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Comment: Re:"Dance" = rolling blackouts (Score 1) 436

by geoskd (#47693503) Attached to: Is Storage Necessary For Renewable Energy?

The reason you need so much available is so that statistically speaking, you will never have a time when your supply is insufficient to meet demand. If your supply fluctuates between 20% and 100% of supply, then 100% needs to be 5x as much as demand to account for it. With renewables, the fluctuation can be anywhere from 5%-6% to 100%, meaning you would need at least 20x the *peak* demand to match potential minimum supply. In reality, you would need more than that as a margin for error. The more sane solution is to buffer a significant amount of energy and store it somewhere so that you could drop that supply from 20x+ to less than 3x. The larger the energy storage, the lower the average supply you can get away with. With conventional power, the supply ranges from around 80% to 100% available, so the system only needs about 50% excess capacity to meet demand without intermediate storage.

Comment: Re:"Dance" = rolling blackouts (Score 1) 436

by geoskd (#47691445) Attached to: Is Storage Necessary For Renewable Energy?

Your fridge can stand to shut down for five minutes to ride out a sudden but brief peak in demand. Those do happen. The 'Corrie Break' is a very well-known example, occuring predictably during the mid-episode break of Coronation Street in the UK - it's caused by millions of people simutainously going to put the kettle on.

These short term peaks are not the problem when it comes to renewable power generation. Those short peaks a (and troughs) are a problem that all power generation must face (and already deals with reasonably well). The problem with renwables is longer term generation across hours and days. You cant simply postpone running the pump for the water tower for two days because the weather forecast calls for cloudy and 0 wind for the next two days. The reality is that there is no amount of jiggering with the demand that will buy you that kind of time, and using only renewables without intermediate storage cannot provide reliable enough power supply across these larger time scales. A very large part of the cost of power generation is the cost of maintaining facilities, whether they are being used or not, so keeping a bunch of backup generation available for no-wind times, will only massively increase the already high cost of renewables. Ultimately the only way most renewables work is with lots of intermediate power storage to maintain the supply during low production periods.

Comment: Re:"Dance" = rolling blackouts (Score 1) 436

by geoskd (#47691407) Attached to: Is Storage Necessary For Renewable Energy?

Does that happen every time a coal or gas or nuclear plant has to perform an emergency shut down due to a fault? No? Why is that? Could it be that they keep some capacity in reserve? So why can't you simply build more renewable energy than you need most of the time, to cover those occasions when there is little wind?

Because without intermediate storage, the excess capacity that would have to be kept would be at least an order of magnitude greater than the "normal" fluctuation in the renewable supply. That "normal" fluctuation is already huge, so the excess capacity would have to dwarf the demand. Back of the napkins estimates would be around two orders of magnitude greater power production on average than demand on average. Renewables cant meet current demand, how are you going to achieve 100x that amount? Even if you could get it down to 10x (An amount far lower than I would be willing to bet on), that would still be outside the realm of feasibility, and even if it were feasible would be expensive enough to be impractical compared to large scale intermediate power storage...

Comment: Re:"Dance" = rolling blackouts (Score 1) 436

by geoskd (#47691369) Attached to: Is Storage Necessary For Renewable Energy?

I think you missed the point of the article. Demand is far easier to manipulate.

Demand is only easy to manipulate on short time scales. The longer the scale, the harder to manipulate. On scales of anything above an hour or so, it is impossible to regulate any better than we already are without large scale storage. Individuals and organizations are not going to tolerate waiting two days to activate device xyz, just because the northern hemisphere is experiencing a cloudy stagnant week with no wind. that means large scale non-renewable power generation facilities which cost a damn fortune to maintain, whether you're using them or not. The fact of the matter is that renewable sources are not sufficient for baseline power production. There is no amount of jiggering with the power grid, nor incentives that are going to affect that enough to matter, because fluctuations in power demand happen on timescales of hours, and fluctuations in renewable supply happen on timescales of days. The only way to get the two to jibe is to use intermediate storage capable of smoothing the fluctuations across the longest gaps, which means storage capable of meeting demand across days with no power input at all. That is not at all a trivial amount of storage, and again, no amount of playing with the demand can close a gap of days.

Comment: Re:Expert?? (Score 3, Insightful) 436

by geoskd (#47691179) Attached to: Is Storage Necessary For Renewable Energy?

No, that's not what he is proposing. He is suggesting that the demand can be controlled to some extent with smart appliances, some assistance from industry and small scale storage.

On that score, he is just plain wrong. The demand side predictability is not the real problem. The problem is that with renewables, there are large periods (hours and days in length) when the supply does not meet the demand. No amount of jiggering with appliances is going to close that gap. Significantly oversizing the supply, or significant storage is the only way to solve the fundamental problem. This guy is assuming that the shortfalls in the supply side are on the order of minutes. The reality is that the shortfall is on the order of days. You cant put off running a refrigerator for two days because there is a two day period of low wind in your offshore wind farms, no matter how far in advance you predict the shortage...

Comment: Re:Expert?? (Score 3, Insightful) 436

by geoskd (#47690693) Attached to: Is Storage Necessary For Renewable Energy?

Does he? His only claim here is that both supply and demand can be predicted, and that these can be choreographed to optimize utilization. He mentions that current power generation technologies are not available 100% of the time and proposes that the predictable variability of renewable power would be functionally no different. Nowhere does his proposal require loss-less, instantaneous, unlimited transmission of power.

The problem with this moron is two fold. First, he is not an electrical engineer, but a physicist which gives him absolutely zero qualification as an electrical grid engineer. The second and more direct problem with his hypothesis is that the system he describes is a classical control problem. In a normal control configuration, you have a demand for resources which you use your control of the supply to meet. It is a largely closed loop operation. With this guys setup, you have your usual, largely, uncontrollable demand, but now you are meeting that demand with uncontrollable supply. At best case, you have some limited ability to reduce the supply, but with renewable, there is a fixed upper limit to your supply, which could at any given moment amount to zero, or close to it. With base-load supply (such as coal or nuclear), there is a minimum supply you can count on, which is your fall back, and is 100% (or close to it) reliable. With renewable, you have only half of the controllability (no ability to increase production) which means you have to size the grid so that the odds of not producing enough power at any given moment is many standard deviations below capacity (probably at least 5 for reasonable reliability). That means making a power grid that produces several orders of magnitude more power than needed , on average, just so that the low point in the production scale is still above the high point in the demand scale. Its an idiotic solution from an engineering perspective, and is a perfect example of why scientists should not try to venture opinions outside their expertise.

Comment: Re:suitable for home use? (Score 1) 178

by geoskd (#47684329) Attached to: Hemp Fibers Make Better Supercapacitors Than Graphene

so I'm interested why you think it is so wrong?

The problem with it is longevity and maintenance. The industry is still using lead acid batteries for the same reason that it took 20 years for automakers to get around to having reasonable built in stereo systems. The manufacturers have a perception that what they have is good enough when it really isn't.

lead acid batteries under normal loading will only last about 8 years or so, with constant loss of performance during the entire period of their use. The solar companies started off using them because they concluded that it was the only technology available at that time that had the power density necessary to handle the household load. They were essentially correct, although NiCD and LiPO could both handle it, they offered no advantages over Lead Acid and cost far more. Ultra Caps have been available for about 5 years (and the costs have been steadily decreasing). The reason they are not widely adopted for Solar panel use is because they use a different charging methodology, and so can never be swapped in for lead acid batteries directly. Ultracaps have the advantage that they will outlast the structure, and are 100% maintenance free. This puts their long term (30+ years) cost far below lead acid even today. The cost of switching later is not trivial because that $1000 battery charging and monitoring equipment will have to be completely replaced when going to ultra caps, so it is purely wasted money. As you also noted, the Inverter is a completely different design between the two storage methods, so you can add the cost of a new inverter to the mix as well. So in the very short term (less than 10 years), lead acid is cheaper, and if the installation is not expected to last longer than that, then go for it. For the longer term, the cost of the batteries become non-trivial compared to the cost of ultra caps, and the cost to replace the control electronics makes it so that lead acid installation is a dead looser no matter when you switch over.

At the end of the day, it is why I strongly recommend waiting a few years while the solar industry catches up with the times and creates / markets the control electronics necessary to work with ultra caps, and for the price of ultra caps to come down further. In the long run, waiting 5 years will likely save you more than the 5 years worth of electricity...

Comment: Re:suitable for home use? (Score 1) 178

by geoskd (#47682431) Attached to: Hemp Fibers Make Better Supercapacitors Than Graphene

Care to pick apart the rest of his post point by point,

I took serious exception with the entire post, although I had only limited time to respond. In complete: Lead Acid is entirely the wrong technology for home solar installation, in spite of it being the relatively cheapest. The root reason is total energy density. Even though a home system does not have the space or weight limitations that a mobile system requires, lead acid has such a low energy density compared to virtually all modern option that it is not really suitable for any application except car starter batteries (where power density is paramount). The guy is clearly an "early adopter" who is trying to sound like he knows more than he does, and giving bad advice to boot. When he claims that ultra caps are unavailable at any price: he is dead wrong. And there is no battery system in the world for a solar installation that will function as well as ultra caps, even at current prices because of the virtually limitless charge discharge cycles of ultracaps vs chemical batteries. The best advice I can give to anyone, is if you are really dead set on getting solar right now, spring for the ultracap storage, because it will be significantly cheaper in the long run. A better bet still would be to wait 5-10 years and let the researchers do their stuff, as both chemical battery, and more importantly ultra cap storage is still improving at double digit rates in all metrics.

In summary, the guys confusion of power vs energy density, along with other shortcomings in his post told me that he had no engineering knowledge whatsoever, and at best was a "power user" / early adopter who was just regurgitating the same crap he read on some blog somewhere. The most dangerous misinformation is the crap that contains half truths, or lies by omission like this one. To people who don't know the difference, this guy sounds like an expert, and those people will repeat anything they hear unless there is an immediate and clear voice to call out the BS.

Comment: Re:suitable for home use? (Score 3, Informative) 178

by geoskd (#47674867) Attached to: Hemp Fibers Make Better Supercapacitors Than Graphene

The power density is really nowhere close to a battery. Supercaps make sense for things where you actually need really massive charge and/or discharge spikes, over very short times.

That is the definition of power density. You're thinking energy density. The fact that you would get the two confused casts aspersions on your knowledge in the field.

It should also be noted that almost all types of batteries have leakage current which renders them unsuitable for long term energy storage. Most super caps have a higher than normal leakage current due to the lower operating resistance of the devices (the same trait which allows them very high power density).

Comment: Re:Jezebel? (Score 1) 299

by geoskd (#47670791) Attached to: Writer: Internet Comments Belong On Personal Blogs, Not News Sites

Interesting idea about how the victims are to blame. I spose it's pragmatic advice. Still kind of comes off as douchey. I disagree. I think people, bullies especially, but even dickhead assholes like yourself need to learn manners. Shoving someone and calling someone a name is unacceptable in the real world. That's assault. And yet that type of shit is perfectly acceptable in elementary school. Why is that?

I didn't say the victims are to blame. What I did say is that we should consider alternatives such as "hardening" the victims against these attacks.

the analogy I will use is in public networks. Nobody claims that the guys attacking computer systems remotely are good guys, or that they should be tolerated, but not one sane security professional would fail to recommend hardening the victims against the attacks.

What I am saying is that we may or may not be able to change human behavior as far as bullying is concerned, but why not also try to help improve the social functioning of the victims as well.

I was one of those that got bullied pretty harshly in school. Beat up more than once, stuffed in small containers, had my stuff continually stolen and destroyed. Finally, one day in high school, I sat down and began an exercise in figuring out why I was bullied, and how I could make it stop. Maybe I'm smarter than most, but I finally figured out that it was largely my own behavior that attracted the bullies, and that the things within my own control could be altered to reduce and even prevent the bullying. A few examples: Until that point, I did not pay much attention to my personal appearance or hygiene. I don't think I smelled funny, but who knows, so I undertook a program to clean myself up and improve my wardrobe. In retrospect, I can say I was also very much of an attention whore. I would butt into just about any conversation just to hear myself talk, and so I undertook to exercise self control, and keep my mouth shut for the most part. I would help, when help was asked for, but I would not go out of my way to butt in.

One of the key pivoting points, was deliberately picking a fight with a bully. Once I had decided it needed to be done, I prepared myself for the fight. The key was: I expected to loose, but I didn't have to win the fight to win the war, all I had to do was walk away. I waited until I was being picked on again, and when the tormentor tried to walk away, I started shouting anything and everything I could to insult the guy. I finally hit a chord, and the guy turned around and belted me (bloodied me pretty good too). I got a few hits in, but by no account did I win. My victory came in that I walked away from the fight (we had to be broken up, as I knew we would eventually be). All I had to do was be seen fighting, and not to cave in. After that, I was not tormented anymore. I wasn't accepted into the group by any means, but at least I was left alone.

At the end of the day, I had to work pretty hard to overcome the bullying, because I didn't start to transform myself until very late in high school, but by the time I reached college, I was ready to begin with a complete understanding, and can say I was fairly popular in college, even with the same types of people who used to beat me up. If someone had intervened with me at a younger age and offered to help me get the bullies to leave me alone, I would have jumped at the opportunity. As an adult with the benefit of hindsight, I now understand that bullies are attracted to attacking th weak. Its part of how children establish the pecking order. Disrupting that goes against millions of years of evolution, and I expect you will not be able to remove it from our psyche without destroying all ambition (and possibly annihilating the human race. But those that are bullied have a powerful motivation to make it stop, and lack only a complete enough world view to know how, so lets help them.

Comment: Re:Jezebel? (Score 0) 299

by geoskd (#47667545) Attached to: Writer: Internet Comments Belong On Personal Blogs, Not News Sites

Bullies may not hate their victims per-se, but that doesn't really matter. They hurt other people for whatever reason, hate or amusement it doesn't really matter.

I seem to remember a nursery rhyme when I was growing up involving sticks and names and stuff. The point is that bullies only have as much power as their victims give them. The more they let on they have been hurt, the more the bullies hold sway over them. Like it or not, anti-bullying laws don't make the world a better place, they make the victims even less able to cope.

Put another way, when I was growing up, the victims of the bullies were pitied to an extent, but there were some who everyone just thought they had it coming. Those people were the ones who were so socially awkward that no-one had any empathy for them. The bullies were merciless with them. The solution to the problem isnt to make anit-bullying laws, its to reach out to those victims and help them to understand what makes them victims and how they can help themselves.

Much as people didn't feel a whole lot of empathy for these victims, when one of them stood up and fought back against a bully, popular opinion was with them, and everyone loved to cheer for an under-dog. What you will get with the current no-bullying policy, is zero social feedback to help these social outcasts to address the fundamental problems that cause them to be outcasts in the first place. They will remain socially isolated, and the problem will get worse, not better: Unless you want to start legislating whom kids can be friends with, and who they *must* be friends with...

Comment: Re:And yet (Score 1) 268

by geoskd (#47636939) Attached to: Judge Rejects $324.5 Million Settlement For Tech Workers, Argues For More

The problem in USA is not that Google and Apple had agreements not to hire from each other, it's that there are so few employers at all, and that's a problem of business costs being too high thanks to government rules, taxes, regulations, litigation costs, inflation etc.

No, the problem is the free market economy. Economists will tell you that the proper functioning of free markets requires several things. First, It can exist only in the presence of proper supply and demand. This requirement has a prerequisite: Scarcity. without scarcity, Supply and demand cannot work, and the free market economy adjusts to create artificial scarcity.

This problem is compounded in the labor market, where disenfranchised individuals go on to have very high costs for society. The markets approach to these (obsolete) people is to simply discard them, but in sufficient quantities these people can and will destroy society through political action, or in extreme cases, military action.

Both of these problems are compounded by technology which allows the general elimination of scarcity, especially in the labor market. This is having the effect of eroding one of the fundamental requirements of capitalism. In the 1930s, it took a radical social agenda to rip large amounts of capital away from the capitalists and basically give it to the bottom 10% to restore a temporary stability to the markets. Welfare, medicare and social security are all socialist concepts, and yet have been one of the only long term solutions to the problems listed above.

The problem with socialist programs is that, like anarchy, they cant truly exist outside of specific government protections because they require a power vacuum, and as soon as that exists, it is filled by the first people to show up (the last people you want in power).

Comment: Re:Not this again. (Score 1) 637

by geoskd (#47619319) Attached to: Ask Slashdot: "Real" Computer Scientists vs. Modern Curriculum?

That mattered briefly during the mobile revolution but was obsoleted after the second or third release. It's a neat skill, but like yodeling, doesn't really matter any more.

Wrong, very wrong, and terribly wrong. On any platform, memory equals money, storage equals money, and cpu cycles equals money. You might scoff and poke fun at the guy who says memory management matters, the extra ram only costs $0.10. The fact is that when you intend to sell 10M units, that $0.10 amounts to a millions dollars. If I told my employer that I saved them 3 weeks of my time by writing shitty code, but they would have to pay an extra $0.10 unit cost, I wouldn't last longer than it took my boss to finish spitting out the tyrade of expletives that I would have coming. If you're only selling 10,000 units, then the devs time is more valuable than performance, but anything above that number, and resource management matters big time. Web programmers get away with lousy code on a more regular basis, because they can offload much of the cost of processing on their customers. Even there they have to be somewhat careful because if the thing uses too much of the system resources, they loose a customer because of it...

I've seen companies dedicate an engineer to figuring out how to remove a $0.01 capacitor from a design because the savings annually amounted to close to 7 figures in unit cost... That's the guy that makes 250k/year and that is why he is earning it. Simply put, you're only worth as much to your employer as the difference to their bottom line because you're there. If they can replace you with an uneducated guy from Elbonia without hurting their bottom line, they're going to do it. If you want to make the real money, you have to know what the hell you're doing.

Comment: Re:Beards and suspenders. (Score 1) 637

by geoskd (#47618671) Attached to: Ask Slashdot: "Real" Computer Scientists vs. Modern Curriculum?

None of these or any other internal arcana of c have anything to do with designing algorithms or programming computers.

I defy you to write a compiler or kernel without such knowledge. Without that compiler you're not a programmer, youre a technical writer with aspirations. Without the kernel, you dont have a computer, you have a paperweight.

High level programmers can be replaced a dime a dozen because of languages like java. Low level programmers are sought after because they understand the arcane.

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