tag:blogger.com,1999:blog-1592992209402300549.post1547081387358882692..comments2024-03-28T08:06:43.198-04:00Comments on The Silicon Graybeard: Techy Tuesday - RuminationsSiGraybeardhttp://www.blogger.com/profile/00280583031339062059noreply@blogger.comBlogger10125tag:blogger.com,1999:blog-1592992209402300549.post-15303176134254229912015-12-17T17:20:18.210-05:002015-12-17T17:20:18.210-05:00Solar or PV panels is a big disappointment. I got...Solar or PV panels is a big disappointment. I got my first solar cell sometime in the mid 50's and have been hooked on solar power ever since. But the one thing that has been true over these last 60 years is that the next breakthrough was just around the corner. Prices would drop and efficiency would improve. Well the prices ARE modestly lower and efficiency is modestly higher but in general the promises of dramatically better performance at dramatically lower prices just never happened and I'm guessing unless the laws of physics change or the laws of economics get turned upside down there will never be a dramatic breakthrough in PV. <br />Having said that I want to quickly add that there is a dramatic monetary breakthrough in PV. It is the government subsidy. If you want to become a multi-millionaire or maybe even a billionaire start a PV company and buy a congressman or two and they will make sure you get millions in subsidies.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-26850696479059808572015-12-13T16:36:31.769-05:002015-12-13T16:36:31.769-05:00Sorry - meant to tell you I have that report, then...Sorry - meant to tell you I have that report, then forgot to reply. <br /><br />I know that, as a group, we tend to have a "two is one, one is none" or double redundancy mindset. I think that in the wake of an EMP, there will be an odd mixture of things that work and things that don't. It's not going to "fry everything". Planes will not fall out of the sky - for several reasons. In tests I've seen, some cars get their ignition upset and stall, but they start again when the key is turned. And who isn't going to turn the key as a reflex? <br /><br />The only big problem is going to be the power grid and phone systems are going away, and I don't mean to understate that. That's very, very bad. That alone is enough to put us into the 18th century. <br /> <br />I just view EMP as another manageable problem. It's just an Electromagnetic Field thing. Pickup area is the single most important thing. I think VHF/UHF ham radios or FRS radios will be just fine and will help with communication. Bandpass filters are extremely effective protection. <br /><br />If you haven't seen it, you may find <a href="http://www.globalsecurity.org/wmd/library/report/1988/CM2.htm" rel="nofollow">Electromagnetic Pulse-From Chaos To A Manageable Solution</a> rather interesting. It's from a Marine Corps study in 1988. <br /><br /><br /><br />SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-79220091206547216592015-12-13T14:11:27.029-05:002015-12-13T14:11:27.029-05:00I would say, "not exactly". Diodes are ...I would say, "not exactly". Diodes are used as surge suppressors for lightning all the time, and are used to clamp the surge at that forward voltage. Think how zener diodes regulate. They're plenty fast enough for an EMP in a surface mount device (lower inductance than leaded part), although lightning is lower in frequency than EMP. Lightning strokes have energy into the mid HF range (2 to 30 MHz), while EMP is pretty much below 300 MHz. <br /><br />A surge is not the same as an applied DC voltage and you shouldn't think of surge suppression diodes that way. They're rated for an energy in Joules that they can clamp without breaking down, and are typically in shunt. Since heating is one of the effects that damages them, that's why I think junction size matters. <br /><br />This is way too deep a subject to get into here, but try searching for <a href="https://www.bing.com/search?q=transient+protection+diodes&pc=MOZI&form=MOZTSB" rel="nofollow">transient protection diodes</a>, and TVS diodes. <br /><br />SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-85578151063719351122015-12-13T13:47:39.660-05:002015-12-13T13:47:39.660-05:00The real issue about their survivability, SiGb, is...The real issue about their survivability, SiGb, is what voltage they can handle without breaking down. Would you put a diode rated for 12V in a 480V system? And recognize that the voltages an EMP will generate are orders of magnitude beyond that.Mark Matisnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-53971527296865369592015-12-12T14:10:05.909-05:002015-12-12T14:10:05.909-05:00Haven't found anything specific to solar panel...Haven't found anything specific to solar panels, but this:<br />http://www.empcommission.org/docs/A2473-EMP_Commission-7MB.pdf<br />includes a rather extensive section on damages to space systems, starting around page 158.<br /><br />Some articles note that solar panels typically operate at low voltage, and that generated voltage by an EMP would drive panel voltage FAR above its normal value. Nobody seems to have done any specific testing for that, however.Mark Matisnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-18010488733102181882015-12-12T10:48:17.850-05:002015-12-12T10:48:17.850-05:00By the way, Mark, do you have any references or da...By the way, Mark, do you have any references or data on that (solar cells being blown by an EMP)? <br /><br />I've been keeping an eye out for info but haven't hit the IEEE pubs. AFAIK, a solar cell is a giant diode, the simplest kind of device there is. With a junction area measured in square inches instead of <b>millionths</b> of a sq.in., my guess is it could survive the surge. (If millionths of a square inch handle surges in thousands of amps, and they do, how much could 40 square inches take?) <br /><br />SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-72195176609528508502015-12-11T17:30:58.896-05:002015-12-11T17:30:58.896-05:00Adn Reg T, I would not count on a PV system workin...Adn <b>Reg T</b>, I would not count on a PV system working after any significant EMP. Maybe they have hardened significantly recently, but if not, they are at least as susceptible as computer-controlled vehicles.Mark Matisnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-14261484784928503812015-12-09T15:55:24.071-05:002015-12-09T15:55:24.071-05:00If'n you ain't one of dem Steve Jobs fanbo...If'n you ain't one of dem Steve Jobs fanbois, youse mights wants ta get ya a Samsung Galaxy S5:<br />https://www.youtube.com/watch?v=RofPY61okSQ&feature=iv&src_vid=t-VekZP9jS0&annotation_id=annotation_460002877<br /><br />Unless dat Injun River where youse goes is much over t'ree feet deep. Or if'n youse kin stay underwater longer that 30 minutes...<br /><br />Their S6, unfortunately, does not seem to claim to be waterproof, however...Mark Matisnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-65049205334258220182015-12-09T10:41:23.703-05:002015-12-09T10:41:23.703-05:00Personally been aggravated wireless charging is so...Personally been aggravated wireless charging is so unpopular.<br />In a first-world problems sort of deal, when I get home I lay my phone on the pad. When I go to bed, I set it on the wireless charging stand, and voila, alarm clock I can see with out lifting it or my head. And each time it is a one handed task, not futzing with a cable and whatever the current fad the connector is.<br />It is more expensive to buy, until I start counting the number of USB cables I've gone through for the car and on the road locations.<br /><br />eliAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-89201183427539362082015-12-08T22:42:54.408-05:002015-12-08T22:42:54.408-05:00I've been watching solar PV prices since 1987,...I've been watching solar PV prices since 1987, and the cost per watt has been coming down for some time. You can now buy quality solar panels for less than a dollar a watt. Inverters are improving, as well as micro-inverters on the panels themselves, which can simplify things and reduce costs, besides not losing your power in the case of a failure of the one and only inverter in a "standard" PV system.<br /><br />It is still expensive, and the "payback" of a system is still a long term item. But - in the light of a possible crash of the economy or other scenario (solar or nuclear EMP destroying grid power?), it has become a viable way for an individual to maintain the ability to pump water from a deep well (the only kind in my rural neck of the woods), refrigerate/freeze food, run radios and lights, and - very important to me - keep an engineered septic system running (sand-filtered system where the ground won't "perk"). Beats the old 5 gallon bucket alternative.<br /><br />There is a lot of very interesting emerging technology on the horizon. Don't know if the "center" will hold long enough to see much of it, although I certainly hope it does.Reg Thttps://www.blogger.com/profile/14099612693763932005noreply@blogger.com