Best war of current t-shirt I have ever seen.....

WBahn

Joined Mar 31, 2012
29,978
I think that any new installations that require a long distance transmission are going to consider DC, there are incredible savings to be had, with the loss of one conductor and the much reduced losses.
Max.
My understanding is that a major savings is actually the cost of the land right-of-way leases since it can be significantly narrower for a DC monoline.
 

cmartinez

Joined Jan 17, 2007
8,218
The 3 HVDC conversion stations we presently have were built in 1968.
Presently there is a total of 5 Hydro stations with 15 Hydro generators capable of producing 5,700Mw.
Another new one in the works.
Max.
Was the necessary semiconductor technology available even back then? And if so, why has it taken so long for it to become more popular?
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
I would have to check with my neighbour, the Hydro engineer.
But he did tell me he was involved when they used Ignitron tubes, prior to SS.
I think it has been popular for a while, just that it is only feasible for a long distance transmission line.
Max.
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
My understanding is that a major savings is actually the cost of the land right-of-way leases since it can be significantly narrower for a DC monoline.
There are environmental considerations, especially when traveling through arboreal forest.
Max.
 

BR-549

Joined Sep 22, 2013
4,928
AC is just manipulated DC. You can think of DC as male and AC as female. There are thousands of studies confirming this theory and these characteristics.
 

tcmtech

Joined Nov 4, 2013
2,867
Also, you speak like engineers and business people running the utility are stupid.
Obviously that's a perception problem on behalf of your own personal biases towards what you read. :(

I however made no claims of any kind. I simply demonstrated a commonly used mathematical slight of hand technique that is commonly used for deceptive marketing and PR purposes to make very small and often times questionably justifiable gains look like well justified ones though simple numerical slight of hand.

A concept that should be a painfully obvious one given the present way or mass media and general governing bodies report things to the public to justify highly questionable actions on their behalf.

Kinda sad that what you say strongly suggests you may have both highly biased and very poor understanding of this sort of junior high school level mathematical concepts. :oops:
 

tcmtech

Joined Nov 4, 2013
2,867
It is generated in the usual way (AC) the conversion takes place either end.
Yes, over many Km the saving in the one less line is also considerable.
ABB were one of the first to install in the west quite a few decades ago.
Max.
Yea we have a large DC transmission line going through our state not too many miles south of me. It's been there a long time now.

By the numbers the power density for the equivalent amount of cabling used is impressive but the conversion systems and relative difficulty in setting up a utility scale HVDC power line system to work in a omni directional feed/load distribution capability, that's bonehead simple on a multiphase AC system due to the simple inherent bidirectional working capacity of iron core transformers, is one of its largest present downsides.

http://solarec-egypt.com/resources/Larruskain_HVAC_to_HVDC.pdf

http://electrical-engineering-portal.com/8-main-disadvantages-of-hvdc-transmission

http://www.theenergycollective.com/roger_rethinker/204396/ac-versus-dc-powerlines

http://large.stanford.edu/courses/2010/ph240/hamerly1/docs/energyweek00.pdf

By the numbers what each cost to instal and operate. (Watts for watts DC isn't comparatively cheaper until power and distance values get really big to say the least.)

https://www.wecc.biz/Reliability/2014_TEPPC_Transmission_CapCost_Report_B+V.pdf

http://electrical-engineering-porta...high-voltage-direct-current-hvdc-transmission

Basically until you start pushing Gigawatt and higher power transfer levels at distances greater than 500+ miles DC is not cheaper than AC. :(
 

JoeJester

Joined Apr 26, 2005
4,390
If there is money to be save, they will invest.
I agree. The speed of the investment can be faster if the benefits still exist when you must invest in more infrastructure before the current infrastructural has reached it's life-cycle.

Every new year the vehicles have "more benefits" or "gadgets." Not too many people are purchasing a new car every year. Even the government, will wait 5 years or 60k miles before getting a new 4x4.
 

cmartinez

Joined Jan 17, 2007
8,218
Even the government, will wait 5 years or 60k miles before getting a new 4x4.
Yeah... but then they'll buy it at a price equivalent of a $(4x4)^(4x4) ....

EDIT: Just to clarify... (4x4)^(4x4) = 16^16 = $18,446,744,073,709,551,616.00 ... and that's not counting the extended warranty fee...
 

killivolt

Joined Jan 10, 2010
835
GSA, the supplier of the U.S. government would rather buy new tires than do a front end alignment.
But, running 5 years and selling it to the public, individual A obtain the Vehicle at reduced price. Then B purchases it and runs the rubber off and put another set on and sell it to the next guy C, who purchases it at an even more reduced cost.

You get it :D by the time it reaches me. I pick it up for $1000 dollars then drive it into the ground then sell it for scrap metal.

92 Buick lesabre 144k new tires luxury with the money I save I put in the tank. :)

kv

Edit: Uh, and AC/DC :D
 
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tcmtech

Joined Nov 4, 2013
2,867
You get it :D by the time it reaches me. I pick it up for $1000 dollars then drive it into the ground then sell it for scrap metal.

Same here. I cant say how many times I have been lectured by certain types of people for 'ruining my vehicles resale value' by doing such and such modification to them to improve something or add something to them.

BS. The scrap man pays by the pound and couldn't care less what I did to my vehicle before it showed up in his yard. :p
 

justtrying

Joined Mar 9, 2011
439
In engineering speak we call this the point of deminishing returns - but thanks for the math.

Also, you speak like engineers and business people running the utility are stupid. If there is money to be save, they will invest. If there is no money to be saved, they will find another location to spend the money. I'm sure you will fire back with various conspiracy theories and superficial examples about unprofitable projects but cash is king and grid reliability or other less obvious goals impact the cash a utility makes. I'm certain their decisions have merit.
If the project is being done by BC Hydro or in Ontario, I will be questioning the numbers a lot
 

justtrying

Joined Mar 9, 2011
439
That's your prerogative. Do you care to share why? Do note that my statement included: "...reliability or other less obvious goals".

I await details.
Yes, it was a bit of a gut reaction...

Unfortunately for us (I will speak more to BC Hydro as it is what I know, but I understand that Ontario is even worse) BC hydro is a public entity and is a very bad deal...

All of its projects are notorious for poor management and cost over-runs. In general, if they try to sell us something, further scrutiny is required.

https://www.pressreader.com/canada/vancouver-sun/20150423/281672548485394
http://globalnews.ca/video/1958480/substandard-steel-plagues-bc-mega-projects

The current one of course is site C dam which is set to flood one of our biggest valleys. The controversy around it is the fact that electricity is not really needed by the province. They tried to say that it will be needed by the upcoming LNG projects (none of which are happening anytime soon and those plants typically generate their own electricity), then they said they would sell excess power to Alberta, then they said...

I know this is an opinion piece, but sadly the facts are true - https://thetyee.ca/Opinion/2016/09/12/BC-Hydro-Public-Interest-Private-Profits/
 
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