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#71
posted to rec.boats
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Gasoline Availability Good Locally
On Monday, May 17, 2021 at 12:19:06 PM UTC-4, wrote:
On Mon, 17 May 2021 09:20:32 -0400, Keyser Söze wrote: On 5/16/21 7:55 PM, wrote: On Sun, 16 May 2021 14:29:34 -0400, Keyser Söze wrote: On 5/16/21 12:25 PM, wrote: On Sun, 16 May 2021 09:53:07 -0400, Keyser Söze wrote: On 5/15/21 9:02 PM, wrote: This is an all electric house. The only utilities coming in are FPL and the telco. With 5 pumps running off and on, 2 AC units, a water heater, 2 fridges and a few PCs going all the time, I can rack up some KWH. Five pumps? Are you running an aquaculture farm there? We have two heat pumps, but in the winter the main floor of the house is heated via a gas furnace with electric backup. Water heaters are gas, stovetop is gas, fireplaces are gas. 2 pumps for the well. One pool pump, one spa pump for circulation, one R/O booster pump. There is also a jet pump and heater for the spa but those are only on when I am using it. That really makes the meter hum. I can't get gas here or I would have it. OTOH gas isn't all that cheap here and electricity is. (11c /KWH) Teco is still recovering the cost of running a pipe from Tampa and they still haven't expanded into most old neighborhoods. I haven't really looked into it since I can't get it but at my wife's club the snowbirds were complaining that gas was a lot cheaper up there. I remember it being a pretty small bill when I was there. I looked up Maryland...it's in the 11 cents/KWH range in this state, too, on average. Our local company gets: SMECO Energy Rates May 2021 Residential: $0.057873 Plus a couple of "adjustments" and "tariffs" that add about a penny and a half. That is the usage rate but the only real way to look at it is to divide the total bill by the number of KWH used. Last time I checked propane, it was about $2.75 a gallon, but that rate fluctuates widely. Have seen it at $3+ a gallon. Propane can go from a little over $2 a gallon to over $4 here. I don't buy enough to care that much tho. I know after Irma and through most of that winter it was around $4 but I didn't need it enough to pay that much. In the spring I filled my tank for $2.11 "on sale". It is still out there. We have a good number of propane "appliances," and two propane fireplaces. The propane supplier we use is very customer friendly and service-oriented, so it is easy to maintain or upgrade or replace whatever uses their product. When we added the second fireplace a few years ago, the supplier sent out a crew to dig the 3' deep trench between the buried tank for about 75' to where it enters the house, plus the fittings, the hookups and the county inspection. The fittings and hookup were done by a union plumber. My recollection is that the only charge was for the wrapped copper pipe and fittings. I paid about $1500 for the buried tank and the connections for the pool heater and generator (tank, pipe, regulators, permits and labor). I own the tank so I have some flexibility in who I get to fill it. You end up paying for that "free" installation anyway. It's built-in to the price of the propane and the services and the appliances you buy from your dealer that has you locked in. We use very little propane these days. Cooktop, water heater, and 2 fireplaces. I get the tank filled by whoever has the best price, and I usually pit them against each other. Last fill was $2.39/gal. |
#72
posted to rec.boats
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Gasoline Availability Good Locally
On Monday, May 17, 2021 at 12:10:47 PM UTC-4, wrote:
My spa controller is 4xxx CMOS but my pool controller is all relays and switches with a cam timer on a 24 hour gear motor shaft. Power surges will not hurt that although the 4xxx CMOS has lived through 35 years of lightning strikes and power hits. I may have posted this before, but this is a really good product and worth every cent. https://www.amazon.com/Delta-LA302-R-120-240V-Lightning-Arrestor/dp/B006H3U4HS/ref=asc_df_B006H3U4HS/?tag=hyprod-20&linkCode=df0&hvadid=309804813335&hvpos=&hvnetw= g&hvrand=12948758990071981512&hvpone=&hvptwo=&hvqm t=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9010378&hv targid=pla-568919638940&psc=1 I have three on my house... one in one of the two, 200amp breaker boxes, one on the well pump pressure switch, and one in the breaker box for my shop. I've never lost anything to surges, at least that I know of. They do make several different products for different applications. |
#73
posted to rec.boats
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Gasoline Availability Good Locally
On Mon, 17 May 2021 10:10:08 -0700 (PDT), "
wrote: On Monday, May 17, 2021 at 12:10:47 PM UTC-4, wrote: My spa controller is 4xxx CMOS but my pool controller is all relays and switches with a cam timer on a 24 hour gear motor shaft. Power surges will not hurt that although the 4xxx CMOS has lived through 35 years of lightning strikes and power hits. I may have posted this before, but this is a really good product and worth every cent. https://www.amazon.com/Delta-LA302-R-120-240V-Lightning-Arrestor/dp/B006H3U4HS/ref=asc_df_B006H3U4HS/?tag=hyprod-20&linkCode=df0&hvadid=309804813335&hvpos=&hvnetw= g&hvrand=12948758990071981512&hvpone=&hvptwo=&hvqm t=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9010378&hv targid=pla-568919638940&psc=1 I have three on my house... one in one of the two, 200amp breaker boxes, one on the well pump pressure switch, and one in the breaker box for my shop. I've never lost anything to surges, at least that I know of. They do make several different products for different applications. I have several of those MOV protectors in the system along with some point of use protectors. It is important that you have all wires coming into your house protected (cable, phone and power). All should be tied to the same common grounding electrode system with the shortest wire possible. You also need to be sure your grounding electrode system is good. A ground rod or two isn't going to cut it. I have a number of electrodes but the pool and concrete deck is probably the best one. Everything is bonded. |
#75
posted to rec.boats
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Gasoline Availability Good Locally
wrote:
On Sun, 16 May 2021 18:24:15 -0000 (UTC), Bill wrote: wrote: On Sat, 15 May 2021 12:35:41 -0400, "Mr. Luddite" wrote: On 5/15/2021 10:08 AM, wrote: On Saturday, May 15, 2021 at 7:07:22 AM UTC-4, Mr. Luddite wrote: On 5/14/2021 8:34 PM, wrote: On Friday, May 14, 2021 at 8:13:14 PM UTC-4, wrote: On Fri, 14 May 2021 11:35:07 -0700 (PDT), " wrote: On Friday, May 14, 2021 at 2:21:17 PM UTC-4, wrote: On Fri, 14 May 2021 07:08:29 -0400, "Mr. Luddite" wrote: On 5/13/2021 11:50 PM, wrote: On Wed, 12 May 2021 10:51:07 -0400, Keyser Söze wrote: Three of the four gas stations in our area had product to sell and no lines. The big volume dealer -WaWa- was sold out and awaiting a tank truck delivery later today. We had spot shortages here and we don't even get our gas from that pipe. Nobody in the peninsula does. It was just panic buying AKA a media driven emergency. Now that everyone has every gas can and tupperware bowl full of gas, supplies are recovering. I still got gas yesterday at my regular station no line no problem regular price. Cracks me up though. Responding to the alternative methods to deliver fuel, Biden's Energy Secretary stated that the pipelines are the better way to transport it even though her boss axed the Keystone pipeline. Then she thumbed her typical liberal nose at the public by saying that if people used electric vehicles, they wouldn't be experiencing these fuel shortages. She also happens to own stock in an electric bus manufacturer that Biden visited to promote. The value of her stock holdings are potentially worth $ millions and she has not divested her holdings even though there's a conflict of interest issue. But what really cracks me up is none of these electric vehicle advocates ever mention where the energy comes from to charge up their electric vehicle batteries. The vast bulk of it is generated by fossil fuel plants. Plus, whenever energy is transformed from one state to another there are losses involved. Laws of physics prevail. There are also the I2R losses in the transmission lines. A while ago one of my inspector trade rags had a story "How hot are those conductors?" talking about how hot some transmission lines run and how that affects line sag but the fact remains that is waste heat going into the air. It is hard to get the utilities to say how much power is wasted in transmission and the crazy bookkeeping they use on the grid makes those numbers hard to actually believe when you see them but it is a pretty big number if your power is coming from very far away. I2R still wins in the end. I'm sure you know that's the reason the transmission lines are run at such a high voltage. It minimizes he losses, but there are still some. The company I used to work for put in some equipment for a regional power company some years ago. They told me about an incident where, in the middle of the summer in a coastal SC area, a transmission line that was hot and sagging separated at a badly crimped barrel "butt" splice. No one was there to see it, but when it separated it produced a fireball that, when it hit the ground, blew a big enough hole to drive a truck down into and hide it. They said there were clumps of fused sand laying around. That would have been cool to see, just not too close up. Watts is watts (is 3.4BTU) , if you have 300 miles of transmission line that is running at 40-50c above ambient air, you are wasting a lot of watts. When you consider transmission lines typically carry two or 3 triplexes that starts looking more like 1800-2700 miles of wire to go 300 miles. You don't usually see a lot of snow around transformer farms either. They do twist the triplexes to minimize parasitic losses but they are still there or you wouldn't be hearing all the concerns about power line radiation. I have tried several times to find out what the difference is between power generated and power actually billed to a customer but those numbers are hard to come by, even by people I know, close to the business. As I said, the screwy grid bookkeeping makes it hard to get a real answer. Understood, but as you point out the loss equation is I2R. If you make the I (current) smaller, the loss is smaller. That's what raising the voltage does (P=E x I). Double the voltage, then halve the current for the same power (watts). That reduces the IR loss. Math and physics are cool. My electrical knowledge is fuzzy at best now but I also don't think there is a huge loss due to inductive or electromagnetic radiation. The freq is too low at 60 Hz. At high frequencies (RF range) electromagnetic radiation is an issue which is why transmission lines are shielded and are designed to have a uniform characteristic impedance. Inductive and capacitive reactance are involved that define the transmission line's impedence. DC has no issues with this. There's no "impedence" (which is a reactive component and only applies to AC) to deal with. There's only pure resistance. -- This email has been checked for viruses by AVG. https://www.avg.com === If you read through the sources that I cited there is a great deal of information on why conversion to DC makes sense on long high voltage lines. One of the loss factors mentioned was inductive reactance (2pifl). On long transmission lines there is enough inductance to cause power loss even at 60Hz. https://engineering.stackexchange.co...etter-ac-or-dc https://www.powermag.com/benefits-of...ssion-systems/ https://energycentral.com/c/ec/ac-vs...lectrical-grid I don't question what they are saying. I never dealt with high voltage transmission lines other than for high powered transmitters that were operating in the RF range. I recall in school however that for all intents and purposes AC at 60 Hz was like DC other than the fact that in transformers and coils it has inductive qualities if in very close proximity or, in the case of a transformer, wound and "cutting" into an iron core. We used to deal with it all the time as "hum" induced into low voltage signal lines, for sure though. As for reactance ... 60 Hz was just too low of a freq to be concerned about. My instructor would scold us if we used the term "impedance" in a DC circuit instead of pure resistance. At much higher voltages and much longer transmission lines it apparently has reactive qualities though according to your cites. As I pointed out they actually twist the triplex to mitigate those losses a little or at least balance the loss but at 60 hz one twist per mile or so seems to be all they need. You will see it if you drive along next to a transmission line and look tho. The losses must be a lot worse on the single phase wye distribution in front of most people's houses tho. Seems as if over the years, people have powered there places with inductive power from power lines. Run insulated fences under the lines crossing their land. As I said in another post, they had 200 amps power induced in the ground lines by the break in a 500kv line here. I have never been able to duplicate any of that. Fluorescent lamps do not glow under my 230kv power line, even when I did string a 100' insulated wire and connected it to the lamp. I was hoping I could get enough to light up my boat without stringing a 120v wire down there but I could never get it to work. I bet that "200 amps" was actually 200 volts that went away as soon as you attached any significant load. I can get crazy high readings on a digital meter and a piece of wire but on an analog meter, not so much. Nah, the PG&E friend said they were seeing 200 amps in the ground line. But this is a probably a 500 mile long 500kv line. |
#76
posted to rec.boats
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Gasoline Availability Good Locally
wrote:
On Sun, 16 May 2021 18:24:16 -0000 (UTC), Bill wrote: wrote: On Sun, 16 May 2021 09:53:07 -0400, Keyser Söze wrote: On 5/15/21 9:02 PM, wrote: This is an all electric house. The only utilities coming in are FPL and the telco. With 5 pumps running off and on, 2 AC units, a water heater, 2 fridges and a few PCs going all the time, I can rack up some KWH. Five pumps? Are you running an aquaculture farm there? We have two heat pumps, but in the winter the main floor of the house is heated via a gas furnace with electric backup. Water heaters are gas, stovetop is gas, fireplaces are gas. 2 pumps for the well. One pool pump, one spa pump for circulation, one R/O booster pump. There is also a jet pump and heater for the spa but those are only on when I am using it. That really makes the meter hum. I can't get gas here or I would have it. OTOH gas isn't all that cheap here and electricity is. (11c /KWH) Teco is still recovering the cost of running a pipe from Tampa and they still haven't expanded into most old neighborhoods. I haven't really looked into it since I can't get it but at my wife's club the snowbirds were complaining that gas was a lot cheaper up there. I remember it being a pretty small bill when I was there. Gas here used to run about $10 a month, with just the heater. Now with heater (more efficient model) and a gas dryer, the prices have soared. I pay about $120 average a month in gas. As electric Is very pricey. I get an Electric Vehicle rate and pay almost 13 cents a KWh at night, but 42.5 cents peak rate times. If I charged my car during peak times, I figured the gas equivalent is over $4 a gallon. I think I would get an electric dryer and only do laundry at night. ;-) We used to have electric and went to gas when it was cheaper. Before the solar install. Maybe you stay up 11 pm to 6 am for laundry, but not going to make wife. Happy wife, happy life. |
#77
posted to rec.boats
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Gasoline Availability Good Locally
Mr. Luddite wrote:
On 5/16/2021 2:28 PM, Bill wrote: wrote: On Saturday, May 15, 2021 at 9:09:11 PM UTC-4, wrote: On Sat, 15 May 2021 12:35:41 -0400, "Mr. Luddite" wrote: On 5/15/2021 10:08 AM, wrote: On Saturday, May 15, 2021 at 7:07:22 AM UTC-4, Mr. Luddite wrote: On 5/14/2021 8:34 PM, wrote: On Friday, May 14, 2021 at 8:13:14 PM UTC-4, wrote: On Fri, 14 May 2021 11:35:07 -0700 (PDT), " wrote: On Friday, May 14, 2021 at 2:21:17 PM UTC-4, wrote: On Fri, 14 May 2021 07:08:29 -0400, "Mr. Luddite" wrote: On 5/13/2021 11:50 PM, wrote: On Wed, 12 May 2021 10:51:07 -0400, Keyser Söze wrote: Three of the four gas stations in our area had product to sell and no lines. The big volume dealer -WaWa- was sold out and awaiting a tank truck delivery later today. We had spot shortages here and we don't even get our gas from that pipe. Nobody in the peninsula does. It was just panic buying AKA a media driven emergency. Now that everyone has every gas can and tupperware bowl full of gas, supplies are recovering. I still got gas yesterday at my regular station no line no problem regular price. Cracks me up though. Responding to the alternative methods to deliver fuel, Biden's Energy Secretary stated that the pipelines are the better way to transport it even though her boss axed the Keystone pipeline. Then she thumbed her typical liberal nose at the public by saying that if people used electric vehicles, they wouldn't be experiencing these fuel shortages. She also happens to own stock in an electric bus manufacturer that Biden visited to promote. The value of her stock holdings are potentially worth $ millions and she has not divested her holdings even though there's a conflict of interest issue. But what really cracks me up is none of these electric vehicle advocates ever mention where the energy comes from to charge up their electric vehicle batteries. The vast bulk of it is generated by fossil fuel plants. Plus, whenever energy is transformed from one state to another there are losses involved. Laws of physics prevail. There are also the I2R losses in the transmission lines. A while ago one of my inspector trade rags had a story "How hot are those conductors?" talking about how hot some transmission lines run and how that affects line sag but the fact remains that is waste heat going into the air. It is hard to get the utilities to say how much power is wasted in transmission and the crazy bookkeeping they use on the grid makes those numbers hard to actually believe when you see them but it is a pretty big number if your power is coming from very far away. I2R still wins in the end. I'm sure you know that's the reason the transmission lines are run at such a high voltage. It minimizes he losses, but there are still some. The company I used to work for put in some equipment for a regional power company some years ago. They told me about an incident where, in the middle of the summer in a coastal SC area, a transmission line that was hot and sagging separated at a badly crimped barrel "butt" splice. No one was there to see it, but when it separated it produced a fireball that, when it hit the ground, blew a big enough hole to drive a truck down into and hide it. They said there were clumps of fused sand laying around. That would have been cool to see, just not too close up. Watts is watts (is 3.4BTU) , if you have 300 miles of transmission line that is running at 40-50c above ambient air, you are wasting a lot of watts. When you consider transmission lines typically carry two or 3 triplexes that starts looking more like 1800-2700 miles of wire to go 300 miles. You don't usually see a lot of snow around transformer farms either. They do twist the triplexes to minimize parasitic losses but they are still there or you wouldn't be hearing all the concerns about power line radiation. I have tried several times to find out what the difference is between power generated and power actually billed to a customer but those numbers are hard to come by, even by people I know, close to the business. As I said, the screwy grid bookkeeping makes it hard to get a real answer. Understood, but as you point out the loss equation is I2R. If you make the I (current) smaller, the loss is smaller. That's what raising the voltage does (P=E x I). Double the voltage, then halve the current for the same power (watts). That reduces the IR loss. Math and physics are cool. My electrical knowledge is fuzzy at best now but I also don't think there is a huge loss due to inductive or electromagnetic radiation. The freq is too low at 60 Hz. At high frequencies (RF range) electromagnetic radiation is an issue which is why transmission lines are shielded and are designed to have a uniform characteristic impedance. Inductive and capacitive reactance are involved that define the transmission line's impedence. DC has no issues with this. There's no "impedence" (which is a reactive component and only applies to AC) to deal with. There's only pure resistance. -- This email has been checked for viruses by AVG. https://www.avg.com === If you read through the sources that I cited there is a great deal of information on why conversion to DC makes sense on long high voltage lines. One of the loss factors mentioned was inductive reactance (2pifl). On long transmission lines there is enough inductance to cause power loss even at 60Hz. https://engineering.stackexchange.co...etter-ac-or-dc https://www.powermag.com/benefits-of...ssion-systems/ https://energycentral.com/c/ec/ac-vs...lectrical-grid I don't question what they are saying. I never dealt with high voltage transmission lines other than for high powered transmitters that were operating in the RF range. I recall in school however that for all intents and purposes AC at 60 Hz was like DC other than the fact that in transformers and coils it has inductive qualities if in very close proximity or, in the case of a transformer, wound and "cutting" into an iron core. We used to deal with it all the time as "hum" induced into low voltage signal lines, for sure though. As for reactance ... 60 Hz was just too low of a freq to be concerned about. My instructor would scold us if we used the term "impedance" in a DC circuit instead of pure resistance. At much higher voltages and much longer transmission lines it apparently has reactive qualities though according to your cites. As I pointed out they actually twist the triplex to mitigate those losses a little or at least balance the loss but at 60 hz one twist per mile or so seems to be all they need. You will see it if you drive along next to a transmission line and look tho. The losses must be a lot worse on the single phase wye distribution in front of most people's houses tho. === I believe the losses due to EMF radiation and inductive reactance are really only a factor on very long distribution lines. The articles that I cited also mentioned another interesting advantage to direct current distribution: Phase matching between networks. The DC to AC conversion process makes that easy. The problem I see is the reliability of the conversion equipment. Transformers are super durable, especially in power generation and oil cooled. DC to AC conversion has losses, but also, how do you keep the equipment from melting. You would be hard pressed to have semiconductors work, except in controls. Probably need vacuum tubes for power handlin I was thinking about the hacking of critical infrastructure systems last night. One solution might be to go back to analog control systems with control relay logic instead of solid state controls running on computer software that is tied to the Internet for "wireless" system controls. Back when the US military was working on "hardening" systems in ships and aircraft against EMF from a nuclear blast the Soviets had a much simpler solution. Their systems ran mostly on vacuum tube technology and were pretty much immune to electromagnetic radiation. It's why today there are few (if any) vacuum tubes manufactured in the USA. Most all come from Russia. Russia even ran mini tubes in their war planes 20 years ago, |
#78
posted to rec.boats
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Gasoline Availability Good Locally
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#79
posted to rec.boats
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Gasoline Availability Good Locally
wrote:
On Mon, 17 May 2021 06:13:15 -0400, "Mr. Luddite" wrote: On 5/16/2021 2:28 PM, Bill wrote: wrote: On Saturday, May 15, 2021 at 9:09:11 PM UTC-4, wrote: On Sat, 15 May 2021 12:35:41 -0400, "Mr. Luddite" wrote: On 5/15/2021 10:08 AM, wrote: On Saturday, May 15, 2021 at 7:07:22 AM UTC-4, Mr. Luddite wrote: On 5/14/2021 8:34 PM, wrote: On Friday, May 14, 2021 at 8:13:14 PM UTC-4, wrote: On Fri, 14 May 2021 11:35:07 -0700 (PDT), " wrote: On Friday, May 14, 2021 at 2:21:17 PM UTC-4, wrote: On Fri, 14 May 2021 07:08:29 -0400, "Mr. Luddite" wrote: On 5/13/2021 11:50 PM, wrote: On Wed, 12 May 2021 10:51:07 -0400, Keyser Söze wrote: Three of the four gas stations in our area had product to sell and no lines. The big volume dealer -WaWa- was sold out and awaiting a tank truck delivery later today. We had spot shortages here and we don't even get our gas from that pipe. Nobody in the peninsula does. It was just panic buying AKA a media driven emergency. Now that everyone has every gas can and tupperware bowl full of gas, supplies are recovering. I still got gas yesterday at my regular station no line no problem regular price. Cracks me up though. Responding to the alternative methods to deliver fuel, Biden's Energy Secretary stated that the pipelines are the better way to transport it even though her boss axed the Keystone pipeline. Then she thumbed her typical liberal nose at the public by saying that if people used electric vehicles, they wouldn't be experiencing these fuel shortages. She also happens to own stock in an electric bus manufacturer that Biden visited to promote. The value of her stock holdings are potentially worth $ millions and she has not divested her holdings even though there's a conflict of interest issue. But what really cracks me up is none of these electric vehicle advocates ever mention where the energy comes from to charge up their electric vehicle batteries. The vast bulk of it is generated by fossil fuel plants. Plus, whenever energy is transformed from one state to another there are losses involved. Laws of physics prevail. There are also the I2R losses in the transmission lines. A while ago one of my inspector trade rags had a story "How hot are those conductors?" talking about how hot some transmission lines run and how that affects line sag but the fact remains that is waste heat going into the air. It is hard to get the utilities to say how much power is wasted in transmission and the crazy bookkeeping they use on the grid makes those numbers hard to actually believe when you see them but it is a pretty big number if your power is coming from very far away. I2R still wins in the end. I'm sure you know that's the reason the transmission lines are run at such a high voltage. It minimizes he losses, but there are still some. The company I used to work for put in some equipment for a regional power company some years ago. They told me about an incident where, in the middle of the summer in a coastal SC area, a transmission line that was hot and sagging separated at a badly crimped barrel "butt" splice. No one was there to see it, but when it separated it produced a fireball that, when it hit the ground, blew a big enough hole to drive a truck down into and hide it. They said there were clumps of fused sand laying around. That would have been cool to see, just not too close up. Watts is watts (is 3.4BTU) , if you have 300 miles of transmission line that is running at 40-50c above ambient air, you are wasting a lot of watts. When you consider transmission lines typically carry two or 3 triplexes that starts looking more like 1800-2700 miles of wire to go 300 miles. You don't usually see a lot of snow around transformer farms either. They do twist the triplexes to minimize parasitic losses but they are still there or you wouldn't be hearing all the concerns about power line radiation. I have tried several times to find out what the difference is between power generated and power actually billed to a customer but those numbers are hard to come by, even by people I know, close to the business. As I said, the screwy grid bookkeeping makes it hard to get a real answer. Understood, but as you point out the loss equation is I2R. If you make the I (current) smaller, the loss is smaller. That's what raising the voltage does (P=E x I). Double the voltage, then halve the current for the same power (watts). That reduces the IR loss. Math and physics are cool. My electrical knowledge is fuzzy at best now but I also don't think there is a huge loss due to inductive or electromagnetic radiation. The freq is too low at 60 Hz. At high frequencies (RF range) electromagnetic radiation is an issue which is why transmission lines are shielded and are designed to have a uniform characteristic impedance. Inductive and capacitive reactance are involved that define the transmission line's impedence. DC has no issues with this. There's no "impedence" (which is a reactive component and only applies to AC) to deal with. There's only pure resistance. -- This email has been checked for viruses by AVG. https://www.avg.com === If you read through the sources that I cited there is a great deal of information on why conversion to DC makes sense on long high voltage lines. One of the loss factors mentioned was inductive reactance (2pifl). On long transmission lines there is enough inductance to cause power loss even at 60Hz. https://engineering.stackexchange.co...etter-ac-or-dc https://www.powermag.com/benefits-of...ssion-systems/ https://energycentral.com/c/ec/ac-vs...lectrical-grid I don't question what they are saying. I never dealt with high voltage transmission lines other than for high powered transmitters that were operating in the RF range. I recall in school however that for all intents and purposes AC at 60 Hz was like DC other than the fact that in transformers and coils it has inductive qualities if in very close proximity or, in the case of a transformer, wound and "cutting" into an iron core. We used to deal with it all the time as "hum" induced into low voltage signal lines, for sure though. As for reactance ... 60 Hz was just too low of a freq to be concerned about. My instructor would scold us if we used the term "impedance" in a DC circuit instead of pure resistance. At much higher voltages and much longer transmission lines it apparently has reactive qualities though according to your cites. As I pointed out they actually twist the triplex to mitigate those losses a little or at least balance the loss but at 60 hz one twist per mile or so seems to be all they need. You will see it if you drive along next to a transmission line and look tho. The losses must be a lot worse on the single phase wye distribution in front of most people's houses tho. === I believe the losses due to EMF radiation and inductive reactance are really only a factor on very long distribution lines. The articles that I cited also mentioned another interesting advantage to direct current distribution: Phase matching between networks. The DC to AC conversion process makes that easy. The problem I see is the reliability of the conversion equipment. Transformers are super durable, especially in power generation and oil cooled. DC to AC conversion has losses, but also, how do you keep the equipment from melting. You would be hard pressed to have semiconductors work, except in controls. Probably need vacuum tubes for power handlin I was thinking about the hacking of critical infrastructure systems last night. One solution might be to go back to analog control systems with control relay logic instead of solid state controls running on computer software that is tied to the Internet for "wireless" system controls. Back when the US military was working on "hardening" systems in ships and aircraft against EMF from a nuclear blast the Soviets had a much simpler solution. Their systems ran mostly on vacuum tube technology and were pretty much immune to electromagnetic radiation. It's why today there are few (if any) vacuum tubes manufactured in the USA. Most all come from Russia. My spa controller is 4xxx CMOS but my pool controller is all relays and switches with a cam timer on a 24 hour gear motor shaft. Power surges will not hurt that although the 4xxx CMOS has lived through 35 years of lightning strikes and power hits. Means you have a great power supply on the cmos. We had a disk controller in the 1980’s that had pass transistors. Passed lots of lightning glitches through. We in engineering were going to replace new production with switching power supplies, but the idiot VP of manufacturing paid a premium for the crappy supplies to continue production. |
#80
posted to rec.boats
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Gasoline Availability Good Locally
On Mon, 17 May 2021 18:04:26 -0000 (UTC), Bill
wrote: wrote: On Sun, 16 May 2021 18:24:15 -0000 (UTC), Bill wrote: wrote: On Sat, 15 May 2021 12:35:41 -0400, "Mr. Luddite" wrote: On 5/15/2021 10:08 AM, wrote: On Saturday, May 15, 2021 at 7:07:22 AM UTC-4, Mr. Luddite wrote: On 5/14/2021 8:34 PM, wrote: On Friday, May 14, 2021 at 8:13:14 PM UTC-4, wrote: On Fri, 14 May 2021 11:35:07 -0700 (PDT), " wrote: On Friday, May 14, 2021 at 2:21:17 PM UTC-4, wrote: On Fri, 14 May 2021 07:08:29 -0400, "Mr. Luddite" wrote: On 5/13/2021 11:50 PM, wrote: On Wed, 12 May 2021 10:51:07 -0400, Keyser Söze wrote: Three of the four gas stations in our area had product to sell and no lines. The big volume dealer -WaWa- was sold out and awaiting a tank truck delivery later today. We had spot shortages here and we don't even get our gas from that pipe. Nobody in the peninsula does. It was just panic buying AKA a media driven emergency. Now that everyone has every gas can and tupperware bowl full of gas, supplies are recovering. I still got gas yesterday at my regular station no line no problem regular price. Cracks me up though. Responding to the alternative methods to deliver fuel, Biden's Energy Secretary stated that the pipelines are the better way to transport it even though her boss axed the Keystone pipeline. Then she thumbed her typical liberal nose at the public by saying that if people used electric vehicles, they wouldn't be experiencing these fuel shortages. She also happens to own stock in an electric bus manufacturer that Biden visited to promote. The value of her stock holdings are potentially worth $ millions and she has not divested her holdings even though there's a conflict of interest issue. But what really cracks me up is none of these electric vehicle advocates ever mention where the energy comes from to charge up their electric vehicle batteries. The vast bulk of it is generated by fossil fuel plants. Plus, whenever energy is transformed from one state to another there are losses involved. Laws of physics prevail. There are also the I2R losses in the transmission lines. A while ago one of my inspector trade rags had a story "How hot are those conductors?" talking about how hot some transmission lines run and how that affects line sag but the fact remains that is waste heat going into the air. It is hard to get the utilities to say how much power is wasted in transmission and the crazy bookkeeping they use on the grid makes those numbers hard to actually believe when you see them but it is a pretty big number if your power is coming from very far away. I2R still wins in the end. I'm sure you know that's the reason the transmission lines are run at such a high voltage. It minimizes he losses, but there are still some. The company I used to work for put in some equipment for a regional power company some years ago. They told me about an incident where, in the middle of the summer in a coastal SC area, a transmission line that was hot and sagging separated at a badly crimped barrel "butt" splice. No one was there to see it, but when it separated it produced a fireball that, when it hit the ground, blew a big enough hole to drive a truck down into and hide it. They said there were clumps of fused sand laying around. That would have been cool to see, just not too close up. Watts is watts (is 3.4BTU) , if you have 300 miles of transmission line that is running at 40-50c above ambient air, you are wasting a lot of watts. When you consider transmission lines typically carry two or 3 triplexes that starts looking more like 1800-2700 miles of wire to go 300 miles. You don't usually see a lot of snow around transformer farms either. They do twist the triplexes to minimize parasitic losses but they are still there or you wouldn't be hearing all the concerns about power line radiation. I have tried several times to find out what the difference is between power generated and power actually billed to a customer but those numbers are hard to come by, even by people I know, close to the business. As I said, the screwy grid bookkeeping makes it hard to get a real answer. Understood, but as you point out the loss equation is I2R. If you make the I (current) smaller, the loss is smaller. That's what raising the voltage does (P=E x I). Double the voltage, then halve the current for the same power (watts). That reduces the IR loss. Math and physics are cool. My electrical knowledge is fuzzy at best now but I also don't think there is a huge loss due to inductive or electromagnetic radiation. The freq is too low at 60 Hz. At high frequencies (RF range) electromagnetic radiation is an issue which is why transmission lines are shielded and are designed to have a uniform characteristic impedance. Inductive and capacitive reactance are involved that define the transmission line's impedence. DC has no issues with this. There's no "impedence" (which is a reactive component and only applies to AC) to deal with. There's only pure resistance. -- This email has been checked for viruses by AVG. https://www.avg.com === If you read through the sources that I cited there is a great deal of information on why conversion to DC makes sense on long high voltage lines. One of the loss factors mentioned was inductive reactance (2pifl). On long transmission lines there is enough inductance to cause power loss even at 60Hz. https://engineering.stackexchange.co...etter-ac-or-dc https://www.powermag.com/benefits-of...ssion-systems/ https://energycentral.com/c/ec/ac-vs...lectrical-grid I don't question what they are saying. I never dealt with high voltage transmission lines other than for high powered transmitters that were operating in the RF range. I recall in school however that for all intents and purposes AC at 60 Hz was like DC other than the fact that in transformers and coils it has inductive qualities if in very close proximity or, in the case of a transformer, wound and "cutting" into an iron core. We used to deal with it all the time as "hum" induced into low voltage signal lines, for sure though. As for reactance ... 60 Hz was just too low of a freq to be concerned about. My instructor would scold us if we used the term "impedance" in a DC circuit instead of pure resistance. At much higher voltages and much longer transmission lines it apparently has reactive qualities though according to your cites. As I pointed out they actually twist the triplex to mitigate those losses a little or at least balance the loss but at 60 hz one twist per mile or so seems to be all they need. You will see it if you drive along next to a transmission line and look tho. The losses must be a lot worse on the single phase wye distribution in front of most people's houses tho. Seems as if over the years, people have powered there places with inductive power from power lines. Run insulated fences under the lines crossing their land. As I said in another post, they had 200 amps power induced in the ground lines by the break in a 500kv line here. I have never been able to duplicate any of that. Fluorescent lamps do not glow under my 230kv power line, even when I did string a 100' insulated wire and connected it to the lamp. I was hoping I could get enough to light up my boat without stringing a 120v wire down there but I could never get it to work. I bet that "200 amps" was actually 200 volts that went away as soon as you attached any significant load. I can get crazy high readings on a digital meter and a piece of wire but on an analog meter, not so much. Nah, the PG&E friend said they were seeing 200 amps in the ground line. But this is a probably a 500 mile long 500kv line. 200 amps into what kind of load? |
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