Respuesta :
Answer:
T = 385.2 years ... constant rate of consumption
T = 44.707 years ... 5.15% increase per year in average consumption
Explanation:
Solution:
- Obtain the value of consumption rate fromm Example 8-3.
Consumption Rate = 128.5 EJ / year
- The efficiency of coal fired power plant was raised to 40%:
A = efficiency * consumption rate
A = 0.40*128.5
A = 51.4 EJ /year
- For the case demand D = 19,800 EJ remains constant and international consumption at C = 120.8 EJ, the time to exhaustion would be:
Time = D / A
= 19,800 EJ / 51.4 EJ /year
= 385.2 years
- For average consumption of coal based increased at R = 5.15% per year, the reserves will last according to growth expression as follows:
[tex]D = C*\frac{(1 + \frac{R}{100})^t - 1 }{\frac{R}{100}}[/tex]
- Solve for time t:
R*[D/100*C] + 1 = ( 1 + 0.01*R)^t
Ln | R*[D/100*C] + 1 | = t*Ln | 1 + 0.01*R |
t = Ln | R*[D/100*C] + 1 | / Ln | 1 + 0.01*R |
t = Ln | 0.0515*[19,800/120.8] + 1 | / Ln | 1 + 0.0515 |
t = 44.707 years
