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Comment: Re:How could they? (Score 1) 179

by Mike_EE_U_of_I (#48821191) Attached to: Marriot Back-Pedals On Wireless Blocking

At some point, someone said "ummm, guys, we can't legally do that" and was told to STFU.

I've been in meetings like that before. I suspect it was more along the lines of this.

Suit 1: So, we can block all the wifi hot-spots and make everyone pay us $10-$100 a day for access. Any downsides?

Suit 2: Yeah, it is illegal.

Suit 1: So, what happens if we are caught?

Suit 2: A fine, something like a million bucks tops.

Suit 1: LOL, and this thing could bring in five grand a day in revenue per hotel. No brainer, Approved!

IMHO, this is why the fine should have been much much bigger. I'd wager serious money that Marriott came out ahead on this. It has a taste to me of fining a bank robber 10% of what he stole and calling it a day.

Comment: Re:Are they really that scared? (Score 1) 461

by Mike_EE_U_of_I (#48539603) Attached to: Why Elon Musk's Batteries Frighten Electric Companies

Personal experience. My wife runs a solar energy web site and she routinely interviews people in the solar industry. That includes executives at electric utilities. I am the camera man. Since I am an electrical engineer, I always chat with the people before and after the on-camera interview.

The difference in attitudes towards solar PV before and after that report were nothing short of jaw-dropping. It was kind of amazing how patronizing many (most?) people in the utilities were towards solar. That report was like everyone in the industry had just watched a horror movie involving their own personal destruction. No one is dismissive or patronizing towards solar PV anymore.

BTW, possibly my favorite interview is this one: https://www.youtube.com/watch?...

Karl Rabago is a great pro-solar guy who is also been utility guy who has also been a regulator. That gives him an amazingly well rounded perspective since he is one of a very small number of people in the industry who has been on both sides of the table.

Comment: Re:Are they really that scared? (Score 5, Informative) 461

by Mike_EE_U_of_I (#48532069) Attached to: Why Elon Musk's Batteries Frighten Electric Companies

The Edison Electric institute is a trade group for electric utilities. They published this report in January of 2013.


That report changed the attitudes of a huge number of electric utility executives. Before this report, I would describe most electric utility executives as indifferent to solar PV. They viewed it as a marginal technology and that it would probably always be a bit-player. After that report, pretty much none of them feel this way. Many executives at electric utilities are terrified of solar and are spending significant amounts of money lobbying against it.

Comment: Re:No, no feasible storage, not even close (Score 1) 237

by Mike_EE_U_of_I (#48144897) Attached to: Can the Sun Realistically Power Datacenters?

I agree it is cheaper to buy it from the power company today. That said, we might be a bit closer than most people think. LCOE (Levelized Cost of Energy) of new solar PV is around 10 cents per KwH. Right now, energy storage is in the ballpark of 30 cents per KwH. Get one third of your power without storage and the rest has to cycle through storage, and you are looking at an average cost of around 30 cents per KwH. About the only place that would save money right now is Hawaii.

  Going forward, Solar PV's price has been falling by around 8% a year for decades and I don't see that trend stopping any time soon. Battery costs have been falling even faster, but let's use 8% for those as well. By 2020, we will be looking at 20 cents a kwh. By 2025, it should be down to 13 cents, and by 2030 about 8.5 cents. Remember, that's for a system with solar PV and storage to take you through the night.

  That's assuming no big tech breakthroughs, just the incremental 8% a year we have been doing.


Comment: Possible sequence (Score 3, Insightful) 171

by Mike_EE_U_of_I (#48074137) Attached to: Apple Sapphire Glass Supplier GT Advanced Files For Bankruptcy

I don't know that this is what happened, but it seems likely.

1) Apple wants to use sapphire for main glass in Iphone.

2) Apple signs contract with GTAT to supply the sapphire, including a pile of money to build sapphire production facilities.

3) Apple pushes all risk onto GTAT. IOW, if Apple decides not to use the sapphire for the displays, GTAT has to repay the pile of money from step 2.

4) Apple does not use sapphire. GTAT can't repay money because they already spent it building sapphire production lines which no have no demand.

5) GTAT declares bankruptcy.

Comment: Re:Yes, we know that. (Score 1) 245

by Mike_EE_U_of_I (#47839873) Attached to: Power Grids: The Huge Battery Market You Never Knew Existed

The reason it is difficult to handle the load swings is that coal and nuclear plants can not be quickly turned off and on. For example, it can take a full day or two for a coal power plant to go from cold start to full power output. We do have some power plants that can react quickly, natural gas can react in a few minutes with the newest plants to an hour with the older ones. Hydro is very fast and can be switched off and on in seconds.

  So take a typical grid that is getting half it's power from coal, maybe 10% from nuclear, and the rest from natural gas and hydro. Now do what Germany did and put in enough solar PV that 5% of the total energy of the year is coming from solar PV. As the previous article showed, the instantaneous peak that results from this is as high as 50% of the total demand. In Germany's case, when that happens, all the gas and hydro plants are off and all their power is coming from coal, nuclear, and solar. And there is the breaking point. If solar increases any more in Germany, when solar is peaking, they either have to start rejecting some of the solar power, the coal power, or the nuclear. The solar can not be rejected under current German law, which leaves only coal or nuclear. And those boys really can't turn off their plants very well. The result is that they push the spot price down to encourage anyone who can respond to the spot market to take power.

  Germany has already experienced negative electricity prices in the spot market because of this problem.

  Now imagine Germany doubles the amount of solar PV they have. This would result in them getting around 10% of their total electrical energy from solar PV. The instantaneous peaks would be as high as 100% of total demand. What is supposed to happen then? The obvious thing to do is to simply cap solar PV to an instantaneous peak of around 50% of total demand. That happens infrequently enough that Germany could still probably get 9.5% of their total energy from solar PV. That only would reject about 5% of the power the solar panels could have collected. That's reasonable technically, but illegal under current German law.

  If you look at this paper, http://papers.ssrn.com/sol3/pa...

  The authors introduce the concept of system-LCOE. LCOE is levelized Cost Of Energy. It is a common utility term. The idea is to sum up every single cost to produce electricity and reduce it to a single number. Historically, LCOE ignores any issues with integrating with the grid. System LCOE is meant to try to incorporate both LCOE and grid integration issues. If you look at their graph on page 19, you can see how the cost of integrating solar PV increases quite dramatically as the share of energy coming from solar increases. If their graph is correct, Germany is paying in the ballpark of 15% extra to integrate into the grid.

Comment: Re:Yes, we know that. (Score 1) 245

by Mike_EE_U_of_I (#47818931) Attached to: Power Grids: The Huge Battery Market You Never Knew Existed

Once Solar PV penetration gets to the point where about 5% of all electricity is coming from solar PV..

Uhm. You realize you're talking almost a (not even taking into account rising consumption) 20-fold increase right?

Germany is already past that.


In 2013, Germany got 5.3% of their total electrical energy from Solar PV.

Comment: Re:Yes, we know that. (Score 1) 245

by Mike_EE_U_of_I (#47818905) Attached to: Power Grids: The Huge Battery Market You Never Knew Existed

That means the instantaneous peaks will be in the ballpark of 50% of grid energy coming from solar.

Is that EE is your username a mere unused decoration or an utter lie? Who outside of bad science fiction is suggesting 50% of grid energy coming from solar?


Germany hit over 50% of their instantaneous electrical power coming from solar on June 9th of this year.

  I think you are confusing instantaneous and total power.

Comment: Re:Yes, we know that. (Score 3) 245

by Mike_EE_U_of_I (#47802233) Attached to: Power Grids: The Huge Battery Market You Never Knew Existed

Battery storage for bulk power has been talked up for years. Mostly by the wind industry. With solar power, you get peak power and peak air conditioning load around the same time.

I agree that has been historically true, but that's changing fast. Once Solar PV penetration gets to the point where about 5% of all the electricity is coming from solar PV, it starts to get really expensive to handle the load swings. To be clear, I mean 5% of total electrical demand for the year. That means the instantaneous peaks will be in the ballpark of 50% of grid energy coming from solar.

  Most countries are very far from this point, but Germany and Italy are there today. Both countries have dramatically slowed their adoption of solar PV, mostly because of grid integration issues. All of those issues would be solved with cheap storage.

Comment: Re:Just the cost of doing business. (Score 5, Insightful) 311

by Mike_EE_U_of_I (#46908399) Attached to: Steve Jobs Defied Convention, and Perhaps the Law

Seriously, where do they get off saying it's rare for big companies to do illegal shit? Name me one that *doesn't* at least walk really close to that line.

I've consulted in big companies for quite a while. My experience has been that most of time, most people are trying to obey all the laws. That said, yes, "the line" does get crossed. In all the cases I've personally seen, "the line" was crossed either because of ignorance or for precisely the reason you state (the fine is lower than the expected profit).

And that's why this case is astonishing. Steve Jobs went so far over the line, he might have wound up in jail. That's something I've not seen. You know why no banker went to jail? I've seen this shit in meetings. Someone proposes something that is illegal. The discussion then focuses on costs and profits. It then moves to plausible deniability and the chance of going to jail. If the conclusion is that there is the slightest chance someone will go to jail, that's it. That idea is dead dead dead.

  Steve Jobs, like the Honey Badger, didn't care. He left a trail, IN WRITING, that could have put him in jail.

Insanely illegal.

Comment: Re:As others said, no .... but .... (Score 1) 734

The key here is the question specifically about *solar* power. When you look at the sum total amount of energy we consume, I think you'll find that you'd have to blanket a pretty significant portion of the usable surface of the earth with panels to provide all of it, if you went strictly solar.

Yes you would.

Fortunately, we already blanket a pretty significant portion of the earth with buildings, roads and parking lots. Put solar on all the buildings and cover the parking lots and you are well over half of the way there.

Here is the NREL report on this subject.


NREL states we would need 00.4% of all the land in the USA to go 100% solar electric. The report uses existing PV efficiencies. By the time we could possibly be near something like 100%, efficiencies will be higher and that land requirement will be down to something like 00.35% or lower.

Comment: Re:Safety (Score 2) 937

by Mike_EE_U_of_I (#45909067) Attached to: Who Is Liable When a Self-Driving Car Crashes?

And if *all* the cars on the road aren't autonomous, then the autonomous ones are mostly a traffic hazard with no clear liability.

The google self-driving car has already shown itself to be insanely good at avoiding crazy human drivers. Even going as far as swerving out of the way of human drivers trying to ram it. The only way autonomous cars will be a traffic hazard to human drivers is if the production cars take a HUGE step down from the existing prototypes. That's just not going to happen.

    I little bit of that is here http://www.technologyreview.com/news/520746/data-shows-googles-robot-cars-are-smoother-safer-drivers-than-you-or-i/

"Well, if you can't believe what you read in a comic book, what *can* you believe?!" -- Bullwinkle J. Moose