How US power grid operators managed the solar eclipse

[gary]

Peter Fairley, in a 21 August 2017 article (https://spectrum.ieee.org/energywise/green-tech/solar/how-california-grid-operators-managed-the-eclipse)at the Institute of Electrical
and Electronics Engineers (IEEE) Spectrum magazine web site, reports on
how US power grid operators managed the drop in power during the
solar eclipse.





Article here :-
https://spectrum.ieee.org/energywise/green-tech/solar/how-california-grid-operators-managed-the-eclipse

[Wavytone]

what do you think happens at night ?

An eclipse is nothing in comparison...

[gary]

One might readily assume so, but from the perspective of grid operators,
an eclipse brings about a very large down and up swing in available power
over a relatively short period of time (i.e. a few hours).

So an eclipse provides a unique challenge distinct from cloudy days
or the day/night cycle.

For example, in 2015, Europe lost and regained about 17 gigawatts in
the morning of March 20th during the eclipse. That is a massive amount
of power - by comparison about half the power generation of Australia during
a peak period.

The Europeans were prepared and had planned for it.

But if they hadn't, it may have brought down the grid. A curious thing
for the Moon simply passing in front of the Sun. :thumbsup:

[fsr]

I'm pretty sure that any concern about this matter was only generated thanks to mass-media yellow press trying to invent catastrophe from thin air, or maybe just trying to give renewable energy a bad image. The numbers may seem large, but as mentioned, any day to night transition would be way worse than any solar eclipse, and yet, nothing explodes.
The eclipse is just a small moving spot where the sun is totally eclipsed, the rest of the area is dimmed. Doesn't seems like such a problematic issue for an interconnected power grid.

[gary]

Hi Fernando,

Thanks for the post.

On the contrary, the article was not generated by the mass-media in order
to create hysteria.

It's an article written by electrical engineers with a primary reader target
of other electrical engineers and was published on the Institute of
Electrical and Electronics Engineers (IEEE) web site.

The IEEE is the world's peak professional electrical engineering
body. Globally it has some 420,000+ members in 160 countries making
it the world's largest technical professional organization for the
advancement of technology.

It consists of dozens of "societies" ranging across the entire gamut of
electrical and electronic engineering including aerospace, communications,
computing, engineering materials, nuclear engineering, photonics, power
and energy, robotics, signal processing, transportation, biometrics ,
microelectronics and semiconductors, nanotechnology and so on.

It publishes hundreds of journals and magazines and every year
has jurisdiction over 1,800+ global conferences.

It also maintains hundreds of global standards. For example, consider the
up and coming 5G mobile telephone communications technology. That is
an IEEE standard. The way floating point arithmetic is performed in all
computers is an IEEE standard. There are dozens of IEEE standards
governing the design and testing of the electrical, electronic and computing
systems deployed within nuclear power plants. Standards for smart grids.
Standards for photovoltaic modules and power systems. Standards for
power grid designs and operation. Standards for semiconductor clean
rooms. And so on.

In the case of power generation and distribution, the IEEE membership
is responsible for it all. Electrical engineers designed every electrical
power source, both the old non-renewable and the very latest renewable.

The IEEE has its origins in 1894. It started with telegraphy, then a main
focus on AC power generation and distribution, with wired communication,
both telephony and telegraphy being a secondary focus. It started with
people like Edison, Tesla and Bell. Some of its highest awards are named in
their honour.

In the case of the power grid, to the man-in-the-street, they just know that
they flick a power point switch and the power is there.
But behind the scenes, the operation of a power grid requires
day-to-day and moment to moment oversight and management by
operators.

Power grids are complex things. In fact, they are some of the largest
and most complex engineered systems and the physics involved
in transferring power is non-linear. Voltage collapse can rapidly occur
throughout the entire network cascading from a small disruption somewhere.
In worse case scenarios, an entire grid can collapse within a fraction of
a second.

Power stations go on and off line. Coal and gas powered
stations require a continual mechanical feeding of fuel. Winds vary
from time to time at wind turbine locations. Clouds pass over solar
power plant arrays and urban rooftop deployments.

Some of these events the grid can be pre-programmed for or ridden out.

Some are exceptional and perhaps even unexpected, such as a power plant
failure or a storm bringing down power transmission lines.

In the case of the recent eclipse in the US and the one in Europe in 2015,
human intervention was required in the management of the grid otherwise
there was a very real chance that the grid might come down.

But both events were anticipated and planned for and where intervention
was required, it was done so successfully.

So the article is simply one group of engineers saying to other engineers,
"this is how we did it". And they did it calmly, coolly and rationally.
In other words, exactly how they are paid to do it. No hysteria, no
panic. But if they hadn't done it, then what the man in the street takes
for granted may have stopped working.

It also provides an interesting anecdote - interesting at least to engineers
or to people who just love to know how things work - as to the extent of
deployment of solar generation in the US and Europe at this point in
world history.

That a solar eclipse with its finite full and partial shadowing lasting
only a few hours can, in the case of Europe, see an 18 to 25GW
dip in the available power on the grid. That much power is no small
beans and it says a lot about the achievement of designing, constructing
and interconnecting the enormous amount of solar power generation
involved.

It also provides some feel for the enormous amount of energy dissipated
from the Sun. The world has an insatiable appetite for electrical power
and it is remarkable that so much of it can be grabbed out of thin air.

Anyway, I hope you and other readers found the article and this background
interesting. There are professionals working behind the scenes to keep
our technological world running.

Best Regards

Gary Kopff
IEEE Member 39 years

[fsr]

Thanks, the IEEE article is very good. It seems to me like there were extra measures taken to ensure everything runs smoothy, but at the same time, it's mentioned that the conditions they were expecting are "something CAISO had contended with on certain days in the past when moving cloud cover overlapped with sunrise or sunset".
Anyways, it's surprising to see that this needs intervention. The totality shadow had a 100 mile radius. Quite small compared with the rest of the grid.

But stuff like this circulated before the eclipse in mass media (in fact, this is the article that someone posted while i was watching the NASA live stream): https://www.bloomberg.com/news/articles/2017-07-14/a-solar-eclipse-could-wipe-out-9-000-megawatts-of-power-supplies
Quite pessimistic. That's the kind of articles i was referring to. Well, at least they didn't mentioned blackouts, but they do whatever they can to make it sound like solar is somehow "bad". They don't mention that solar is collecting energy that is just freely shining all over us, however. That certainly has some value.

[Wavytone]

Some of you need to recognise even reputable journals such as IEEE Spectrum sometimes publish FUD articles - the "peer reviewers" may miss the most basic of commonsense checks and a stupid article - FUD in this case - is published.

Engineers aren't stupid and as an EE who has a background in control systems and power distribution I can say this should never have got past the peer reviewers for the simple reason I pointed out - the disturbance caused by an eclipse is trivial compared to the day/night cycle.

"Cold fusion" is a notorious example.

[gary]

Thanks for the post.



But there is no FUD - "Fear, Uncertainty, Doubt" - in the article.
The author is simply quoting the network operators as to their plans
in handling the event on the day. :) If anything, the article is calming.



The fact that the coming of nightfall causes a total disruption in solar power
certainly isn't lost on anyone.

The point that the author, and in quoting them directly, the operators,
are making is that a solar eclipse nevertheless now requires
careful consideration and planning.

If we were to go back 20 years ago, with respect to the grid,
we would not have considered it.

California Independent System Operator (CAISO) oversees the operation of
California's power grid and electricity market. One of their guiding
principles is to operate the grid reliably and efficiently.

One would assume that when they planned for the solar eclipse months
before the event, they knew what they were doing. In a report dated
1 May 2017, they wrote (http://www.caiso.com/Documents/Briefing_SolarEclipse-ISOReport-May_2017.pdf):-



WECC refers to the Western Electricity Coordinating Council grid which
covers the west of the United States and Canada. A large area.

So given that the eclipse was a significant enough event to require
consideration, planning and intervention by the grid operators, reporting on it
by IEEE Spectrum was appropriate and would have easily passed peer review.

That May 1 2017 CAISO report here :-
http://www.caiso.com/Documents/Briefing_SolarEclipse-ISOReport-May_2017.pdf