Question

In the sun, 1000g of hydrogen fuses to 993g of helium while the other 7g of matter is converted into energy using Einstein's famous equation E=mc2, where c is the speed of light (3.0*108m/s).

~ What is the ratio of the energy released by the fusion of 1.0 kg of hydrogen to that released by fission of 1.0 kg of Uranium-235?

~Given the obvious advantage in energy production, briefly describe some of the difficulties in designing and operating a fusion power plant to explain why there are no commercial fusion power plants in operation today.

Answer 1

a)

b)   there are no commercial fusion power plants in operation today because

For fusion to occur on Earth, you need a temperature of at least 100 million degrees Celsius—six times hotter than the core of the sun. The sun is a natural fusion reactor which makes up for its measly 15 million degrees with the intense pressure created by its core's gravity. Currently, here on Earth the amount of energy you'd need to put in to produce that kind of heat or pressure is much, much higher than what you get out in usable energy.

That's where the term cold fusion, the hope that fusion reactions can occur at relatively low temperatures, comes in. Once a promising theoretical goal, the field was largely written off as pseudoscience the late 1980s, when electrochemists Stanley Pons and Martin Fleischmann reported that their room-temperature electrolysis experiment had produced so much excess heat—as well as nuclear by-products like tritium—that only a nuclear reaction could be blamed. The attention led to a massive wave of cold-fusion experimenting, but no one was able to replicate their heat anomaly.