Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Olkiluoto-3 EPR, Finland

  1. Mar 31, 2005 #1


    User Avatar
    Staff Emeritus
    Science Advisor


    Plant's net electric output approx. 1600 MW
    Net efficiency approx. 37 %

    Nuclear News, March 2005
    Last edited by a moderator: Apr 21, 2017
  2. jcsd
  3. Mar 31, 2005 #2
    Is 37% net efficiency high for reactors?
  4. Mar 31, 2005 #3


    User Avatar
    Science Advisor


    Yes - that's good for a reactor.

    Fossil fueled plants will do about 40%

    The 2nd Law of Thermodynamics puts limits on the efficiency of a
    heat engine - which the Rankine steam cycle in any power plant is.

    The hotter the source of heat - the more efficient the steam cycle can
    be. Nuclear reactor output temperatures are limited to about 650 F
    for a Pressurize Water Reactor [ PWR ].

    The output temperature of a fossil fueled boiler is in the neighborhood
    of 1000 F. So fossil plants have more efficient steam cycles.

    The now shutdown Indian Point Unit 1, near Peekskill, NY; had an
    oil-fired superheater to heat the steam out of the reactor, in order
    to gain efficiency.

    High temperature gas-cooled reactors can approach the efficiencies
    of fossil plants. The only 2 HTGRs in the USA were Peach Bottom 1,
    and Fort Saint Vrain, both shutdown. The Germans were experimenting
    with high temperature gas cooled pebble bed reactors.

    Dr. Gregory Greenman
  5. Mar 31, 2005 #4


    User Avatar
    Staff Emeritus
    Science Advisor

    In the early 1990's Siemens introduced some advanced blade designs into their steam turbines. The blades were curve rather than straight, seals were improved to reduce by-pass, and stages were optimized. The net result is that a plant that was designed for 1450 MWe with the old turbine design (~33.5% efficient) can now produce 1600 MWe with the same thermal energy, thus realizing a 37% efficiency.

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook