{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Bio36_15_Nuclear - 1 2 1 2 3 4 5 1 2 6 1 2 7 1 Overview Ch...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Overview Ch. 15: Nuclear Power – History of Nuclear Power – How Nuclear Power Works – Nuclear Wastes – More Advanced Reactors – Future of Nuclear Power History of Nuclear Power The Nuclear Age – Development of nuclear power plants after WWII Curtailed after 1975 – Orders cancelled – 28 units have been shut down in U.S. Current situation – 104 in operation in U.S. – 19% of U.S. electricity Global picture – 439 in operation – 14% of world’s electricity Nuclear Share of Electrical Power How Nuclear Power Works Control nuclear reactions – Energy released gradually as heat – Heat boils water to drive turbogenerators • Mass barb2right energy – Fission: large atom split into 2 smaller atoms – Fusion: 2 small atoms combine into a larger atom Nuclear Fuel Fission of uranium-235 – Isotope 235 U: mass # = 235 (protons + neutrons) – Only 0.7%; 99.3% 238 U – Enrichment separates 235 U from 238 U – Fission chain reaction Nuclear bomb – Spontaneous fission of highly enriched 235 U – Self-amplifying Nuclear Reactors Sustain a continuous chain reaction – Some 238 U converts to 239 Pu, also undergoes fission – Geometric pattern • Moderator – Slows neutrons to correct speed for fission – Light-water reactors in U.S. Fuel rods – UO 2 loaded into long metal tubes – Radioactive spent-fuel elements replaced Control rods – Neutron-absorbing material – Help moderate chain reaction Nuclear Power Plants Boiling-water reactor – Circulate water through the reactor Pressurized-water reactor – Superheated reactor water is circulated to boil other water – Two-thirds in U.S. 1 2 1 2 3 4 5 1 2 6 1 2 7 1
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
2 Loss-of-coolant accident (LOCA) – Crack in reactor vessel – Core overheats •Meltdown: core materials melt •Steam explosion •Backup cooling systems; housed in thick concrete containment building Nuclear Power vs. Coal Power Fuel needed – Mining uranium vs. coal •Energy from 1 lb. uranium fuel = 50 tons coal energy environmental damage accidental deaths • CO 2 emissions – None from nuclear plants •Fossil fuels used: mining, enriching, construction, decommissioning of plants • SO 2 & other emissions – No acid-forming pollutants from nuclear • Radioactivity – 100x more from coal Solid wastes – 600,000 tons of ash from coal •Much reused for cement – 250 tons from nuclear •Highly radioactive wastes Nuclear Power vs. Coal Power • Accidents – Coal •Fatalities & destructive fire
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern