Blackout prevention 2

[marshall2]

FEMA? Emergency management? How about some emergency PREVENTION? Consider: if NO's levees had been maintained properly, if all of the pumps (not 30%) had been operable and if electrical power had been maintained the disaster probably would have just been a severe storm with minimal loss of life and property.

Questions for EEs in the power field: What would it take to harden the distribution system so that interuptions could be reduced from expected to seldom? What would it take to floodproof areas subject to floods? Blackouts take a huge toll; shouldn't security of these systems be mandated by law? Has anyone ever studied the finacial impact of power interuptions and hopefully compared it to the cost of prevention?

 

[rbulsara]

How about not building a city in "bowl" surrounded by water bodies? How much planning does that take?

 

[cuky2000]

There is not a simple isolated answer to this problem. The relocation of the city should not be rule out. However, this decision is not exclusively determined by electrical or technical factors.

One possible approach is assembling a multidisciplinary planning group to determine new environment requirement for building and all infrastructure. For brainstorm purposes, let’s say:
- Win speed: 250 mph
- Flow level: 10 ft above grade.

A technical and economical study should evaluate alternatives:
- Permanent Structure such as substation & power plants
- Build them in elevated platform above flow level.
- Install them in a floating barge.
- Construct seal vaults water tie
- Relocate all major generators and substation to a safe remote elevated area.

For transmission, line and distribution system only two options are available: reinforced overhead systems or build water-tie underground systems.

The use of modern technology combined with mobile systems may be part of the options to be considered.

 

[alehman]

The vast majority of the problems are in the distribution system and individual services. There was damage to transmission lines, but these can be repaired relatively quickly.

http://www.entergy.com/corp/EmergencyCtr/pictures.asp

From a Sept. 9 news article:
Entergy said it has 17 generating units in the New Orleans area fueled by natural gas and/or oil. The company has returned nine of those units to service, with another expected to return later this week. Despite the outages, the utility said generation capacity is sufficient to meet load and their fuel supplies are adequate.

This article that starts to address the question of hardening the power systems:

http://www.todaysengineer.org/2005/Sep/katrina.asp

 

[RonShap]

How about taking the Seattle approach.

http://historictraveler.away.com/primedia/pol_soc/underground_1.adp

Then bury as much infrastructure as you can.

 

[alehman]

Underground would no doubt reduce wind damage. When flooding occurs underground can be problematic also. The biggest issue with underground installations is the one that creates most engineering challenges - cost.

My company has studied total overhead to underground conversions for a few small cities in the miswest to improve reliability during winter ice storms. The cost is very high - due in large part to the intensive labor of working around all of the existing obstacles. The cost difference would be lower for new developemnts.

 

[alehman]

Not to be excessively pessimistic, I guess I would add that when existing conditions are suitable or economic incentive is sufficient, obviously it can and has been done. Maybe some areas of New Orleans would be in that category. Densely packed urban neighborhoods would be very costly to convert. Underground may make sense for areas that are to be completely re-built however.

 

[rbulsara]

underground only protects the cables, ..and that too against wind etc.

Flooding is totall different challange...plus what about the equipment such as substations, tranformer swithes..etc. whihc essentially are above grade or in below grade vaults but not safe from total flooding.

In a totally flooded city, first thing to be turned off is the electrictiy (and gas) for other safety reason. To even think that just availability of power over transmission lines would have helpd new orleans is naive. Any electricall hardening has to be acheived by local power generation, which is protected by flood and enuff fuel. The again no power is good if the pump motors and support systm itself is flooded. Plus you can pump leaks and seepage, not a rushing strom water due to leevy breaks..

If any thing, make leevy stronger..if at all necessary.

I am not too much imperssed with scientists/engineers making efforts to make stupid ideas like building city in bowl work , though. Much less someone blaming them.

For money, much of the things are possible, but sometime the question is why?Specailly if there is an alternative.

Every investment is based on its worth, ROI and takig some risks. Nothing is bulletproof in the universe.

 

[EEJaime]

Gentlemen,

I think that in the short term one of the solutions will be to underground as much of the infrastructure as possible. With the massive costs of the overall re-build, this will be a drop in the bucket. In the long term, planning to provide generating facilities outside the flood plane with distribution into the city, with major substations, etc..., perhaps on upper levels of some of the reconstructed buildings will be looked at. Along with code requirements for submersible switches, connections, etc... in the distribution systems. This city will not be relocated. The local, state and national political climate, and the simple economic realities will preclude any attempts at wholesale relocation. The historical preservationists will come unglued at the thought. At best we will get solutions to some of the most glaring problems, and as soon as the political and media "hot topic" focus is off, it will be back to the status quo.

It is not as if a city planner said, "hey, let's put a city in this hole!". This city, like most cities developed over a period of hundreds of years. People built where they could get land.

Here in California, local governments are granting development permits to developers even close to existing levees in the northern part of the state. Close to where this past year the state was ordered to pay out several billion dollars for a levee break which occurred about 15 years ago. The solution-when the state resources board started requiring environmental impact reports, and started opposing such development-well last week Governer Schartzenegger fired the entire board and appointed his own, "pro-business" board. Status Quo.

 

[dpc]

New Orleans is in a hole because it is sinking. Sinking accelerated after the huge Mississippi River levees were built after the 1927 flood.

The other point that needs to be made is that it does not make economic sense to design the electrical distribution system to withstand wind loads and other conditions that would destroy the vast majority of buildings being served.

 

[EEJaime]

I have seen satellite imagery of the entire gulf coast and if you compare that taken twenty years ago to the current images, you can see that vast areas are now below sea level. I have no idea what if anything can be done about it. I imagine the committees, commissions, boards, task forces, councils, etc..., which will be looking at this for the next couple of decades will have to make some difficult choices. And hopefully the many billions of dollars which will be going there will buy more than just 'studies'.

dpc, you are right that an infrasructure with nothing to serve is not very useful, but I think that at the very least, it can be hardened enough to enable it to continue to operate most of the critical facilities during and after these massive incidents. The lowest tier branches feeding directly to users will continue to require replacement/repair, however, with proper planning, maybe the entire structure won't suffer a massive melt-down as occured this time.

 

[rbulsara]

"Along with code requirements for submersible switches, connections, etc... "..what a concept!!!.

Underground facilites are most vulnerable to total flooding. Overhead facitlies are most vulnerable to winds. If you got both of them, nothing will help. Can't have both ways.

And when these things blow up when needed most blame the engineers who designed it. Not only expect the rest of the world to the rescue, which woudl not have been required, if the codes were made to not build critical infrastrucures in vulnerable place to begin with!!

Times where different 100's of years ago, today we have choices and ability to make wiser choices, make them.

 

[itsmoked]

I can imagine the 300MVA transformers up on stilts everywhere...Substations on 20 foot mounds. Beautiful!!

Actually that might be incentive to raise the surrounding stuff to improve the view.