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| Sun, 12-07-2008 - 1:31pm |
I understand our President Elect wishes to rebuild highways, bridges, schools, broadband, and other stuff.
Which sounds nice.
However the Eisenhower Highway system is already built. Most who want broadband have it. Most kids have a public school, which were generally available to all over a century ago.
Shouldn't a wise future looking leader seek to find things for us to do which create new capabilities for our country? Isn't rebuilding what we already have, not adding much to our infrastructure, economic or cultural capability?
If the argument is our roads, broadband, schools and what not are in such a disastrous state of repair that only a complete rebuild will prevent schools from collapsing on children ... then shouldn't we remove the current management structures which have created this mess?
Shouldn't we federalize the school system as an example. How about federalizing all highways? You know to assure stuff gets done right. I understand the NYC MTA is in trouble, how about we just federalize all mass transit. I mean it's not like there has ever been any mismanagement at Amtrak!



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Really?
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Really?? So is mine!
:o)
Awesome! What instrument/major?
Mine is a guitar performance/songwriting major. He is self taught on the electric guitar. Nice to have him away at school and have a peaceful house for a bit! LOL!
Sopal
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Some info about the power blackout in 2003. I know that as soon as it happened many in the US quickly jumped on the bandwagon and blamed Canada (as our power grids are shared and much of the electric power going to the US comes from Canada)....Hilary Clinton was quick off the mark to point fingers at Canada. She's done that before...with insinuating that terrorists came in through Canada etc....only to be proven wrong (however, retractions rarely get coverage and the myths persist)...Anyway....Here's some info on that:
http://en.wikipedia.org/wiki/Northeast_Blackout_of_2003#Causes
Causes
Background
Electrical power cannot easily be stored over extended periods of time, and is generally consumed less than a second after being produced. The demand load on any power grid must be matched by the supply to it and its ability to transmit that power. Any great overload of a power line, or underload/overload of a generator, can cause hard-to-repair and costly damage, so the power grid is disconnected if a serious imbalance is detected.
Power lines normally grow longer and sag between their towers when they get hotter as they carry more power, reaching a designed lowest height above the ground at a specified power level. To prevent the sagging lines from coming too close to trees and causing a short circuit (which can cause a forest fire), the trees are pruned, often on a five-year cycle. If the lines touch the trees, they are disconnected by systems which detect the sudden change in power flow from the short circuit.
These power changes from a line going out of service can sometimes cause cascading failures in the areas around them as other parts of the system see the fluctuations. These are normally controlled by delays built into the shutdown processes and by robust power networks with many alternative paths for power to take, which has the effect of reducing the size of the ripples. The borders of the blacked out areas on 14 August were where the blackout areas encountered systems with more spare capacity.
The operators of the power system control center are responsible for ensuring that they balance the supply of power, the loads (customers demanding that power), and the transmission line capacity, so that their system is in a state where no single fault can cause it to fail. After a failure affecting their system, operators are required within thirty minutes to obtain more power from generators or other regions or to shed load (meaning cut power to some areas), until they can be sure that the worst remaining possible failure anywhere in the system will not cause an unplanned system collapse. In an emergency they are expected immediately to shed load as required to bring the system into balance.
To assist the operators there are computer systems, with backups, which issue alarms when there are faults on the transmission or generation system. Power flow modeling tools let them analyze the current state of their network, predict whether any parts of it may be overloaded, and predict what the worst possible failure left is, so that they can change the distribution of generation or reconfigure the transmission system to prevent a failure should this situation occur. If the computer systems and their backups fail, the operators are required to monitor the grid manually, instead of relying on computer alerts. If they cannot interpret the current state of the power grid in such an event, they are to invoke a contingent operational pattern. If there is a failure, they are also required to notify adjacent areas which may be affected, so those can predict the possible effects on their own systems.
Backing up the local operators are regional coordinating centers which bring together information from adjacent areas and perform further checks on the system, looking for possible failures and alerting operators in different systems to them.
Investigation efforts
A joint federal task force was formed by the governments of Canada and the U.S. to oversee the investigation and report directly to Ottawa and Washington. The task force was led by then-Canadian Natural Resource Minister Herb Dhaliwal and U.S. Energy Secretary Spencer Abraham.
In addition to determining the initial cause of the cascading failure, the investigation of the incident also included an examination of the failure of safeguards designed to prevent a repetition of the Northeast Blackout of 1965. Issues of failure to maintain the electrical infrastructure, failure of upgrading to so-called "smart cables," failure of shunting and rerouting mechanisms, AC vs. DC intersystem ties, and substitution of electricity market forces for central planning were expected to arise. The North American Electric Reliability Corporation, a joint Canada-U.S. council, is responsible for dealing with these issues.
On November 19, 2003, Energy Secretary Spencer Abraham said his department would not seek to punish FirstEnergy Corp for its role in the blackout because current U.S. law does not require electric reliability standards. Abraham stated, "The absence of enforceable reliability standards creates a situation in which there are limits in terms of federal level punishment."
Findings
In February 2004, the U.S.-Canada Power System Outage Task Force released their final report, placing the main cause of the blackout on FirstEnergy Corporation's failure to trim trees in part of its Ohio service area. The report said that a generating plant in Eastlake, Ohio (a suburb of Cleveland) went offline amid high electrical demand, and that strained high-voltage power lines (located in a distant rural setting) later went out of service when they came in contact with "overgrown trees". The cascading effect that resulted ultimately forced the shutdown of more than 100 power plants.
Computer failure
The Task Force also found that FirstEnergy did not take remedial action or warn other control centers until it was too late, because of a software bug in General Electric Energy's Unix-based XA/21 energy management system that prevented alarms from showing on their control system. This alarm system stalled because of a race condition bug. After the alarm system failed silently without being noticed by the operators, unprocessed events (that had to be checked for an alarm) started to queue up and the primary server failed within 30 minutes. Then all applications (including the stalled alarm system) were automatically transferred to the backup server, which also failed due to the same reason as the primary one. After this time (14:54), all applications on these two servers stopped working. Another effect of the failing servers was that the screen refresh rate of the operators' computer consoles slowed down from 1-3 seconds to 59 seconds per screen.
Sequence of events
Blackout sequence of events, August 14, 2003 (times in EDT):
* 12:15 p.m. Incorrect telemetry data renders inoperative the state estimator, a power flow monitoring tool operated by the Ohio-based Midwest Independent Transmission System Operator (MISO). An operator corrects the telemetry problem but forgets to restart the monitoring tool.
* 1:31 p.m. The Eastlake, Ohio generating plant shuts down. The plant is owned by FirstEnergy, an Akron, Ohio-based company that had experienced extensive recent maintenance problems.
* 2:02 p.m. The first of several 345 kV overhead transmission lines in northeast Ohio fails due to contact with a tree in Walton Hills, Ohio.
* 2:14 p.m. An alarm system fails at FirstEnergy's control room and is not repaired.
* 2:27 p.m. A second 345 kV line fails due to contact with a tree.
* 3:05 p.m. A 345 kV transmission line known as the Chamberlain-Harding line fails in Parma, south of Cleveland, due to a tree.
* 3:17 p.m. Voltage dips temporarily on the Ohio portion of the grid. Controllers take no action.
* 3:32 p.m. Power shifted by the first failure onto another 345 kV power line, the Hanna-Juniper interconnection, causes it to sag into a tree, bringing it offline as well. While MISO and FirstEnergy controllers concentrate on understanding the failures, they fail to inform system controllers in nearby states.
* 3:39 p.m. A FirstEnergy 138 kV line fails.
* 3:41 p.m. A circuit breaker connecting FirstEnergy's grid with that of American Electric Power is tripped as a 345 kV power line (Star-South Canton interconnection) and fifteen 138 kV lines fail in rapid succession in northern Ohio. Later analysis suggests that this could have been the last possible chance to save the grid if controllers had cut off power to Cleveland at this time.
* 3:46 p.m. A sixth 345 kV line, the Tidd-Canton Central line, trips offline.
* 4:06 p.m. A sustained power surge on some Ohio lines begins an uncontrollable cascade after another 345 kV line (Sammis-Star interconnection) fails.
* 4:09:02 p.m. Voltage sags deeply as Ohio draws 2 GW of power from Michigan, creating simultaneous undervoltage and overcurrent conditions as power attempts to flow in such a way as to rebalance the system's voltage.
* 4:10:34 p.m. Many transmission lines trip out, first in Michigan and then in Ohio, blocking the eastward flow of power around the south shore of Lake Erie. Suddenly bereft of demand, generating stations go offline, creating a huge power deficit. In seconds, power surges in from the east, overloading east-coast power plants whose generators go offline as a protective measure, and the blackout is on.
* 4:10:37 p.m. The eastern and western Michigan power grids disconnect from each other. Two 345 kV lines in Michigan trip. A line that runs from Grand Ledge to Ann Arbor known as the Oneida-Majestic interconnection trips. A short time later, a line running from Bay City south to Flint in Consumers Energy's system known as the Hampton-Thetford line also trips.
* 4:10:38 p.m. Cleveland separates from the Pennsylvania grid.
* 4:10:39 p.m. 3.7 GW power flows from the east along the north shore of Lake Erie, through Ontario to southern Michigan and northern Ohio, a flow more than ten times greater than the condition 30 seconds earlier, causing a voltage drop across the system.
* 4:10:40 p.m. Flow flips to 2 GW eastward from Michigan through Ontario (a net reversal of 5.7 GW of power), then reverses back westward again within a half second.
* 4:10:43 p.m. International connections between the United States and Canada begin failing.
* 4:10:45 p.m. Northwestern Ontario separates from the east when the Wawa-Marathon 230 kV line north of Lake Superior disconnects. The first Ontario power plants go offline in response to the unstable voltage and current demand on the system.
* 4:10:46 p.m. New York separates from the New England grid.
* 4:10:50 p.m. Ontario separates from the western New York grid.
* 4:11:57 p.m. The Keith-Waterman, Bunce Creek-Scott 230 kV lines and the St. Clair-Lambton #1 and #2 345 kV lines between Michigan and Ontario fail.
* 4:12:03 p.m. Windsor, Ontario and surrounding areas drop off the grid.
* 4:13 p.m. End of cascading failure. 256 power plants are off-line, 85% of which went offline after the grid separations occurred, most due to the action of automatic protective controls.
Sopal
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Jazz guitar (though he also plays Sax). He's going to a university in our city so he is living at home. I've still got numerous guitars and cases leaning up here and there around the house....broken strings tangled and hanging out of garbage cans, thumb picks turning up in the dryer, amps in the front hallway and that unmistakable plink plink plink as the ubiquitous background noise of someone practicing on an electric guitar that isn't plugged in.
However, I don't mind it all that much. :o)
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