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Fascinating distribution system: Pitcairn Island

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Thanks for the video Eleanor!

I'm glad you posted this thread, it reminds me of remote buildings/facilities/camps which must generate their own power.

Something like this would also work really well for Pitcarin Island:


Local_Power_vb8hhb.jpg



I'd imagine the current setup is very similar.



 
I'm surprised they can't parallel those generators. Seems trivial enough to prevent annoying blinks multiple times a day. I can imagine them switching to a smaller generator later at night to keep the efficiency up.

Needs something like a 60kW inverter generator system where the generator(s) run at the minimum power demand speed.

Keith Cress
kcress -
 
itsmoked (Electrical) wrote:
5 Feb 21 02:54
I'm surprised they can't parallel those generators. Seems trivial enough to prevent annoying blinks multiple times a day. I can imagine them switching to a smaller generator later at night to keep the efficiency up.

Needs something like a 60kW inverter generator system where the generator(s) run at the minimum power demand speed.

Keith Cress
kcress -
Eleanor White replying:

Just a guess, but I suspect the inability to parallel
the generators was a decision to avoid the extra time
and equipment, possibly being seen as "unnecessary."

Currently, the power system is stopped from 10 p.m.
to 6 a.m., although the attachment to my original post
mentions that 24-hour service is a goal of the
proposed upgrade.

Currently, they have a small 12 KW generator to keep
the clinic supplied with power around the clock.

Eleanor White
 
Ah. We just finished watching that lovely dentist video 5 minutes ago where I just caught that 10-6 blackout.

That would be such a blast to get them up with solar. Getting fuel there must be pretty miserable.

Keith Cress
kcress -
 
Here's a nice, compact summary about life
on Pitcairn, including links to two newsletters:


Apparently they do have satellite-linked TV and
Internet.

The electricity rates appear pretty darn high,
from that page linked above:

Power costs as of January 2013
UNITS COST PER UNIT - NZ$
Up to 210 0.60
between 210 and 250 0.85
Greater than 250 0.90

I'm assuming a "unit" is a KWH.

By contrast, my electricity costs here in Ontario,
Canada (Canadian dollars) are:

On peak 0.217Here's a nice, compact summary about life
on Pitcairn, including links to two newsletters:


Apparently they do have satellite-linked TV and
Internet.

The electricity rates appear pretty darn high,
from that page linked above:

Power costs as of January 2013
UNITS COST PER UNIT - NZ$
Up to 210 0.60
between 210 and 250 0.85
Greater than 250 0.90

I'm assuming a "unit" is a KWH.

By contrast, my electricity costs here in Ontario,
Canada (Canadian dollars) are:

On peak 0.217Here's a nice, compact summary about life
on Pitcairn, including links to two newsletters:


Apparently they do have satellite-linked TV and
Internet.

The electricity rates appear pretty darn high,
from that page linked above:

Power costs as of January 2013
UNITS COST PER UNIT - NZ$
Up to 210 0.60
between 210 and 250 0.85
Greater than 250 0.90

I'm assuming a "unit" is a KWH.

By contrast, my electricity costs here in Ontario,
Canada (CDN$ ~ 1.09 x NZ$) are:

On peak 0.217 ... or ~0.20 NZ$
Mid peak 0.15 ... or ~0.14 NZ$
Off peak 0.105 ... or ~0.10 NZ$

Comparing the two "mid" rates, an electric bill
here in Ontario would be about 6 times higher
on Pitcairn! (Candles start looking good!)

Eleanor White
 
Somewhat interesting side note to all of this. If you do the Google maps thing for the inhabited island and do a "street view", what you get is apparently something done by an independent contractor, not Google themselves, because that contractor did NOT remove himself from the view like Google does with their mapping vehicles. Point the view straight down and you see a couple of dudes on an ATV holding the GPS mapper. You'll notice it pops up with a link to the guy that provided it as a "local guide" and the company that made the GPS mapper too.



Elanor said:
I'd love to know how they handle electric power, water
and sewage at that very high place. Anyone know?
Can't say for sure because it will vary depending on what they might have available. For most ski chalets that have a lift system, power is run parallel with the lift cable systems. Some use SWER (Single Wire Earth Return) systems if the distance is extreme, I worked on one in the high Sierra Nevada mountains that was like that for years (Dodge Ridge) before being upgraded. As to water, most places like that get their water from the snow and store it if they remain open in the summer. Sewage is usually handled by any number of micro-sewage treatment systems and in many cases, the resulting solids are spread to the local forests and wastewater is run through an RO system and reused.


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
 
stevenal said:
1 Feb 21 15:08
How did you get 2,400/4,160? When I zoom in to the insulators, they appear quite small.

I thought I'd post an example of a small insulator installed on a recently-set pole here in northern Ontario Canada. The system is 12,470/7,200 volts:

image_z85z7n.png


That's what I meant when I thought I'd seen some rather slender high voltage insulators, probably some sort of rubber molded around a fiberglass rod.

Eleanor
 
Does your area have 27.6kv distribution? I know that is really popular in some parts of Canada.
 
Mbrooke said:
Does your area have 27.6kv distribution? I know that is really popular in some parts of Canada.
.
I'm in a wilderness village, and at an age where I don't travel, so I'm not sure about my general area, but my village uses 12,470/7,200 domestic.

Eleanor White
 
Wilderness village - probably like Elliot Lake or something...there are scads of them, and they're dotted everywhere, although far-flung in many instances...

27.6 kV [ which usually translates into 28 - 29 kV at the transformer station busses due to feeder voltage drop ] distribution voltage is HUGELY popular in Ontario, since there are far less engineering challenges to connecting 16 kV single-phase transformers directly to the feeders. 44 kV on the other hand [ which usually translates into 45 - 46 kV at the transformer station busses ] is almost never used to supply small customers directly, instead distribution stations step the 44 down to whatever distribution voltage prevails in any given area - typically from as low as 4800/8320 to 8 kV/13.8 kV, with a few steel mills receiving power directly at a giddy 8.6 kV / 14.4 kV. The voltage harnessed can often be attributed to legacy installations acquired by Ontario Hydro piecemeal, and therefore without prior standard.

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]
 
Actually , 12.47 kV is quite common, even in the US. Although some utilities us 13.2Kv and even 13.8 kV. Which all are 15 kV class.

Having worked for a utility that in three states had several different distribution voltages, none of these are uncommon.
 
27.6kv is rare in the US, even as hold over subtransmission. On the other hand 27.6kv is common in parts of Canada.
 
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