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Comment: Re:Nobody home (Score 2) 184

by geoskd (#47958503) Attached to: Secret Service Critics Pounce After White House Breach

wasn't there something a while ago about someone getting hammered for firing a .22 at the white house (think two inch thick laminated glass) while the president was abroad, yet he still got it for attempted assassination?

It was the motivation and intended outcome that mattered in that case. He shot at the White House with every reason to believe that the president was there, and no reason to believe that his bullet wouldn't penetrate the building and hit someone. He was guilty of attempted assassination. Just because he was ignorant doesn't mean he wasn't malicious.

Comment: Re:A solution in search of a problem... (Score 1) 326

by geoskd (#47918327) Attached to: Technological Solution For Texting While Driving Struggles For Traction

Traffic lights and crosswalks are certainly not mainly for the convenience of drivers, but are still very much necessary to save the lives of the few people that may have to walk into traffic

The same argument was made in favor of the reduction in speed limits. You might be right, you might not be...Show me the numbers...

Comment: Re:A solution in search of a problem... (Score 2) 326

by geoskd (#47901827) Attached to: Technological Solution For Texting While Driving Struggles For Traction

many studies have shown that when a car hits a pedestrian at 40mph the fatality rate is ten times greater than 30MPH. and in a school zone, there are a lot of kids around... we should be more vigilant about revoking drivers licenses.

How often do kids end up in a street around a school? Even during student arrivals and departures?

The reality is that it just isn't that often.

The hidden cost of speed limits is monumental: There are more than 100 million people driving to work in the US alone. The average commute is 25 minutes. If we slowed the speed limits by 10 MPH, that would increase the commute by a little less than 20%, so about 4 minutes per driver per day. That works out about 6.6 Million hours per day, or just over 1.4 billion hours per year. At an average US wage of over $20 / hour, The lost productivity is around 28 billion dollars per year.

Back in the 70's, the conservationists claimed we would get 5% or better improvement in fuel economy by switching to 55 MPH instead of 65. Turned out to be less than 1% improvement. That amounts to a saving of about 1.5 Billion Gallons of gas, or $6 Billion USD. So we spent 28 Billion to save 6 Billion.

OK, so we assume the rest is in lives saved. The NTSB has concluded that the reduced speed limits from 65 to 55 saved around 4000 lives annually, with reductions in speed limits from 45 to 35 saving less than 500 lives per year. Even all told, an across the board reduction in speed limits by 10 MPH would only save 5500 lives. That amounts to a cost to the economy of $4 Million USD per year per life saved. To put that in perspective, Mamograms are estimated to cost less than $50,000 per year per life saved.

So what about the school zones? how many Children are killed in these zones? The truth is that no one even keeps statistics that have any meaning because it happens so infrequently. Thats not to say that kids die from it infrequently, thats saying that kids are very rarely even hit in these zones. Its rare enough that we don't even really have a big enough sample size to be statistically useful.

The statistical truth at the end of the day is that our current speed limits cost our economy far more than they save. The Germans did what Germans do: They did the math. They concluded that on open highway speed limits would cost their economy more than they cared to pay, so they did away with them where they were not needed.

Comment: Re:In other news... (Score 2, Insightful) 216

People would lost their minds here if electricity prices tripled.

Thats the difference between the US and Germany. People in Germany have *chosen* to pay more for electricity and gas. They did so because they know that their money is buying better living conditions for everyone. Thats is why they have such high taxes. Funny but the typical standard of living in Germany is much better than the US in spite of the high taxes. In the US, its the exact opposite. Everyone wants theirs and Fuck everyone else. In the end everyone in the US suffers except the dwindling few who can hold on to upper middle class or better.

Comment: Re:In other news... (Score 3, Informative) 216

US starts buying more nuclear power from Canada, quickly pulling a Germany. In 5 years, subsidies much like those in Germany will then be gutted, and there will be a mass rush to build new coal and NG power plants until reactors can be refurbished or built anew.

Almost: Germany has been in a mad rush for quite a while to build solar and wind power production. The whole country is dotted with thousands of wind turbines, and a massive percentage of the country have solar panels to reduce their power demands from the grid. In short, Germany has been preparing for a while to reduce their reliance on fossil fuels, and was consequently in a position to abandon nuclear power instead. At their current build rate, in 10 years, they will only need 50% of the fossil fuels they use today, even with the nuclear plants shut down

The key to their success is that, for Germans, the overriding goal is environmental protection. Its a national obsession (Probably owing to complete lack of available land, and limited fossil fuels). Like Japan, one bad nuclear accident is guaranteed to affect a massive percentage of the population, fossil fuels leaves them too reliant on foreign powers. It means that Germany's only real option is renewable energy sources, and they have the political will and industrial might to make it happen.

Unlike American politics, the anti-environment sociopaths don't last long in German politics.

Comment: Re:"Dance" = rolling blackouts (Score 1) 442

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) 442

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) 442

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) 442

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) 442

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) 442

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).

Nothing is more admirable than the fortitude with which millionaires tolerate the disadvantages of their wealth. -- Nero Wolfe

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