Wes Carter
EF5
Dave, well said. You nailed it. I'm not a big fan of BWR's either. It's one thing to have to watch a sight glass on a boiler so you don't burn tubes, it's another thing to have to maintain a water level to keep nuclear fuel from melting. Also, keeping the primary coolant system pressurized mitigates steam impingement and pitting which greatly increases the life of the primary coolant lines, the reactor feedwater pumps, and everything. Also, chemistry control is much easier because you don't have to consider the steam side and the condensate side separately. It's all one big loop of water.
Of course you have to deal with those issues on the secondary system, but on that side you don't have (unless you have ruptured steam generator tubes) any contamination in that loop. So you just treat it like you would any steam cycle, except that you monitor it for contamination and you don't shut it down because ultimately it is removing the heat from the primary loop. But the design is much more forgiving even if it is a bit more inefficient than the BWR.
Although PWR's are more expensive initially, they are cheaper to operate in the long run. So the old adage "pay a little now or a lot later" rings true with Boiling Water Reactors versus Pressurized Water Reactors.
Of course you have to deal with those issues on the secondary system, but on that side you don't have (unless you have ruptured steam generator tubes) any contamination in that loop. So you just treat it like you would any steam cycle, except that you monitor it for contamination and you don't shut it down because ultimately it is removing the heat from the primary loop. But the design is much more forgiving even if it is a bit more inefficient than the BWR.
Although PWR's are more expensive initially, they are cheaper to operate in the long run. So the old adage "pay a little now or a lot later" rings true with Boiling Water Reactors versus Pressurized Water Reactors.