Alaskan microgrids offer energy resilience and independence

December 26, 2017, American Institute of Physics
Wind turbines supply renewable energy to microgrids across Alaska. Credit: Chris Pike, the Alaska Center for Energy and Power, University of Alaska Fairbanks

The electrical grid in the contiguous United States is a behemoth of interconnected systems. If one section fails or is sabotaged, millions of citizens could be without power. Remote villages in Alaska provide an example of how safeguards could build resilience into a larger electrical grid. These communities rely on microgrids—small, local power stations that operate autonomously. Nine articles in the recent issue of the Journal of Renewable and Sustainable Energy, from AIP Publishing, provide the first reviews of energy technologies and costs for microgrids in Alaska.

"The integration of renewable resources into microgrids is an active area of research," Erin Whitney, a researcher at the Alaska Center for Energy and Power, University of Alaska Fairbanks said. "Alaskan are at the forefront of thinking about integrating sustainable, local, and often renewable, energy into their power generation portfolios."

Unlike the Lower 48, Alaska's terrain makes it difficult and cost prohibitive to establish a large-scale electrical grid. Instead, microgrids provide permanent, self-sufficient islands of electricity that can produce up to 2 megawatts of electricity for remote communities. Alaskan microgrids provide electricity for more than 200 communities and generate more than 2 million hours of operating experience annually.

Reducing energy costs is the driving factor for implementing renewable energy in remote grids. According to Whitney, many Alaskan communities are motivated to find local energy solutions to reduce the cost of shipping expensive diesel fuel to power their microgrids.

"Some communities are so remote that they can only get fuel delivered once or twice a year when the ice melts and a barge can move up the river," Whitney said. "This situation translates into some of the highest energy costs in the nation."

Whitney explains that oil and local, renewable resources can work in tandem to supply electricity to microgrids. A diesel generator typically provides base power generation, while renewable energy sources reduce the load on the generators and save fuel, lowering energy .

Even above the Arctic Circle, where the region is cloaked in darkness for a portion of the year, communities harness seasonal renewable resources by switching between solar power during summer months and wind power during the winter months.

During the past decade, Alaska has invested over $250 million to develop and integrate renewable projects to power systems.

Whitney hopes the information compiled in the collection of papers will help educate other communities about the value of integrating microgrid technology into a larger system to build resilience. Furthermore, Whitney hopes that microgrids will become a source for smaller remote communities around the globe.

"Alaska is its own place," Whitney said. "We [would love to share our] expertise with microgrids and data from microgrid systems with communities whether they are in the Arctic or not, and we hope to learn from others experience as well."

Explore further: Going off-grid easier with friends

More information: Erin Whitney, Preface: Technology and cost reviews for renewable energy in Alaska: Sharing our experience and know-how, Journal of Renewable and Sustainable Energy (2017). DOI: 10.1063/1.5017516

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betterexists
1.8 / 5 (5) Dec 26, 2017
Why NOT Everest-High Wind Turbines with Series of Blades all along the Pillars of them ?
WHAT IS WRONG WITH THAT ?
Why Not Put Graphene to use Also?
mackita
2.3 / 5 (6) Dec 26, 2017
During the past decade, Alaska has invested over $250 million to develop and integrate renewable energy projects to power microgrid systems
How much energy it got back for it? How such energy production is reliable?
gkam
2.1 / 5 (7) Dec 26, 2017
Save the questions - the contest is over, and we only wait for the cleaning up of the losers. It will take some time since these are infrastructure investments which take long lead times.

mackita
1.8 / 5 (5) Dec 26, 2017
This is just the question, who is the loser here: the wind plants are of limited life-time and they need backup anyway. How much coal their installation, maintenance and recycling these plants would need and how much energy they will generate during their lifetime? The net energy balance and economy decides, who is actual winner - not the people who managed to sell their work in the name of "renewable" ideology there.
gkam
2.7 / 5 (7) Dec 26, 2017
I am a former utility engineer. You apparently are unaware of the intellectual and financial rigor these large investments must endure before any commitment is made.
mackita
2.6 / 5 (5) Dec 26, 2017
Alaska's Energy Frontier Has 6x More Oil and Gas Than Thought versus Make Alaska Russian Again

You apparently are unaware of the intellectual and financial rigor these large investments must endure before any commitment is made.
Show us these numbers after then. Christopher Hitchens Razor: "What can be asserted without evidence can be dismissed without evidence,"
gkam
2.3 / 5 (6) Dec 26, 2017
The evidence is in the picture of the operating systems.

Ignorance of how the economics work is not proof that it does not.
mackita
2.1 / 5 (7) Dec 26, 2017
The evidence is in the picture of the operating systems.
This is just the famous fallacy of "enviromentalists": "The fact that some construction stands and replaces coil doesn't imply it actually saves the coil". One you start to argue with pictures, it's evident, you're also became a victim or this fallacy. And once you're calling yourself "an utility engineer", then it's even evident from where your occupational bias originates: you're someone like the coal baron who advocates the burning of coal.
Ignorance of how the economics work is not proof that it does not.
The economics work through massive governmental subsidizes, which often have origin in ideology not actual savings. That means, the economy of Alaskan microgrids program may look justified by governmental subsidizes - but it still doesn't mean, it's really money and coal saving. From this reason I'm looking for hard numbers, not fancy pictures of wind mills.
gkam
2.3 / 5 (6) Dec 26, 2017
" And once you're calling yourself "an utility engineer", then it's even evident from where your occupational bias originates: you're someone like the coal baron who advocates the burning of coal."

Save the hate. I was a Senior Engineer in Technical Services, involved with customer efficiency and increasing our alternative energy footprint. I was hired in 1980 despite my professed opposition to the two nuclear reactors being built by the company.

My loyalty is to efficacy and sustainability, not a company or fuel.

What is your education and experience in utility operations?
arcmetal
not rated yet Dec 26, 2017
Finally. And in the end a completely decentralized power grid (or rather no grid at all) will be the easiest solution. Just like what the engineers of the late 19th century had envisioned.

The lunacy of the last century will be forgotten, just like the push carts without wheels.
gkam
1 / 5 (4) Dec 26, 2017
"The lunacy of the last century will be forgotten, just like the push carts without wheels."

Your pushcarts have no wheels?

Where do you live?
Whydening Gyre
5 / 5 (1) Dec 26, 2017
I dunno...
I'm kinda likin' those Toshiba (or was it Mitsubishi) micro nuke plants (the 4S) that ya just bury in a deep hole and use it for the next however many years they last. It we still don't have fusion by the time it runs out - bury another one...
gkam
1 / 5 (4) Dec 26, 2017
Out of sight, out of mind.

Nuclear waste philosophy.
unrealone1
2.5 / 5 (6) Dec 27, 2017
Oldest commercial wind farm in Canada headed for scrapyard after 23 years
http://calgaryher...23-years
Every 20 years all turbines have to be replaced..At what cost?
gkam
1.8 / 5 (5) Dec 27, 2017
What was the wind turbine technology 20 years ago? Read the story and see the prime reason was safety.

What will they be replaced with? More Wind Turbines.
WillieWard
1.7 / 5 (6) Dec 27, 2017
"Renewable energy is a scam. There is no nicer way to put it."
"Green Activists Withdraw Adverts Which Falsely Claim Price Of Wind Energy Has Fallen By 50 Per Cent"
http://www.dailym...rms.html
https://www.thegw...er-cent/
gkam
1.8 / 5 (5) Dec 27, 2017
That was not even a good try, Willie. Science from the Daily Mail? Really?

Want to see the latest news from Fukushima?
doogsnova
1 / 5 (1) Dec 27, 2017
Deep geothermal is the only long term, round the clock, SAFE, renewable source of clean energy.
antialias_physorg
4.8 / 5 (5) Dec 27, 2017
Geothermal has its own problems. You're locally cooling the area which causes stresses in the crust...which in turn can facilitate earthquakes. Basel geothermal powerplant was shut down because it is suspected that the aggravate earthquakes.

Other renewables are plannable. The year-round yield of solar and wind is fairly constant. Coupled with a modicum of storage these two alone can give any country 100% energy independence.
Whydening Gyre
5 / 5 (3) Dec 27, 2017
Geothermal has its own problems. You're locally cooling the area which causes stresses in the crust...which in turn can facilitate earthquakes. Basel geothermal powerplant was shut down because it is suspected that the aggravate earthquakes.

Other renewables are plannable. The year-round yield of solar and wind is fairly constant. Coupled with a modicum of storage these two alone can give any country 100% energy independence.

Agreed. However, a modest amount of fossil fuels, nuclear and geothermal should be an acceptable contribution to the overall picture - 'til the fusion gorilla enters the room...:-)
TrollBane
5 / 5 (4) Dec 27, 2017
"Oldest commercial wind farm in Canada headed for scrapyard after 23 years
http://calgaryher...23-years
Every 20 years all turbines have to be replaced..At what cost?

Do you raise the same issue with a twenty year old car? A five year old computer? Didn't think so. So, Siegfried, it's the old double standards in the criticism trick. That's the second time I (wasn't) fooled by it this month.
TrollBane
5 / 5 (2) Dec 27, 2017
"fusion gorilla"
I, for one, welcome our new fusion-powered gorilla overlords. It's a nice change from hailing those ants. ;)
unrealone1
2.7 / 5 (7) Dec 27, 2017
Every 20 years your wind farms have to be replaced, 1 million turbines replaced every 20 years for the USA, staggering number.
Electric motors Dirty secret.
This toxic lake poisons Chinese farmers,
http://www.dailym...ale.html
WillieWard
2 / 5 (4) Dec 27, 2017
"Why do the sort of people who exclude nuclear energy for its radiation embrace geothermal?"
https://pbs.twimg..._6l_.jpg
https://pbs.twimg...0NRJ.jpg
gkam
1 / 5 (4) Dec 27, 2017
More "science" from the Daily Mail?
Why?? No science section in the National Enquirer?

unrealone1
3 / 5 (6) Dec 27, 2017
Rare-earth mining in China comes at a heavy cost for local villages
https://www.thegu...ollution
CLEAN ENERGY?
USA needs about 1 million Turbines to go "Green", the pollution caused by mining and manufacturing Rear Earth Magnets would be?
mackita
3.4 / 5 (5) Dec 27, 2017
Every 20 years all turbines have to be replaced..At what cost? Do you raise the same issue with a twenty year old car?
Car isn't supposed to generate energy. The turbine must create all energy required for its production, installation, maintenance and full recycling during its life time. In addition, it musts do it in sustainable way - for example its metals must get fully recycled and the energy introduced into it must get also accounted into it. Once it cannot do it, then it contributes to global warming instead of eliminating it and what's worse - it's not more sustainable, than the coal mining. Therefore the life-time of wind plants is critical for their environmentalism - this is simple arithmetic.
Whydening Gyre
5 / 5 (1) Dec 27, 2017
Every 20 years all turbines have to be replaced..At what cost? Do you raise the same issue with a twenty year old car?
Car isn't supposed to generate energy. The turbine must create all energy required for its production, installation, maintenance and recycling during its life time. Once it cannot do it, then it contributes to global warming instead of eliminating it. Therefore its life-time is important - this is simple arithmetic.

Good point, Mack. Anybody have any number to show that 20 yrs of a turbines life produces more energy than it took to create, install, maintain and decommission it it?
mackita
3 / 5 (4) Dec 27, 2017
"Green Activists Withdraw Adverts Which Falsely Claim Price Of Wind Energy Has Fallen By 50 Per Cent"
The cost of wind energy at market has fallen even more than this - but not because the production of wind plants got so cheap, but because wind energy is non reliable and of low quality for grid - it tends to destabilize it. For to have wind energy comparable with coal energy, it should be delivered with the same reliability - that means, all wind plants would need a battery backup and the energy and materials introduced into backup solutions should be also accounted into their EROI - which generally aren't. Without it the environmentalists are just comparing apples with oranges. As you may guess, the contribution of wind plants to fossil fuel savings is much lower than generally assumed - simply because their proponents ignore most of hidden energy inputs of this solution. Even after thirty years of pushing renewables at market we have NO SINGLE COMPLETE ANALYSIS accounting it.
TrollBane
5 / 5 (2) Dec 27, 2017
With better materials and design, new turbines might well last longer. Here's one look at smaller turbines. (unchecked numbers) https://www.popla...k-period

An analysis of larger turbines: https://www.saskw...-turbine
mackita
3.5 / 5 (4) Dec 27, 2017
@TrollBane: Show the numbers and you'll see. How much energy all these resources will consume?
gkam
1.8 / 5 (5) Dec 27, 2017
Okay, mack, and you do the same for a nuclear powerplant.
carbon_unit
5 / 5 (3) Dec 27, 2017
Okay, mack, and you do the same for a nuclear powerplant.
And while you're at it, look at the cost per unit of capacity to clean up a wind farm that is destroyed by a disaster vs the cost to clean up a nuke plant.
antialias_physorg
5 / 5 (1) Dec 28, 2017
Agreed. However, a modest amount of fossil fuels, nuclear and geothermal should be an acceptable contribution to the overall picture - 'til the fusion gorilla enters the room

There will be some gas powered plants to tide over small scale variability and for the rare, prolonged periods where renewables can't produce. That's perfectly fine.Biogas (or eventually hydrogen fuel cell stations) would be preferrable over fossil gas, though.

I'm in two minds about fusion*. On one hand it is a safe and relatively clean power source. On the other it would - due to the cost of such powerplants - put energy production back into the hands of subsidized monopolists. I'd rather see the current setup continued where solar/wind generators are affordable to set up on a communal (or even private) level.

(* on Earth. In space fusion will be a must as there's really no viable alternative for anything larger than a large satellite/tiny station.)
antialias_physorg
5 / 5 (4) Dec 28, 2017
Anybody have any number to show that 20 yrs of a turbines life produces more energy than it took to create, install, maintain and decommission it it?

Here's something even better: A meta-analysis of 50 papers on the subject

https://www.soest...En10.pdf

Summary: EROI of installed turbines is 19.8. EROI of future turbines is 25.2

Note that this only takes papers until 2010 into account. So if anything these numbers for wind turbines are at the very low end. There is a positive relationship between EROI and rotor diameter, and diameters have been steadily increasing.

(Note that the EROI of a coal powerplant is about 8.0, Nuclear is about 15.8, but with a very high variability as there are many unknowns for the decomissioning stage...so wind beats the conventional power systems by a pretty big margin.)
unrealone1
2.3 / 5 (6) Dec 28, 2017
Roughly 1 million turbines to run the USA and replace them every 20 years.
The motor of Toyota's Prius, for example, uses about a kilogram of rare earths. Offshore wind turbines can require hundreds of kilograms each. 300k?
How much waste is produced for every tonne of Rear Earth magnets made? That's the question?
https://www.techn...-crisis/
antialias_physorg
3.7 / 5 (3) Dec 28, 2017
To drive the point home a bit:
Coal: EROI = 8
Nuclear: EROI = 16
Wind: EROI = 20 - 25

Since wind has been dropping below coal/nuclear in cost in only the last two years this really puts into perspective how much of our taxes have gone (and are going) to subsidizing these old forms of energy generation (i.e. how much more you and I have - NEEDLESSLY - spent on electricity per kWh when we factor everything in).

I don't mind paying taxes. I DO mind paying taxes for stuff that have better and cheaper alternatives freely available.
WillieWard
2.3 / 5 (3) Dec 28, 2017
Coal: EROI = 8
Nuclear: EROI = 16
Wind: EROI = 20 - 25
Coal: EROI = 30
Nuclear: EROI = 75
Wind: EROI = 16(without batteries), 4(with batteries)
https://blogs-ima...gure.jpg
http://rameznaam....ydro.png
There is no factory 100% powered by sunshine&breeze producing windmills and solar panels.
"Nothing restricts the renewable energy but physics (energy density)."
Solar Electricity(PV): Invented 1883. Reliably powers zero industrial nations today.
Wind Electricity: Invented 1887. Reliably powers zero industrial nations today.
Nuclear Electricity: Invented 1951. Reliably supplies half the electricity in 5 industrialized nations today.
https://uploads.d...dcc2.jpg
https://pbs.twimg...A4Q1.jpg
gkam
2 / 5 (4) Dec 28, 2017
It's too late to save nukes now. We cannot afford them, and STILL do not have a way to safely store the nasty nuclear waste they produce.

Trying propaganda from the past will not help, either.

They are LOSERS.
mackita
2.3 / 5 (3) Dec 28, 2017
Why nuclear power will never supply the world's energy needs - there is not enough of uranium for everybody The only sustainable solution which I can recommend for everyone is: learn about overunity findings and cold fusion research. Each day we will delay its implementation it's not only wasted, but it destroys or future life environment for our children and most of all it increases the risk of nuclear confrontation (the wild fight for remaining raw source reserves). After all, we need to save oil reserves for plastic industry - we cannot afford to burn them all anyway.
Eikka
4.2 / 5 (5) Dec 28, 2017
Save the hate. I was a Senior Engineer in Technical Services


Save the lies George Kamburoff. You were never a licensed engineer, and it's illegal in California, where you live, to call yourself an engineer or hold such title for a profession if you aren't licensed. The proof is in the records, as this information is public. You're a charlatan.

People don't forget that you've been lying about all your credentials and making appeals to your own non-existing authority for years and years, and this too won't vanish from the internet. You've ruined your own reputation.
WillieWard
1 / 5 (3) Dec 28, 2017
...nuclear waste...
It emits less radiation than a bunch of bananas, has killed no one, is safely stored in dry casks, and all U.S. waste fits in a football field; meanwhile wind and solar produce 300x more waste(arsenide and other chemical carcinogens that never lose their toxicity with time) that are dumped directly into the environment.
https://www.youtu...Q_6fuGNI
"Used Nuclear Fuel - Part One"
https://www.youtu...vIzH2W6g
"Used Nuclear Fuel - Part Two"
https://www.youtu...dQQsxiq0
"Used Nuclear Fuel - Part Three"
https://www.youtu...ZMxf_kZg
1,000,000,000 solar panels coming soon and will be dumped directly into the environment.
https://pbs.twimg...qDuq.jpg
gkam
1 / 5 (3) Dec 28, 2017
Oh, my, Eikka.

Getting rudely personal is the sure sign of having lost the argument.
Steelwolf
5 / 5 (1) Dec 28, 2017
Themajor reasons for wind turbine replacements is the fact that after 20 years the bearing have taken a LOT of wear, the blade-shaft materials have been stressed and overstressed beyond safety levels due to increased and accellerating microcracking and the fact that it is now cheaper to replace with newer units han try to do repairs (MORE Repairs) on the older units.

Still one heck of a lot cheaper than Diesel Generators which are always breaking down in some fashion due to the much greater number of moving parts.

And nuclear waste, while the majority of it is low level such as the radiation suits or tools used, the radioactive materials themselves are DEADLY dangerous in their modern concentrated form and must be shielded to a very high degree.

People untrained in proper handling of nuclear materials are plain clueless as to the threat they actually are.
Eikka
4 / 5 (4) Dec 29, 2017
Getting rudely personal is the sure sign of having lost the argument.


What argument?

The only argument you've given is an argument-ad-hominem about your own expertise and superior authority, which is directly debunked by the lack of any real credentials on your part and your continuous lies which are proven as lies by publicly available information.

There's nothing rude about exposing a liar - it is the liar who is being rude by assuming others are too stupid to notice. You made the argument about you, so deal with it.

Eikka
3 / 5 (2) Dec 29, 2017
Still one heck of a lot cheaper than Diesel Generators which are always breaking down in some fashion due to the much greater number of moving parts.


Having been inside a wind turbine, there are a great number of moving parts. There's a whole big gearbox, hydraulic systems, cooling systems, heating systems, a multitude of bearings for the turbine and the nacelle. It's hardly any less complicated than a diesel engine.

A big powerplant diesel engine is actually quite simple, as its crankshaft is coupled directly to a generator and it just turns at a constant speed.

What actually breaks down are things like the hydraulics which turn the top of the turbine around, because they're under a lot of stress. The Danish-made turbine I had the opportunity to observe was blowing gaskets and o-rings and breaking the nacelle turning gears almost yearly because it wasn't designed well for the environment and suffered greatly from icing and temperature swings.

gkam
1 / 5 (3) Dec 29, 2017
Oh, boy, . . that proves it. Because Eikka says bearings and gaskets are used, the technology is no good.

I think I will send some incidents regarding coal and nuke plants and their designs. We can start with Fermi I, with which he is unaware, go through some grossly-expensive and worthless "clean coal" facilities, and wind up at Fukushima.

As far as myself, since I use my real name, something Eikka cannot do, folk can look me up.

I am real, Eikka and really was Senior Engineer in Technical Services for what was then the largest non-governmental electric and gas utility on Earth. Yes, I know it hurts your feelings and you have to take nasty shots at those us us with experience, but you are losing.

Losing.
Anonym683774
1 / 5 (4) Dec 29, 2017
They really should attempt to implement Tesla's wireless Electricity 1 it would lower costs by extremely reducing the amount of copper necessary & 2 in those remote locations everyone knows everyone so nobody would be able to tap into the power for free, but their meters could be set up to track the total current used in the surrounding area to help identify anyone trying to tap into the power without a meter to allow them to be charged, simply knowing Tesla didn't want to make energy free he simply wanted to reduce its cost and I really doubt he wanted to see the planet covered with power lines after seeing what that shit looked like after creating his Niagara Falls Power station he knew there was a better way and actively sought a way to do away with the wasting of all that copper. I have even read articles on ways the ground can act as a battery tapping into the planets own electrical fields which is how the old telegraph system functioned before they got actual batteries they had
Anonym683774
1 / 5 (2) Dec 29, 2017
they would use the earths natural electric fields to power the telegraph stations.
WillieWard
2.3 / 5 (3) Dec 29, 2017
Oh, boy, ...
As far as myself, since I use my real name...
I am real ... really was Senior Engineer in Technical Services for what was then the largest non-governmental electric and gas utility on Earth. Yes, I know it hurts your feelings and you have to take nasty shots at those us us with experience, but you are losing.

Losing.

"Who but george kamburoff takes george kamburoff seriously?
Nobody here.
Nobody out there, which is why he spends all his time here (wasting ours)."

antialias_physorg
4.4 / 5 (7) Dec 29, 2017
Erm..you are aware that to power anything you need a *moving* magnetic field

The Earth's magnetic field is not moving (relative to a stationary apparatus on the ground)

(If that didn't spell it out to you: Tesla knew a HELL of a lot more about electrical fields than you do, apparently)
Eikka
3 / 5 (2) Dec 30, 2017
The Earth's magnetic field is not moving (relative to a stationary apparatus on the ground)


It is moving with the solar wind, which induces currents into the ground - which were sometimes used to power telegraph equipment.

You bury a hunk of metal in the ground and draw a wire in a specific direction, and you get some small amount of power out of it.

https://en.wikipe..._current
antialias_physorg
5 / 5 (2) Dec 31, 2017
Try using that to power a telegraph station (not just at all, but reliably) as Anonym879203 proposed.

The notion is pretty ridiculous.

Eikka
4.3 / 5 (3) Jan 05, 2018
The notion is pretty ridiculous.


Not really. It was in fact used.

When an "earth battery" was constructed by sinking different metal plates, e.g. zinc and copper, into the ground, it was found that the battery would last significantly longer if it was oriented along the telluric currents and sometimes no observable corrosion would happen, as if the battery was being recharged.

In the Morse system, the two ends of the telegraph wire are grounded so that any station along the way connecting its battery to the wire would cause all the recieving relays in series along the wire to activate. These Morse relays would switch a low-voltage 1 - 1.5 V local battery as a mechanical amplifier to operate the actual buzzer or clicker mechanism, and the earth battery was used to maintain power to listen to the transmissions without the need to continuously replace batteries.

Anonym683774
5 / 5 (1) Jan 08, 2018
LOL I love the Comment Above by Eikka :-) I'm Glad at least 1 other has Actually Opened a Book in their Life.

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