An electricity-generating station needs to deliver energy at a rate of 20 MW to

Question

An electricity-generating station needs to deliver energy at a rate of 20 MW to a city 1.0 km away. A common voltage for commercial power generators is 22 kV, but a step-up transformer is used to boost the voltage to 230 kV before transmission SOLVE IT (A) If the resistance of the wires is 2.2 and the energy costs are about 10 cents/kWh, estimate what it costs the utility company for the energy converted to internal energy in the wires during one day. Conceptualize The resistance of the wires is in series with the resistance representing the load (homes and businesses). Therefore, there is a voltage drop in the wires, which means that some of the transmitted energy is converted to internal energy in the wires and never reaches the load Categorize This problem involves finding the power delivered to a resistive load in an AC circuit. Let's ignore any capacitive or inductive characteristics of the load and set the power factor equal to 1 Analyze CalculateIrms in the wires using the equation for average power delivered to an RLC circuit: 2.0 x 107 w 2.30×105 V avg =87 A AVrms Determine the rate at which energy is delivered to the resistance in the wires from the fact that average power delivered by the source is converted to internal energy in the resistor: Pava = 12rmsR = (87 A)2(2.2 ) = 17 kW avg ms Calculate the energy TeT delivered to the TET = P/ (17 kW)(24 h) = 408 kWh

Explanation / Answer

Irms = Pave/V = (2.0*10^7)/(2*230?*10^3) = 43.5

Pave = Irms2*R = 43.5^2*2.2 = 4163 W

TET = 4163W*24h = 99.9 kWh

Cost = 99.9*0.10 = $10.0

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.