Post by papaof2 on Feb 10, 2020 19:47:52 GMT -6
Prolog
Not every "End of My World" event starts with a bang. Some of them occur while you're asleep and tomorrow's world isn't even close to yesterday's world. Others occur quietly while you're awake, with little or no indication of their total impact. This story starts with one of those quiet events.
Day 1
The sudden silence in Eclectic, Alabama at 11:30PM on an August evening isn't deafening but it is suspicious. I had just checked the 1800 mile weather radar on weather.com and there's no storm activity within 200 miles of us. No lightning, no thunder, no 'Thump!' of a tree falling or a vehicle hitting a power pole or the bigger 'THUMP!' of an aircraft hitting the ground. Just the light by my chair going out and the fan on the dehumidifier in the kitchen coasting to a stop - and not the usual flicker of power off, on, off, on, off to stay.
Use the Fenix E12 in my pocket to light my way to get the LED head light off the knob of the door to the basement stairs so I'll have hands-free light to make my way through the house - none of the LED nightlights are on without power but the battery-powered motion sensor lights in the hall and on the basement stairs will still work. Try to check the outage map for the electric co-op and there's no internet connectivity from my laptop. I know the Uverse router and the 24 port network switch still have power as I can connect to the Raspberry Pi web server on my home network, which also means all of the network's UPS units are operational. Try the data link on the cell phone and I get a somewhat slow connection but at least some parts of the internet are still there. The co-op's power outage map has the red fill for "More than 350 meters out" on all of their substations. I'll be back to check the percent out at each substation later, as that many outages swamp their outage server and it could be several hours before they have accurate numbers - if that server's backup power lasts long enough. Right now I need to get my "Wait until daylight" backup power system going to power the fridge and a few lights now and the freezer in eight or ten hours if commercial power is still out in the morning.
Where did "Wait until daylight" come from? It's a small solar-charged system that's good for eight to 20 hours depending on the season but it does provide enough power that there's no need for me to be out in a thunderstorm or in the dark at 30F and shoveling my way through seven inches of snow to get a gasoline generator out of the equipment shed. So it's my "Wait until daylight" backup system.
To the basement. Throw the breaker that connects the 2000 watts continuous pure sine wave inverter to the battery bank and turn on the inverter. It does soft-start, ramping its output gradually up to 120 volts AC, so let it get to full output before putting a load on it. Plug a Kill-A-Watt into the inverter so I can monitor the power used, then plug the 12 gauge extension cord into the Kill-A-Watt and run that cord over to the Gen-Tran transfer switch. For now, just power the fridge and some kitchen counter outlets and the LED lights over that counter. Run an extension cord over to the UPS units that keep the network powered so the network has ongoing power and the UPS units can be recharged for future use, if needed. If Uverse is still down in an hour, I'll turn that router off to save a little power (it's "only" 16 watts, but that's 16 watts times 24 hours = 384 watt hours (WH) or 384 / 12 = 32AH from the 12 volt battery bank, plus turn off the DVR for another 20 watts of savings - you do the math for the 24 hour savings). Lots of small loads can make a big difference in the total runtime of the battery backup.
Set a battery-powered alarm clock to wake my wife in the morning. Then put a battery-powered nightlight (actually another Fenix E12 flashlight at its lowest setting and good for 40+ hours on a single alkaline AA cell) in the master bath and turn it on in case she gets up during the night. There's a flashlight on the nightstand by her side of the bed but that's not something she'll think about getting unless she notices that the clocks in the bedroom are dark. Easier to have the E12 as a nightlight in the bathroom and leave the door open a crack.
Get out a grill lighter and put it by the gas cooktop, plus the LED light with magnetic base that can stick to the side of the microwave oven and light the cooking surface below it. There's a hand-crank plus USB rechargeable area light on top of the fridge and it can provide enough light to get out additional lighting for cooking, if needed. Most of the lower cabinets have battery-powered, door-operated LED lighting so anything there is still easily found. There's a two D-cell LED flashlight on the counter for lighting the upper cabinets if needed and that can provide light for a long time.
Write her a note about when power went off and that the fridge has power but she won't have power for the blow dryer, the curling iron, the coffeemaker, the microwave oven or the garage door opener unless I get out a gasoline generator which can handle that much additional load - and she'll have to wake me in time for that if she's planning to go somewhere in the morning. There are no entries for the day on the calendar on the fridge but not everything makes it to that calendar. Get some things out of the pantry for her breakfast and go back to writing my in-progress book. I'm something of a night owl when writing and it could be in the wee hours before I get to bed. The laptop's battery is good for a couple of hours and I can plug it in at one of the kitchen counter outlets if it needs to be recharged before my muse runs out of words.
---
Stopped writing long enough to refill my glass of decaf tea (it's well after midnight, so I don't need caffeine) and used my phone to check Fox and CNN online. All they have to say is "Massive power outage leaves Southeastern US in the dark" and their maps have everything east of the Mississippi River and south of the Kentucky-Tennessee border affected. No reason given for the outage and no mention of prospects for restoration. Not even CNN's news fabricators are saying anything. Isn't that reassuring?
Checked the Uverse connection and no internet, no TV, no landline phone. It failed like that during a snow-caused outage a couple of years ago and it seems they've not improved their backup power capability. Turn off that bit of the network and the UPS that powers it and plan to check it again in an hour or two. At least I can keep the cell phone charged and hope that the nearest cell tower has plenty of backup power. I know the central office that tower connects to has backup: an autostart diesel generator and several weeks of fuel.
Thinking of fuel. We'll be OK if there's enough sun to recharge the battery bank tomorrow but the usual 20 gallons of treated backup fuel is down to about 16 gallons and we'd need something over a gallon a day to run things and charge the battery bank with the inverter generator if there's little or no sun. However, lack of sun is not likely to be a problem in August. I may need to get the rest of the solar panels outside. My solar backup system is mostly a stealth project, with one 250 watt panel set up behind the house where it's almost hidden. If we need maximum solar power for several days, some of the other 1560 watts of solar panels will need to be added depending on the amount of sun and our usage. The Kill-A-Watt on the inverter will tell me how much power we're using, both instantaneous and cumulative, so I'll know how much solar to add or if a gasoline generator is needed - or both. There's also an amp-hour (AH) meter on the feed from the battery bank so I'll know 1) how much the battery bank has been discharged and, from that number, when to shut down the inverter to protect the batteries and 2) how much power has been put back into the batteries by the sun or a generator or both.
Battery voltage is NOT a good indicator of a lead-acid battery's state of charge (SOC) or depth of discharge (DOD), but the actual AH used and restored are an excellent indicator. Charging any battery isn't 100% efficient, with lead-acid charging being an average of 85% efficient over a full charge cycle but that efficiency drops below 60% when 80% charge is reached and below 50% when 90% charge is reached, so the last few percent of a charge can take "forever". Effectively, the battery needs to be charged with 107-115% of the amount it was discharged; in other words, 100AH used will require 107-115AH of replacement depending on the condition of the batteries.
There's nothing wrong with the battery bank, that's just the way the lead-acid chemistry works. There's an online paper on that from C&D Technologies: www.cdtechno.com/pdf/ref/41_2128_0212.pdf
Knowing how much power was removed from the battery bank, I can combine solar plus generator power to ensure that enough power is replaced before sunset - no generators running after dark here except in rare circumstances. I've had more than one five gallon can of gasoline (and kerosene) "disappear" overnight and I certainly don't want that to happen to a generator when commercial AC is out with neither explanation nor expected restoration time.
For those who may think lead-acid batteries are ancient technology and want to know why my battery bank isn't lithium ion or LiFePO4 or maybe LTO, there's a dollars and sense answer. I replaced the previous lead-acid battery bank this year with 420AH of 15 month old AGM batteries that still test as new for $305. I limit the discharge level to 50% (210AH) for maximum battery life. Amazon wants $949 for one 12 volt 100AH Battleborn LiFePO4 battery or about $2000 for almost the same capacity as what I have in AGMs. I don't think that expense makes sense for my purposes, as I can replace the AGMs four more times (or about 20 years' worth) for several hundred dollars less than that and, while the Battleborn has a ten year warranty, they would need to be replaced in less than 20 years. For daily use, the Battleborn's 3,000 charge/discharge cycles would give 8.2 years of cycle life. My AGM batteries would likely only provide 1,000 cycles at the 200AH discharge or 2.73 years of cycle life. That's 33% of the cycle life but at 16% of the cost. The dollars win out in my use for occasional backup power but not for daily primary power. The Battleborn is about half the weight of the AGM (not the "1/3 the weight" often claimed in their ads) which might be important in an RV or boat but not when installed in the basement of a brick house. From my experience with lithium-based batteries in laptop computers, discharging them more than 80% quickly impacts their cycle life so I would only be discharging lithium batteries a maximum of 80% (regardless of the manufacturer's claims that 100% discharge is fine) which means that two 100AH Battleborn batteries would actually provide 160AH of power, which is only 76% of the 210AH the lead-acid AGM batteries provide when only discharged 50%. You need the background information to be able to do the math for YOUR situation when planning backup power. If I used 210AH from the backup system once a week, the lead-acid batteries would theoretically last 19 years. (Do the math: at 1 cycle per week, we get 1000 cycles / 52 weeks = 19.2 years.) However, even well-cared-for AGM batteries (other than the very expensive ones) rarely last more than five to seven years. The ones I replaced were a few months short of 9 years old, so I got much better than average battery life. However, I'm also very careful with my batteries. I replaced the battery in my truck at 5 1/2 years because to my ear the starter was turning a little slow. A year later, that battery is in the basement as a power source for testing inverters and it still tests at greater than 95% capacity. If the new set of AGMs lasts five years, I'll have spent $305 / 60 months = $5.10/month for backup power. If they last nine years, I'll have spent $305 / 108 = $2.84/month. As the ads for other things say, "Just pennies a day". The solar panels and charge controllers are not included in that price as the panels typically have a 25 year life (to 80% of original output) and - barring a lightning strike - the charge controllers are very lightly loaded and should last more than ten years.
---
Not every "End of My World" event starts with a bang. Some of them occur while you're asleep and tomorrow's world isn't even close to yesterday's world. Others occur quietly while you're awake, with little or no indication of their total impact. This story starts with one of those quiet events.
Day 1
The sudden silence in Eclectic, Alabama at 11:30PM on an August evening isn't deafening but it is suspicious. I had just checked the 1800 mile weather radar on weather.com and there's no storm activity within 200 miles of us. No lightning, no thunder, no 'Thump!' of a tree falling or a vehicle hitting a power pole or the bigger 'THUMP!' of an aircraft hitting the ground. Just the light by my chair going out and the fan on the dehumidifier in the kitchen coasting to a stop - and not the usual flicker of power off, on, off, on, off to stay.
Use the Fenix E12 in my pocket to light my way to get the LED head light off the knob of the door to the basement stairs so I'll have hands-free light to make my way through the house - none of the LED nightlights are on without power but the battery-powered motion sensor lights in the hall and on the basement stairs will still work. Try to check the outage map for the electric co-op and there's no internet connectivity from my laptop. I know the Uverse router and the 24 port network switch still have power as I can connect to the Raspberry Pi web server on my home network, which also means all of the network's UPS units are operational. Try the data link on the cell phone and I get a somewhat slow connection but at least some parts of the internet are still there. The co-op's power outage map has the red fill for "More than 350 meters out" on all of their substations. I'll be back to check the percent out at each substation later, as that many outages swamp their outage server and it could be several hours before they have accurate numbers - if that server's backup power lasts long enough. Right now I need to get my "Wait until daylight" backup power system going to power the fridge and a few lights now and the freezer in eight or ten hours if commercial power is still out in the morning.
Where did "Wait until daylight" come from? It's a small solar-charged system that's good for eight to 20 hours depending on the season but it does provide enough power that there's no need for me to be out in a thunderstorm or in the dark at 30F and shoveling my way through seven inches of snow to get a gasoline generator out of the equipment shed. So it's my "Wait until daylight" backup system.
To the basement. Throw the breaker that connects the 2000 watts continuous pure sine wave inverter to the battery bank and turn on the inverter. It does soft-start, ramping its output gradually up to 120 volts AC, so let it get to full output before putting a load on it. Plug a Kill-A-Watt into the inverter so I can monitor the power used, then plug the 12 gauge extension cord into the Kill-A-Watt and run that cord over to the Gen-Tran transfer switch. For now, just power the fridge and some kitchen counter outlets and the LED lights over that counter. Run an extension cord over to the UPS units that keep the network powered so the network has ongoing power and the UPS units can be recharged for future use, if needed. If Uverse is still down in an hour, I'll turn that router off to save a little power (it's "only" 16 watts, but that's 16 watts times 24 hours = 384 watt hours (WH) or 384 / 12 = 32AH from the 12 volt battery bank, plus turn off the DVR for another 20 watts of savings - you do the math for the 24 hour savings). Lots of small loads can make a big difference in the total runtime of the battery backup.
Set a battery-powered alarm clock to wake my wife in the morning. Then put a battery-powered nightlight (actually another Fenix E12 flashlight at its lowest setting and good for 40+ hours on a single alkaline AA cell) in the master bath and turn it on in case she gets up during the night. There's a flashlight on the nightstand by her side of the bed but that's not something she'll think about getting unless she notices that the clocks in the bedroom are dark. Easier to have the E12 as a nightlight in the bathroom and leave the door open a crack.
Get out a grill lighter and put it by the gas cooktop, plus the LED light with magnetic base that can stick to the side of the microwave oven and light the cooking surface below it. There's a hand-crank plus USB rechargeable area light on top of the fridge and it can provide enough light to get out additional lighting for cooking, if needed. Most of the lower cabinets have battery-powered, door-operated LED lighting so anything there is still easily found. There's a two D-cell LED flashlight on the counter for lighting the upper cabinets if needed and that can provide light for a long time.
Write her a note about when power went off and that the fridge has power but she won't have power for the blow dryer, the curling iron, the coffeemaker, the microwave oven or the garage door opener unless I get out a gasoline generator which can handle that much additional load - and she'll have to wake me in time for that if she's planning to go somewhere in the morning. There are no entries for the day on the calendar on the fridge but not everything makes it to that calendar. Get some things out of the pantry for her breakfast and go back to writing my in-progress book. I'm something of a night owl when writing and it could be in the wee hours before I get to bed. The laptop's battery is good for a couple of hours and I can plug it in at one of the kitchen counter outlets if it needs to be recharged before my muse runs out of words.
---
Stopped writing long enough to refill my glass of decaf tea (it's well after midnight, so I don't need caffeine) and used my phone to check Fox and CNN online. All they have to say is "Massive power outage leaves Southeastern US in the dark" and their maps have everything east of the Mississippi River and south of the Kentucky-Tennessee border affected. No reason given for the outage and no mention of prospects for restoration. Not even CNN's news fabricators are saying anything. Isn't that reassuring?
Checked the Uverse connection and no internet, no TV, no landline phone. It failed like that during a snow-caused outage a couple of years ago and it seems they've not improved their backup power capability. Turn off that bit of the network and the UPS that powers it and plan to check it again in an hour or two. At least I can keep the cell phone charged and hope that the nearest cell tower has plenty of backup power. I know the central office that tower connects to has backup: an autostart diesel generator and several weeks of fuel.
Thinking of fuel. We'll be OK if there's enough sun to recharge the battery bank tomorrow but the usual 20 gallons of treated backup fuel is down to about 16 gallons and we'd need something over a gallon a day to run things and charge the battery bank with the inverter generator if there's little or no sun. However, lack of sun is not likely to be a problem in August. I may need to get the rest of the solar panels outside. My solar backup system is mostly a stealth project, with one 250 watt panel set up behind the house where it's almost hidden. If we need maximum solar power for several days, some of the other 1560 watts of solar panels will need to be added depending on the amount of sun and our usage. The Kill-A-Watt on the inverter will tell me how much power we're using, both instantaneous and cumulative, so I'll know how much solar to add or if a gasoline generator is needed - or both. There's also an amp-hour (AH) meter on the feed from the battery bank so I'll know 1) how much the battery bank has been discharged and, from that number, when to shut down the inverter to protect the batteries and 2) how much power has been put back into the batteries by the sun or a generator or both.
Battery voltage is NOT a good indicator of a lead-acid battery's state of charge (SOC) or depth of discharge (DOD), but the actual AH used and restored are an excellent indicator. Charging any battery isn't 100% efficient, with lead-acid charging being an average of 85% efficient over a full charge cycle but that efficiency drops below 60% when 80% charge is reached and below 50% when 90% charge is reached, so the last few percent of a charge can take "forever". Effectively, the battery needs to be charged with 107-115% of the amount it was discharged; in other words, 100AH used will require 107-115AH of replacement depending on the condition of the batteries.
There's nothing wrong with the battery bank, that's just the way the lead-acid chemistry works. There's an online paper on that from C&D Technologies: www.cdtechno.com/pdf/ref/41_2128_0212.pdf
Knowing how much power was removed from the battery bank, I can combine solar plus generator power to ensure that enough power is replaced before sunset - no generators running after dark here except in rare circumstances. I've had more than one five gallon can of gasoline (and kerosene) "disappear" overnight and I certainly don't want that to happen to a generator when commercial AC is out with neither explanation nor expected restoration time.
For those who may think lead-acid batteries are ancient technology and want to know why my battery bank isn't lithium ion or LiFePO4 or maybe LTO, there's a dollars and sense answer. I replaced the previous lead-acid battery bank this year with 420AH of 15 month old AGM batteries that still test as new for $305. I limit the discharge level to 50% (210AH) for maximum battery life. Amazon wants $949 for one 12 volt 100AH Battleborn LiFePO4 battery or about $2000 for almost the same capacity as what I have in AGMs. I don't think that expense makes sense for my purposes, as I can replace the AGMs four more times (or about 20 years' worth) for several hundred dollars less than that and, while the Battleborn has a ten year warranty, they would need to be replaced in less than 20 years. For daily use, the Battleborn's 3,000 charge/discharge cycles would give 8.2 years of cycle life. My AGM batteries would likely only provide 1,000 cycles at the 200AH discharge or 2.73 years of cycle life. That's 33% of the cycle life but at 16% of the cost. The dollars win out in my use for occasional backup power but not for daily primary power. The Battleborn is about half the weight of the AGM (not the "1/3 the weight" often claimed in their ads) which might be important in an RV or boat but not when installed in the basement of a brick house. From my experience with lithium-based batteries in laptop computers, discharging them more than 80% quickly impacts their cycle life so I would only be discharging lithium batteries a maximum of 80% (regardless of the manufacturer's claims that 100% discharge is fine) which means that two 100AH Battleborn batteries would actually provide 160AH of power, which is only 76% of the 210AH the lead-acid AGM batteries provide when only discharged 50%. You need the background information to be able to do the math for YOUR situation when planning backup power. If I used 210AH from the backup system once a week, the lead-acid batteries would theoretically last 19 years. (Do the math: at 1 cycle per week, we get 1000 cycles / 52 weeks = 19.2 years.) However, even well-cared-for AGM batteries (other than the very expensive ones) rarely last more than five to seven years. The ones I replaced were a few months short of 9 years old, so I got much better than average battery life. However, I'm also very careful with my batteries. I replaced the battery in my truck at 5 1/2 years because to my ear the starter was turning a little slow. A year later, that battery is in the basement as a power source for testing inverters and it still tests at greater than 95% capacity. If the new set of AGMs lasts five years, I'll have spent $305 / 60 months = $5.10/month for backup power. If they last nine years, I'll have spent $305 / 108 = $2.84/month. As the ads for other things say, "Just pennies a day". The solar panels and charge controllers are not included in that price as the panels typically have a 25 year life (to 80% of original output) and - barring a lightning strike - the charge controllers are very lightly loaded and should last more than ten years.
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