热耗率公式

使用发电厂（工厂热耗率公式）或发电机产生一千瓦时 (kWh) 电力所需的总能量称为热耗率。它被定义为产生一单位电力所需的输入速率。热输入与电输出之比也可以表征为热速率；加热速率越小，效率越高。热力发电系统中的输入和输出能量通常在同一单位中测量。产生的热量总是与提供的化学能除以释放的电能成正比。

什么是热耗率？

The heat rate is the entire amount of energy required by an electric generator or power plant to create one kilowatt-hour (kWh) of electricity. 

它是产生单位功率所需的输入速率。热输入与电输出之比也称为热耗率。效率越高，热耗率越低。在热力发电系统中，输入和输出能量通常在同一单位中测量。产生的热量与提供的化学能除以释放的电能成正比。

热耗率公式

The formula of Heat Rate is,

R_h = Ws × c × ΔT

where,

• R_h = The rate of heat in btu/hr,
• W_s = In lb/hr steam flow,
• c = btu/lb degree F specific heat capacity
• ΔT = the difference in degrees Fahrenheit

示例问题

问题 1：如果蒸汽在 500 华氏度进入涡轮机并在 300 华氏度大气压下离开，计算热耗率。在典型运行期间，每小时有 600 磅蒸汽通过涡轮机。

回答：

Given : W_s = 600 Ib, c = 0.48, T_in = 500^oF, T_out = 300^oF

Find : R_h

Solution :

ΔT = T_in – T_out

∴ ΔT = 500 – 300

∴ ΔT = 200^oF

We have,

R_h = W_s × c × ΔT

∴ R_h = 600 × 0.48 × 200

∴ R_h = 57600 btu/hr

问题 2：如果蒸汽在大气压下以 700°F 进入涡轮机并在 500°F 退出，则计算热耗率。在正常运行中，每小时有 350 磅的蒸汽通过涡轮机。

回答：

Given : W_s = 350 Ib, c = 0.48, T_in = 700^oF, T_out = 500^oF

Find : R_h

Solution :

ΔT = T_in – T_out

∴ ΔT = 700 – 500

∴ ΔT = 200^oF

We have,

R_h = Ws × c × ΔT

∴ R_h = 350 × 0.48 × 200

∴ R_h = 33600 btu/hr

问题 3：发电厂的热耗率是什么意思？

回答：

In the context of thermal power plants, the term heat rate might be employed. These power plants, as we all know, convert thermal energy held in fuel (such as gas, coal, oil, and so on) into electricity (with the unit – kWh).

The heat rate is the quantity of heat required to produce 1 kWh (also known as Unit) of electricity. Its unit is kCal/kWh (but in certain cases it is kJ/kWh). The heat rates are expressed in British thermal units (Btu) per net kWh generated by the US Energy Information Administration (EIA) (net heat rate formula).

问题 4：如果蒸汽以 335 华氏度进入并在大气压下以 236 华氏度离开，计算热耗率。在正常运行中每小时通过 550 磅蒸汽。

回答：

Given : W_s = 550 Ib, c = 0.48, T_in = 335 degree F, T_out = 236 degree F

Find : R_h

Solution :

ΔT = T_in – T_out

∴ ΔT = 335 – 236

∴ ΔT = 99^oF

We have,

R_h = W_s × c × ΔT

∴ R_h = 550 × 0.48 × 99

∴ R_h = 26136 btu/hr

问题 5：如何区分涡轮热耗率和总涡轮热耗率？

回答：

Gross Heat Rate is defined as an expression of the total energy produced by the plant per one unit of mass of fuel in the calculation of any power plant’s output. This is before all parasitic loads, such as the effect of calculating Net Heat Rate or the power that really goes out the door per unit of mass of fuel, are factored in.

The gross heat rate takes into account the efficiency losses and power generated during the full power generating cycle, which includes the feed water circulation system, boiler, condensate recovery system, fuel delivery, and water treatment.