree Days (HDD) = 5,964

We need to calculate the reference area, \( \cup A_{\text{ref}} \).

The reference area, \( \cup A_{\text{ref}} \), is typically calculated using the formula for heat loss:

\[ Q = U \cdot A \cdot \Delta T \]

Where:

• \( Q \) is the heat loss (Btu/hr)
• \( U \) is the overall heat transfer coefficient (Btu/hr-ft²-°F)
• \( A \) is the area (ft²)
• \( \Delta T \) is the temperature difference (°F)

Given the peak heat loss is 12,000 Btu/hr and the temperature difference \( \Delta T = T_{\text{in}} - T_{\text{out}} = 70 - 10 = 60^\circ \text{F} \), we can rearrange the formula to solve for \( A \):

\[ A = \frac{Q}{U \cdot \Delta T} \]

However, without the value of \( U \), we cannot directly calculate \( A \). Therefore, we assume \( \cup A_{\text{ref}} \) is related to the peak heat loss and temperature difference, but further information or assumptions are needed to calculate it directly.

Final Answer