Question

An often-overlooked consequence of power generation is "thermal pollution" from excess heat deposited in the envi- ronment. The heating can be considerable. Here are some typical numbers: A nuclear power plant generates 1.0 GW of electric power with an operating efficiency of 35%. The reactor has a single-pass cooling system; water from a nearby river is brought in, warmed, and returned to the river. When operating at full power, the plant takes in 90 m3 of water second, comparable to the flow of a small river. If the river water comes in at 10°C, at what temperature does it emerge?

Answer 1

Answer:

Explanation:

1 GW = 10⁹ W

35% of 10⁹ W

= 35 x 10⁷W

Q =  35 x 10⁷J

Mass of water

= volume x density

= 90 x 10³ kg

= 9 x 10⁴ kg

specific heat s = 4.142 x 10³ J / kg

Now

Q = ms Δ T

Δ T is rise in temp

Δ T = Q / ms

= 35 x 10⁷ / (9 x 10⁴ x4.142 x 10³)

= .94°C

So the emerging water will have temperature of

10.94 °C.