I think it would be at Reunion Tower in Dallas:
https://en.wikipedia.org/wiki/Reunion_Tower
Jean's father worked on the design of the foundation.
The exterior dome is to be the launch points for the fireworks display. Tower visitors will be surrounded by the fireworks. 360 degrees in the horizontal and probably about 90 degress in the vertical.
https://reuniontower.com/things-to-do/reunion-tower-over-the-top-nye-2019/
Sadly, I can no longer stay awake later than about 8pm.
Tuesday, December 31, 2019
Sunday, December 29, 2019
Public buildings with cylinderical roofs
I just saw another on Texas Country Reporter. In Olfen School near San Angelo and Paint Rock. I'll try to recall/recover the name but it is a construction method from the 1920s-1930s.
My first notice was the Dale School Gym. Also found it used (and documented) at Museum of The Big Bend in Alpine on the Sul Ross campus.
Another of those things that disappeard with Google+.
"Lamella Arch"!
https://photos.app.goo.gl/UHqZFjReQ84PaXxB9
I initially thought building one would need a tremondous amount of scaffolding. I finally found some online information that they are built near the ground, from one side to the other. Raising the under construction side as it progresses.
https://wiki.opensourceecology.org/wiki/Lamella_Roof
My first notice was the Dale School Gym. Also found it used (and documented) at Museum of The Big Bend in Alpine on the Sul Ross campus.
Another of those things that disappeard with Google+.
"Lamella Arch"!
https://photos.app.goo.gl/UHqZFjReQ84PaXxB9
I initially thought building one would need a tremondous amount of scaffolding. I finally found some online information that they are built near the ground, from one side to the other. Raising the under construction side as it progresses.
https://wiki.opensourceecology.org/wiki/Lamella_Roof
Wednesday, December 25, 2019
The COLD Week
The "Cold Week" in December 1983 lives in my memory.
https://www.upi.com/Archives/1983/12/26/Freezing-temperatures-chill-South-citrus-crops-threatened/3097441262800/
Here in Dale, we spent a week below freezing. We were ill equipped. Early in the episode, the exposed grey water drain pipe in the yard froze, preventing sinks from draining. Then, the water supply plumbing under the house froze. We spent days with sinks that wouldn't drain and no water from fawcets. When we manually filled the tank, the toliet continued to flush. The big new tank (earthern "stock" pond) froze; the ice seemed thick enough to walk on. First, I tied a rope around Jean's waist and sent her across, maybe 50'. Then, I tied the rope around my waist. Though I doubt that Jean could have pulled me out; maybe she could have tied her end and I could have pulled myself out. Then, we both walked around on the ice covered water.
After the event, we found all figs had been frozen to the ground; many did not survive. The weakened survivors did not thrive; it took 8-10 years before we again had healthy large fig bushes. Many peach trees had their trunks killed on the north side; some did not survive. The damaged ones were deformed for life. Both the fig and peach damage can be attributed to lack of acclimation; the freeze came before the plants were fully domant.
I believe that was the freeze that killed most citrus in The Valley which percipitated the move to Texas Ruby Red Grapefruit which today dominates the market.
We were heating the house with a wood burning stove (as we have been doing for ~40 years now). The house is on piers and the perimeter was not well sealed. I believe the event stimulated us to put in some storm windows and install a better stove as well as improve the under pinning. I know it stimulated me to install electric heating tape and insulation on the under house plumbing. That heating tape is still there but has never been turned on except to test.
I took the trouble to look up the low and high temperature records for Austin; AFAIK, closer records are not available. Dale was likely a little colder than Austin.
Saturday 12/17/1983 36-45
Sunday 12/18/1983 23-41
Monday 12/19/1983 21-30
Tuesday 12/20/1983 26-36
Wednesday 12/21/1983 23-36
Thursday 12/22/1983 12-26
Friday 12/23/1983 16-30
Saturday 12/24/1983 12-23
Sunday 12/25/1983 10-25
Monday 12/26/1983 14-28
Tuesday 12/27/1983 27-57
Wednesday 12/28/1983 24-39
Thursday 12/29/1983 17-33
Friday 12/30/1983 17-37
Saturday 12/31/1983 19-51
Sunday 1/1/1984 45-60
I count 14 consequetive overnight freezes, about five days below freezing, about nine days without temperatures significantly above freezing.
https://www.upi.com/Archives/1983/12/26/Freezing-temperatures-chill-South-citrus-crops-threatened/3097441262800/
Here in Dale, we spent a week below freezing. We were ill equipped. Early in the episode, the exposed grey water drain pipe in the yard froze, preventing sinks from draining. Then, the water supply plumbing under the house froze. We spent days with sinks that wouldn't drain and no water from fawcets. When we manually filled the tank, the toliet continued to flush. The big new tank (earthern "stock" pond) froze; the ice seemed thick enough to walk on. First, I tied a rope around Jean's waist and sent her across, maybe 50'. Then, I tied the rope around my waist. Though I doubt that Jean could have pulled me out; maybe she could have tied her end and I could have pulled myself out. Then, we both walked around on the ice covered water.
After the event, we found all figs had been frozen to the ground; many did not survive. The weakened survivors did not thrive; it took 8-10 years before we again had healthy large fig bushes. Many peach trees had their trunks killed on the north side; some did not survive. The damaged ones were deformed for life. Both the fig and peach damage can be attributed to lack of acclimation; the freeze came before the plants were fully domant.
I believe that was the freeze that killed most citrus in The Valley which percipitated the move to Texas Ruby Red Grapefruit which today dominates the market.
We were heating the house with a wood burning stove (as we have been doing for ~40 years now). The house is on piers and the perimeter was not well sealed. I believe the event stimulated us to put in some storm windows and install a better stove as well as improve the under pinning. I know it stimulated me to install electric heating tape and insulation on the under house plumbing. That heating tape is still there but has never been turned on except to test.
I took the trouble to look up the low and high temperature records for Austin; AFAIK, closer records are not available. Dale was likely a little colder than Austin.
Saturday 12/17/1983 36-45
Sunday 12/18/1983 23-41
Monday 12/19/1983 21-30
Tuesday 12/20/1983 26-36
Wednesday 12/21/1983 23-36
Thursday 12/22/1983 12-26
Friday 12/23/1983 16-30
Saturday 12/24/1983 12-23
Sunday 12/25/1983 10-25
Monday 12/26/1983 14-28
Tuesday 12/27/1983 27-57
Wednesday 12/28/1983 24-39
Thursday 12/29/1983 17-33
Friday 12/30/1983 17-37
Saturday 12/31/1983 19-51
Sunday 1/1/1984 45-60
I count 14 consequetive overnight freezes, about five days below freezing, about nine days without temperatures significantly above freezing.
Sunday, December 22, 2019
Faster Horses
https://www.youtube.com/watch?v=vnvMcX95G20
On reflection and PV install experience, I will add "Bigger Wire".
On reflection and PV install experience, I will add "Bigger Wire".
Thursday, December 19, 2019
Last electric bill for 2019
$-157.20 which brings known credit for the year to $-744.74. The ~$500 transformer upgrade, a few months ago, was paid out of the credit. I say "known credit" because a yet unkown credit of ~$1500 should appear sometime after year end. Stay tuned.
I am on track to average $-200+ per month with currently installed PV equipment. I continue to plan, scheme, and install so my goal is for about $-400/month a year from now.
The really great deals we have enjoyed on Enphase M215 microinverters for the past year or longer have disappeared. I am very seriously looking at some even better deals on string inverters. M215s with cabling were costing around $50/panel; the string inverters may cost as little as $15/panel. The string inverters, however, are less versitile and less safe.
1/24/2020
In anticipation of the year end credit, I have reviewed the bill for February 2019.
No dates are given for the credits. The bill is dated 2/16/2019 for service over the period 1/15/19 through 2/12/19. Credits are as follows:
Meter 1 1992 kwh $80.85
Meter 2 5503 kwh $223.05
Meter 3 2182 kwh $87.85 $391.75 total
I am on track to average $-200+ per month with currently installed PV equipment. I continue to plan, scheme, and install so my goal is for about $-400/month a year from now.
The really great deals we have enjoyed on Enphase M215 microinverters for the past year or longer have disappeared. I am very seriously looking at some even better deals on string inverters. M215s with cabling were costing around $50/panel; the string inverters may cost as little as $15/panel. The string inverters, however, are less versitile and less safe.
1/24/2020
In anticipation of the year end credit, I have reviewed the bill for February 2019.
No dates are given for the credits. The bill is dated 2/16/2019 for service over the period 1/15/19 through 2/12/19. Credits are as follows:
Meter 1 1992 kwh $80.85
Meter 2 5503 kwh $223.05
Meter 3 2182 kwh $87.85 $391.75 total
Tuesday, December 17, 2019
Pleasant Grove School near Texarkana
It is in the news because of the football team.
https://www.pghawks.com/teams/?u=PGHAWKSATHLETICS&s=org
The school district has become quite affluent as the area moved from agriculture to mostly low density suburban.
I went to 1st grade at Pleasant Grove on Kings Highway, about 1950; there was a single elementary school. It was a frame building with, as I recall, three rooms. In the center was a smallish meeting room like a small auditorium. On each side were class rooms, one for lower grades, one for higher. Something like grades 1 to 3 and grades 4 to 6; two teachers taught all six classes. There was a large playground adjacent to the building with outhouses more distant. No indoor plumbing. I believe the school was on a fairly large tract; the school district seems to have remained centered on the property.
I remember a night time meeting at the school for teachers and parents. Some rowdies threw a dead skunk or skunk scent glands into the meeting and disrupted it.
I also remember drinking from a stream near the outhouses. On a dare. It was murky water; not very clean looking. Perhaps that contributed to my semi-robust constitution.
My mother and her siblings, in the 1920s-30s, went to schools in Texarkana several miles from the Moores Lane homesite. Pleasant Grove is a couple of miles in the other direction.
I recall a "convience store"/ gas station across the road from the school. There, you could buy your RC Cola and the peanuts to put in it.
Apparently, Pleasant Grove has come a long way. It evolved from a single school into a well funded multi-campus school district.
https://www.pgisd.net/
This is all I was able to google up on history:
https://en.wikipedia.org/wiki/Pleasant_Grove_Independent_School_District_(Bowie_County,_Texas)
https://www.pghawks.com/teams/?u=PGHAWKSATHLETICS&s=org
The school district has become quite affluent as the area moved from agriculture to mostly low density suburban.
I went to 1st grade at Pleasant Grove on Kings Highway, about 1950; there was a single elementary school. It was a frame building with, as I recall, three rooms. In the center was a smallish meeting room like a small auditorium. On each side were class rooms, one for lower grades, one for higher. Something like grades 1 to 3 and grades 4 to 6; two teachers taught all six classes. There was a large playground adjacent to the building with outhouses more distant. No indoor plumbing. I believe the school was on a fairly large tract; the school district seems to have remained centered on the property.
I remember a night time meeting at the school for teachers and parents. Some rowdies threw a dead skunk or skunk scent glands into the meeting and disrupted it.
I also remember drinking from a stream near the outhouses. On a dare. It was murky water; not very clean looking. Perhaps that contributed to my semi-robust constitution.
My mother and her siblings, in the 1920s-30s, went to schools in Texarkana several miles from the Moores Lane homesite. Pleasant Grove is a couple of miles in the other direction.
I recall a "convience store"/ gas station across the road from the school. There, you could buy your RC Cola and the peanuts to put in it.
Apparently, Pleasant Grove has come a long way. It evolved from a single school into a well funded multi-campus school district.
https://www.pgisd.net/
This is all I was able to google up on history:
https://en.wikipedia.org/wiki/Pleasant_Grove_Independent_School_District_(Bowie_County,_Texas)
Wednesday, December 4, 2019
To Utah
I took a few photos in Paint Rock, home to Rick Perry. Many old and attractive buildings. Apparently county seat of Concho County. On the Concho River. Downstream from San Angelo? Paint Rock rivals Mentone for the smallest county seat in Texas.
https://photos.app.goo.gl/7FFYBazUqUYHKrMh7
https://photos.app.goo.gl/7FFYBazUqUYHKrMh7
Just past the historic town of Gail (Borden County), I encountered a huge solar farm under construction. Hundreds of acres. Earth work in progress enormous stocks of material stacked around the edges. One photo can not present the entire site. 10-15 miles farther, on the edge of LaMesa, there was another large completed installation which was not yet on Google "satellite" view. Fairly old since weeds needed mowing. A one axis tracking system. Panels pivoted on long rails. It looked cheap and cost effective.
I realized that LaMesa (la meesa) was so named because it is on top of the Cap Rock a few miles from the edge. The PV site under development is on poor land below the Cap Rock while the completed site is above. Multi use on the land: there is one photo of a blade assembly ready for lifting into place on a wind generator. There are many wind generators along the edge of the Cap Rock. Now, the PV, some very near the wind. And a little bit of oil. Above the Cap Rock, soil is quite good; with well water, it is intensively farmed.
https://en.wikipedia.org/wiki/Gail_Borden
Albuquerque and Gallop
https://photos.app.goo.gl/np3Y1dN9rJAof2aeA
The most valuable car in the Unser Museum is the Novi. Worth about $3mil, One of two and no one knows the whereabouts of the other. Photos 4, 5, and 6.
Last photo is a plate of chilles rellenos at Jerry's Cafe in Gallop.
At the Albuquerque SuperCharger, three of six nozzles had been vandalized and were not usable. I did not have to wait and got near 140kw. By the time I left there were three in line.
At the Gallup SuperCharger, one of the four stations did not work. Two others gave about 80kw. The "good" one gave me a good rate in the afternoon but was very slow the next morning; it took me more than an hour to get from ~80% to near 100%. Starting about 30kw and dwindling painfully to nothing. No waiting there.
Page and Kanab
Slow charging at Gallop. Did not have breakfast at Jerry's as intended.
https://en.wikipedia.org/wiki/Kayenta_Mine
I passed near the above mine and had to wikipedia it up to find out about it. The highway passed under a very long conveyor that dumped into a very large and tall silo. An electric rail line followed the highway for many miles away from the silo. I had hoped to see an electric train operating from the overhead wires. I finally noticed the overhead wiring was in disrepair. Mr Peabody did not complete hauling away the mountain. Here is the silo and the conveyor crossing highway 180:
https://goo.gl/maps/ZG9YshKqi1FCEtdr8
Here is the power plant end of the rail line:
https://goo.gl/maps/yuCW1fCiGDVGbGy99
I followed it a relatively short distance of ~5 miles along side the highway. I'm guessing the total distance of the electric rail line might be about 50 miles. I saw the power plant near Page but did not realize it was the one serviced by the Peabody mine.
Here is the wiki article on the electric railroad that caught my attention:
https://en.wikipedia.org/wiki/Black_Mesa_and_Lake_Powell_Railroad
Then, off in the distance, a big mountain dominated the area. I found it is "Navajo Mountain". Much higher than anything within 50-100 miles. I had thoughts of finding my way to the top on some subsequent trip. Apparently that is not to be:
https://en.wikipedia.org/wiki/Navajo_Mountain,_Utah
https://www.summitpost.org/navajo-mountain-ut/397784
Kanab and Byrce Canyon
https://photos.app.goo.gl/itrPm8XJ7wdQ154n8
Very little snow in Kanab at 5k-6k feet. At Bryce, 8k+ feet, like 2' of snow. Weather was good, though. After that climb, I was apprehensive about the energy used and charged a bit at Ruby's very nice complex at the entrance to the park (photos posted). They have Tesla charging and do not care who uses. They are unacknowledged by Tesla; I found them on PlugShare. I failed to find a place listed by Tesla after squandering 15 miles looking (in Tropic). Tropic is the site of a very early (~1895) Mormon water diversion project.
https://www.nps.gov/brca/learn/historyculture/pioneerstory.htm
http://www.townoftropicut.gov/town-history.htm
Only me and one other at the Days Inn in Kanab; I didn't see the other at breakfast. VERY nice. VERY quiet. Only about $60 down from ~$110 during the summer. AND, I'm charging about $5 worth per day. Many Kanab hotels are closed for the winter. When I expressed concern for their low business volume, they reassured me that they have two bus loads of Korean tourists coming in a couple of days.
Zion, Lake Mead, Williams
https://photos.app.goo.gl/cv9QZsXhKK6aDzfa9
Photos include my bowl of green chile stew with corn bread.
Sierrra Blanca, Brashear, Dale
I just couldn't do a trip without inserting a minor death march. A bit more than 900 miles in about 20 hours. That's with an hour or more in Brashear loading up and talking about string inverters.
Home. No water. No heat. Temperature about 35 deg. All easily fixable.
I realized that LaMesa (la meesa) was so named because it is on top of the Cap Rock a few miles from the edge. The PV site under development is on poor land below the Cap Rock while the completed site is above. Multi use on the land: there is one photo of a blade assembly ready for lifting into place on a wind generator. There are many wind generators along the edge of the Cap Rock. Now, the PV, some very near the wind. And a little bit of oil. Above the Cap Rock, soil is quite good; with well water, it is intensively farmed.
https://en.wikipedia.org/wiki/Gail_Borden
Albuquerque and Gallop
https://photos.app.goo.gl/np3Y1dN9rJAof2aeA
The most valuable car in the Unser Museum is the Novi. Worth about $3mil, One of two and no one knows the whereabouts of the other. Photos 4, 5, and 6.
Last photo is a plate of chilles rellenos at Jerry's Cafe in Gallop.
At the Albuquerque SuperCharger, three of six nozzles had been vandalized and were not usable. I did not have to wait and got near 140kw. By the time I left there were three in line.
At the Gallup SuperCharger, one of the four stations did not work. Two others gave about 80kw. The "good" one gave me a good rate in the afternoon but was very slow the next morning; it took me more than an hour to get from ~80% to near 100%. Starting about 30kw and dwindling painfully to nothing. No waiting there.
Page and Kanab
Slow charging at Gallop. Did not have breakfast at Jerry's as intended.
https://en.wikipedia.org/wiki/Kayenta_Mine
I passed near the above mine and had to wikipedia it up to find out about it. The highway passed under a very long conveyor that dumped into a very large and tall silo. An electric rail line followed the highway for many miles away from the silo. I had hoped to see an electric train operating from the overhead wires. I finally noticed the overhead wiring was in disrepair. Mr Peabody did not complete hauling away the mountain. Here is the silo and the conveyor crossing highway 180:
https://goo.gl/maps/ZG9YshKqi1FCEtdr8
Here is the power plant end of the rail line:
https://goo.gl/maps/yuCW1fCiGDVGbGy99
I followed it a relatively short distance of ~5 miles along side the highway. I'm guessing the total distance of the electric rail line might be about 50 miles. I saw the power plant near Page but did not realize it was the one serviced by the Peabody mine.
Here is the wiki article on the electric railroad that caught my attention:
https://en.wikipedia.org/wiki/Black_Mesa_and_Lake_Powell_Railroad
Then, off in the distance, a big mountain dominated the area. I found it is "Navajo Mountain". Much higher than anything within 50-100 miles. I had thoughts of finding my way to the top on some subsequent trip. Apparently that is not to be:
https://en.wikipedia.org/wiki/Navajo_Mountain,_Utah
https://www.summitpost.org/navajo-mountain-ut/397784
Kanab and Byrce Canyon
https://photos.app.goo.gl/itrPm8XJ7wdQ154n8
Very little snow in Kanab at 5k-6k feet. At Bryce, 8k+ feet, like 2' of snow. Weather was good, though. After that climb, I was apprehensive about the energy used and charged a bit at Ruby's very nice complex at the entrance to the park (photos posted). They have Tesla charging and do not care who uses. They are unacknowledged by Tesla; I found them on PlugShare. I failed to find a place listed by Tesla after squandering 15 miles looking (in Tropic). Tropic is the site of a very early (~1895) Mormon water diversion project.
https://www.nps.gov/brca/learn/historyculture/pioneerstory.htm
http://www.townoftropicut.gov/town-history.htm
Only me and one other at the Days Inn in Kanab; I didn't see the other at breakfast. VERY nice. VERY quiet. Only about $60 down from ~$110 during the summer. AND, I'm charging about $5 worth per day. Many Kanab hotels are closed for the winter. When I expressed concern for their low business volume, they reassured me that they have two bus loads of Korean tourists coming in a couple of days.
Zion, Lake Mead, Williams
https://photos.app.goo.gl/cv9QZsXhKK6aDzfa9
There are a couple of photos of animal routing fencing. In Canada, I saw similar fences targeted to deer, elk, etc. But the Lake Mead fences are about 18" high. In Texas, I might suspect they are trying to keep armadillos off the road and directed to culverts. Here, I suspect tortoises.
Williams, South Rim, Gallup
https://photos.app.goo.gl/emAfR4QPLKtWiehs7
https://photos.app.goo.gl/tDwFkkPdM17yELjYWilliams, South Rim, Gallup
https://photos.app.goo.gl/emAfR4QPLKtWiehs7
Photos include my bowl of green chile stew with corn bread.
Sierrra Blanca, Brashear, Dale
I just couldn't do a trip without inserting a minor death march. A bit more than 900 miles in about 20 hours. That's with an hour or more in Brashear loading up and talking about string inverters.
Home. No water. No heat. Temperature about 35 deg. All easily fixable.
Sunday, December 1, 2019
PowerWall agumentation, new layout
https://photos.app.goo.gl/1wHoSgrKHEsAT3n66
Last photo of wall mounted components:
1) Upper left: two 250w grid tie micro inverters as intended for 60 cell PV panels.
2) Upper right: two "500w" 12vdc grid tie inverters.
3) Lower center: 12vdc to 36 vdc converter.
4) Lower right: 240vac recepticles used to accept power.
Several possible configurations, some could be concurrent:
1) 36vdc from batteries into either one or two 250w micro inverters. Batteries from hoverboards repurposed to power golf carts are shown in first two photos. Up to about 80 4ah hoverboard batteries are on hand to be paralleled. About 12 kwh of available energy.
2) 36vdc from the 12v to 36v converter powered from a car into either one or two 250w micro inverters.
3) 12vdc inverter powered from a car.
In my case, "car" could be one of two Mitsubshi imievs or a Tesla Model 3.
With either type of car, the 12vdc can be up to about 1kw and depletes the car's main battery through the car's DC-DC which converters main battery voltage to about 14vdc.
For my purposes, 500 watts of augmentation is more than sufficient so no more than two micro inverters need be used. Though several more could be easily configured. The MC4 splitters photographed have space for one more inverter;
power outputs can easily be daisy chained together.
The 12vdc inverters are undesirable because of low efficiency; they produce only about 200 watts each and that not efficiently. Producing ~400 watts overnight nearly depletes an imiev 16kwh battery. Energy supplied at 240vac would be only about 6kwh. The micro inverters are 95%+ efficient.
I have a single PowerWall which can supply 10-12 kwh at up to 5kw. The battery size is marginal for using night time air conditioning during the summer. Cloudy days can result in not full PW charges at dusk. Either condition can make augmentation desirable.
I have about 112 kwh of energy available from four sources: 12 kwh from hoverboard batteries, 70kwh from the Tesla, 15kwh from each of two imievs. Efficiency from the hoverboard batteries is very good, 95%+. Efficiency of cars into the 12vdc inverter is poor, perhaps as low as 50%. Efficiency going through the 12vdc -> 36vdc converter (car -> converter -> microinverters) is yet to be undetermined. With some additions and reconfiguring, peak powers could reach 3-4kw. Starting with fully charged batteries, I have hope of getting through about a week with no grid and no sunlight. The single battery PowerWall will do 5kw with ~12kwh stored. The PowerWall supplies power as demanded; the augmentation supplies fixed power. The fixed power augmentation typically goes into demand. If demand is insufficient, the augmentation power is either sold to grid or charges the PW battery. In order to avoid sales to grid, with my current PW set up, I must go off grid.
See previous augmentation discussion:
https://wmckemie.blogspot.com/2019/09/micro-grid-and-augmentation.html
1/15/2020
A series of very cloudy days, leaving me starting some nights with ~50% PW charges, have encouraged me to do some more testing.
1) The 36v golf cart battery -> one or two microinverters -> house 240vac continues to work very well. One inverter gives a solid continious ~230 watts; two inverters gives twice that.
2) 12vdc from an EV -> 12vdc/36vdc "upverter" -> microinverters works less well. Output power varies quite a bit from the expected to near zero. Average is about half that expected. This is almost certainly a microinverter power tracking problem that I do not yet have a solution to. Perhaps I'll find a high efficiency gridtie microinverter without power tracking to test. Suggestions solicited.
3) 12vdc from an EV -> 12v cheap chinese inverter -> house 240vac has not recently been tested due to previous inefficiency.
Last photo of wall mounted components:
1) Upper left: two 250w grid tie micro inverters as intended for 60 cell PV panels.
2) Upper right: two "500w" 12vdc grid tie inverters.
3) Lower center: 12vdc to 36 vdc converter.
4) Lower right: 240vac recepticles used to accept power.
Several possible configurations, some could be concurrent:
1) 36vdc from batteries into either one or two 250w micro inverters. Batteries from hoverboards repurposed to power golf carts are shown in first two photos. Up to about 80 4ah hoverboard batteries are on hand to be paralleled. About 12 kwh of available energy.
2) 36vdc from the 12v to 36v converter powered from a car into either one or two 250w micro inverters.
3) 12vdc inverter powered from a car.
In my case, "car" could be one of two Mitsubshi imievs or a Tesla Model 3.
With either type of car, the 12vdc can be up to about 1kw and depletes the car's main battery through the car's DC-DC which converters main battery voltage to about 14vdc.
For my purposes, 500 watts of augmentation is more than sufficient so no more than two micro inverters need be used. Though several more could be easily configured. The MC4 splitters photographed have space for one more inverter;
power outputs can easily be daisy chained together.
The 12vdc inverters are undesirable because of low efficiency; they produce only about 200 watts each and that not efficiently. Producing ~400 watts overnight nearly depletes an imiev 16kwh battery. Energy supplied at 240vac would be only about 6kwh. The micro inverters are 95%+ efficient.
I have a single PowerWall which can supply 10-12 kwh at up to 5kw. The battery size is marginal for using night time air conditioning during the summer. Cloudy days can result in not full PW charges at dusk. Either condition can make augmentation desirable.
I have about 112 kwh of energy available from four sources: 12 kwh from hoverboard batteries, 70kwh from the Tesla, 15kwh from each of two imievs. Efficiency from the hoverboard batteries is very good, 95%+. Efficiency of cars into the 12vdc inverter is poor, perhaps as low as 50%. Efficiency going through the 12vdc -> 36vdc converter (car -> converter -> microinverters) is yet to be undetermined. With some additions and reconfiguring, peak powers could reach 3-4kw. Starting with fully charged batteries, I have hope of getting through about a week with no grid and no sunlight. The single battery PowerWall will do 5kw with ~12kwh stored. The PowerWall supplies power as demanded; the augmentation supplies fixed power. The fixed power augmentation typically goes into demand. If demand is insufficient, the augmentation power is either sold to grid or charges the PW battery. In order to avoid sales to grid, with my current PW set up, I must go off grid.
See previous augmentation discussion:
https://wmckemie.blogspot.com/2019/09/micro-grid-and-augmentation.html
1/15/2020
A series of very cloudy days, leaving me starting some nights with ~50% PW charges, have encouraged me to do some more testing.
1) The 36v golf cart battery -> one or two microinverters -> house 240vac continues to work very well. One inverter gives a solid continious ~230 watts; two inverters gives twice that.
2) 12vdc from an EV -> 12vdc/36vdc "upverter" -> microinverters works less well. Output power varies quite a bit from the expected to near zero. Average is about half that expected. This is almost certainly a microinverter power tracking problem that I do not yet have a solution to. Perhaps I'll find a high efficiency gridtie microinverter without power tracking to test. Suggestions solicited.
3) 12vdc from an EV -> 12v cheap chinese inverter -> house 240vac has not recently been tested due to previous inefficiency.
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