1500 Acres of PV near Jeddo

 The road corner photo I first believed to be the site of the 1500 acres project.  A major power line crosses a corner of the site.  High line tower is in one photo.  So far, I estimate the cleared area to be about 200 acres.  The site is about 4 miles south of Rosanky (on Jeddo Road) and about 6 miles north of Jeddo.   

https://goo.gl/maps/PKqmHHMywRgGXmKX7

I imagine the full site is all of the approximately square mostly pasture land including a home/ranch site in the middle.  I am not able to see the high voltage line in the aerial photo; perhaps the line is newer than the photo.

https://photos.app.goo.gl/ENfydvh1cy3W7s3g9

Signage indicates much local opposition to the project.  The opposition seems to be from mostly smaller parcel owners.  None of the big fancy places have signs posted.  URL on the signs:

http://rosankytexas.com

The maps there tell us the project goes north to near Rosanky, all east of Jeddo Road, all north of Cistern Road.  The project is to surround a notable feature on Jeddo Road near Rosanky; a Flint Hills terminal of some sort.

This is my revised estimate of the site location:

https://goo.gl/maps/h7cjC9PF5bUtatv59

Flint Hills is the white area on the east side of Jeddo Road near Rosanky. 

The opposition site indicates that the customer for the project's power is Austin Energy.

I found only one building, pictured, that looks like it might have been part of the town of Jeddo; the building could be a school house.  About a quarter mile north of the building is the pictured Jeddo Cemetery.

Picture is the main entrance to  D&D Ranch which is perhaps the largest parcel in the area.  Many years ago, I sold some peas to the D&D manager.  Someone approached me at a farmers market, either Bastrop or Smithville, and asked about a volume pea purchase.  I eventually delivered several, perhaps eight, bushels through that gate.  As I recall they wanted unshelled peas though I offered shelled in bags.  The story was that they wanted them to serve to guests/customers.  They, at least at that time, were in the exotic game business.  Driving by those lakes (you can steer to from on the aerial photos), I concluded that the lakes were filled from wells.  A very expensive proposition.  The whole place was impressively manicured.

In another photo are some obviously maintained low shrubs in clumps around native trees.  I suspect maintained as bird habitat.

11/6/2022

I went by the site again yesterday for the first time since the original post.  It is not exactly where expected but the site is now obvious with much earth work going on.  There are two construction entrances on two county roads several miles apart.

 Earlier, it was not clear that the project would actually happen.  Now, it seems a certainty.

The "rosankytexas" site, URL above, has been posting updates on the project.

Grid Down Home Power

 Work in progress.  Options ordered in increasing cost:

1) There are MANY examples of extracting 120vac power from the 12vdc battery of a car.  This is a very good one:

http://aprs.org/FD-Prius-Power.html

Best choices of 12v power would be either a hybrid such as Prius or Volt or a real EV including Tesla, Leaf, Bolt, etc.  The hybrids have the advantage (or disadvantage) of charging from the car's engine. 

I believe 12v powers should be limited to about 2kw.

2) Small engine driven generator.  I think the 12v car battery is cheaper.  Not a good solution because of engine maintenance, noise, fuel.

3) MPP with PV panels.  I hope others will supply more data for this one.  There are a number of such "hybrid inverters" out there.  In my opinion, grid tie is required in order to justify the cost.  Other suppliers are SolArk and Growatt  MPP has a good reputation.

https://usamppsolar.com/

I think two friends might be successfully using this MPP:

 https://www.ebay.com/itm/2400W-Hybrid-Inverter-Build-in-50A-PWM-Solar-Controller-Regulator-DC24V-AC-110V/353254176496?hash=item523f96f6f0:g:wu0AAOSwv11faHAc

About $350.  Requires a 24v battery and low voltage PV string.

 I expect a full house 240vac split phase will require two MPP inverters and either one or two 48vdc batteries as well as the needed PV panels.   An advantage (and disadvantage) is that all major components (inverter (both grid tie and islanding) and battery charger) is incorporated and integrated in one unit.  A much smaller and less expensive system can be configured to supply 120vac only.

Maybe someone will supply costs for both a minimal 120vac, 2kw system and a full 240vac ~5kw system.

4) Whole house 5+kw engine driven generator from Generac or other

https://www.generac.com/

Cost is likely to be $5k+.   Engine problems of 2).  Preferred fuel would likely be propane.

5) Whole house PV with battery back up.  Though there are others, IMHO Tesla PowerWall is the Cadillac.  Cost about $13k minimum plus PV.

 https://wmckemie.blogspot.com/2021/01/testing-powerwall-off-grid.html

In looking at the MPP systems in 3), I see one great advantage of a PW is the PV versatility.   One can use any combination of grid tie inverters and panel strings.

Dale Citrus

 

I was only recently told of this orange tree in downtown Dale.  I never before noticed it.  I've driven past thousands of times.  It is on the south side of a house but it looks like the house provides minimal protection.  I estimate around 30 years old and no evidence of freeze damage. Then, after taking the photo, I noticed another younger tree about 1/2 mile north of Dale.

https://photos.app.goo.gl/XStCynBbg56xFMsQ6

The photos in the above album are zoomable for more detail.  The photo in this post is not.

I haven't talked to the owner of the rather spectacular orange tree pictured.  I will eventually.  Likely, he knows nothing of the variety.  I would like to learn if that tree was planted before or after our 1980s freezes.

A few weeks ago, my doctor was putting demands on me to get prescription renewals that I found excessive.  I drove to The Valley and bought the needed drugs on the other side of the border.  But, that is another story.  I stopped in a citrus nursery near Edinburg, where no English was spoken, and bought three poorly labeled citrus plants.  I'm near certain that the varieties are good for The Valley and not likely for central Texas.  I could be wrong since much Valley citrus was wiped out by a freeze in the 1980s and they might be tending toward some frost tolerance.  There are a few well known varieties that will go down around 25 deg.  Meyer lemon and Satsuma tangerine are examples.  Generally those varieties do not make good, market acceptable, fruit.  I've planted citrus here in the past that has failed to survive.   The area south of New Orleans is a semi-local area where citrus is successfully commercially grown; though The Valley is larger and better known.  I'll plant at least one of the new plants; that'll likely be my last citrus attempt.  Right now, the plants are being protected in a neighbor's greenhouse. 

A new report on downtown Dale orange tree.  The guy's name is "Brite", a common name in Dale.  He has lived in the house about 20 years and the trees (there are two growing together) started when his daughters spit out orange seeds in the area.  Not intentionally planted.  So, the variety is unknown and not likely the same as the originating fruit.  Like other fruit trees, citrus is grafted to give predictable fruit.  He said the foliage was often frozen off the the wood survived.  That is, leaves always sprouted from the old wood.  He gave me three fruit; the first one sampled was very good, very much like commercial fruit.

2/27/2021

I added a photo of the downtown Dale orange tree after our "big freeze".  Temperature down to 5-10 deg and below freezing for more than 140 continuous hours.  At this point, the tree doesn't look too bad.  All brown, of course.  It may well have been killed to the ground.  Only time will tell.

Testing PowerWall off grid

The test is now complete.  I ran from about 5pm Tuesday 2/19/2021 continuously through about 10:30am Monday 2/25/2021 with the grid disconnected.  It was a highly successful test.  I'll put a synopsis here and leave the "stream of consciousness" stuff below for you to decipher if you wish.

The questions that needed answers are:

1) What happens if PV power can not be accommodated by local demand including PW charging? 

My PV production can reach about 25kw while the PW charging can accept only 5kw.  The short answer is that the PW shifts the frequency off of the standard 60hz and all inverters are expected to respond by suspending production.  That happens and the PV quickly shuts down and the PW can continue to supply less than 5kw of local demand from the PW battery.   The PW and PV can get into a cycle of PV being shut down and restarting 5 minutes later only to be immediately shut again.  Things go more smoothly if PV capacity is reduced to approximate the PW capacity to charge.

2) What happens if local demand exceeds the 5kw power capacity of the PW?

The PW shuts down and stops supplying local demand.  This should be avoided for several reasons.  One is that, due to inverters shutting down, the power will be down for about five minutes.  Another is that many devices such as clocks will have to be reset.  Another is that monitoring stops working and it is difficult to figure out what is going wrong or has gone wrong.  One fix for this is to adjust demands.  For instance, I have to watch the operation of my 5kw water heater closely to be sure that there are no other significant loads a the same time.

3) What happens when you try to charge a car?

Obviously car charging should be avoided unless there is good PV production.  It is risky to attempt to charge above the 5kw limit of a single battery PW.  However, up to 5kw charging is entirely feasible if one closely monitors other significant local loads.  I have a nattering nabob friend who has declared that car charging could not be done from a PW while off grid.  He is incorrect.  But, loads  such as a water heater must be managed to avoid conflicting with car charging.  PV production may be highly variable so it is best to insure that the PW battery can supply the loads if PV power disappears unexpectedly.  While experimenting charging my Tesla, I was surprised to find that Tesla has fairly recently integrated PW and Tesla car software to force the car to slow charging when it appears the PW may fail to supply demand.  I have more testing and study to do on that feature. 

The problems cited all become much easier if a PW has a generous number of battery units.  Each battery unit adds 5kw of supply capacity and 5kw of variable PW charging demand.

I did not address the possible problem of the PW battery becoming depleted.  If it does become depleted, one may well be left with no electric power whatsoever. for an indefinite time.  Once down and without grid power the PW will take 5 minutes to get the PV started again.  During that time, the PW will have to be supplying local demands even with good sun.  I imagine the PW has some reserve capacity which might be used for restarting especially if grid power can handle local loads immediately.

 Older parts of posting:

 I've had the PowerWall for about two years now and not done much testing in preparation of a long term grid down situation.  The reason is that I've been reluctant to lose the revenue from PV energy sales to my utility.  In fairly good production weather, that is around $10/day.  Sometimes near $20.

Due to a friend's questioning of off grid PW use during cloudy weather, I've decided to do a multi day test while we have a long period of overcast weather in the forecast.  The low production overcast weather will minimize the lost revenue as well as reduce the problem of the PW being unable to handle high PV production.  I switched off grid about dusk on Tuesday 2/19/2021.  The PW had a state of charge of about 95%.  This very cloudy morning, Wednesday 2/20/2021, the SOC bottomed out 25% about 9am.  At about 9:30, even though it is very cloudy, the PW is charging at about 2.5kw.  Since the charge power limit of my single battery PW is 5kw, something interesting will happen when my PV production goes above the ability of the PW ability to accept.  That is either 5kw or zero depending on whether the PW battery is charged or not.

In good weather while grid connected, I can sell large amounts of PV power to my utility.  Off grid, the PW is unable to deal with PV power above about 5kw; zero if the PW battery is fully charged.  Now, about 10am, the PW charge power is around 3.5kw and I can see trouble coming.   I'll first observe if the PW is able to shut down PV inverters when power is too high.  The PW attempts the shutdown by shifting the "islanding" frequency off of 60hz.

Yesterday, a very cloudy and grid connected day, I produced about 32kwh and sold the utility 26kwh.  There must be some measurement error there because the difference should be about 20kwh.  About  10-12kwh to charge the PW and about 10kwh for daytime house consumption.

 11am 2/20/2021.  Still very cloudy but production has been very near 5kw.  I first turned off the 5kw roof top which faces south and produces well for only about 4 mid day hours.  Then turned off another major production block  leaving my most recent projects which are mostly E+W facing and produces 8-9 hours.  PW is at 68% and charging at less than 3kw.  My hope is to get to about 4-5pm with a PW battery that is near 100%.  If that comes to pass, I'll likely leave only that production block on for tomorrow.  Then, tomorrow about noon, evaluate to see if I want to turn more PV back on to get charged by the end of the day tomorrow.

 4pm 2/20/2021.  About 22 hours into the test, things are going VERY well.  I babied it past the water heating but, since then, no worries whatsoever.  The PW became fully charged about 1pm so the PW has been turning PV off regularly.  The PV goes down quickly and gracefully.  After going down, it takes about 5 minutes for inverters to come back up.  The PW is maintaining about 98% charge.  The PV comes on briefly and goes up to above 2kw every 5-6 minutes.

7am 2/22/2021.  Since there is sun in today's forecast, this test is near it's end.  I've been off grid for two days and three nights.  The test is a near total success.  Here are some takeaways:

1) With a single battery PW, I will likely run out of energy if we have two days in succession that are FAR more overcast than the very cloudy weather we've recently had.  My estimate is that that is perhaps a once a year occurrence.

2) By frequency shifting, the PW very quickly and gracefully shuts down PV when needed.  That is, when PV power overwhelms the local demand including the possible 5kw  battery charging.  Even in this cloudy weather, battery charging is generally complete by about noon so the PW cycles PV on and off all afternoon.  During typical sunny weather, my full PV system supplies far more than the 5kw that can be used for PW charging.  Under those conditions, the PW would cycle PV on and off all during the day.

3) A problem is that it takes the PV inverters about 5 minutes to recover or come back on after a shut down.  That means that local demand can not exceed the 5kw PW supply limit during those 5 minute periods. 

4) The consequence of the PW being asked for more power than it can supply is PW shutdown.  Which leaves the house without power for a few minutes until the PW attempts to restart.  When the PW shuts down, the observer becomes blind.  He can not tell what the PW is doing; he can not tell what the PV is doing.

5) During the test, I avoided PW shutdowns.  But just barely.  My 5kw water heater operated during battery charged period so PV was being turned on and off every ~5 minutes.  Early in the day, when the PW was charging, the battery provided a buffer of available power.  That is, during the battery charge period more than 5kw loads can be accommodated.  That might be water heating or car charging.

6) For the test, I did not attempt to make use of the additional power available during the battery charging period.

7) Should we experience a long term grid outage in the near term, I would first lower my water heater demand well below 5kw which would remove the threat of PW shutdown due to high demand.  For the longer term, I plan to add either one or two PW batteries; that would increase my available PW power from 5kw to 10kw or 15kw.

8) I don't know whether the frequent cycling of PV inverters is damaging to the inverters.  In case it is, I would likely turn off large sections of my PV during a long term grid down.  That would both reduce the number of inverters being cycled and reduce the period of the cycling.  Better matching PV capacity to the demand.

9) I should mention that I have changed two demands for the test.  Normally, when grid connected, I allow 36v golf cart charging and 48v lawn mower charging during day light hours.  Neither was used during the test.  I do not normally charge cars at the house since the cost is much lower at another of my meters.  Each of the chargers is 1-1.5kw which does not threaten the off grid 5kw limit.  But, power demand would be too high with either charger plus the water heater.  So, I would likely set my charger timers to morning hours or other to not allow water heating at the same time.

4pm, Saturday 01/23/2021.  I thought I could stop.  But, I just can't.  Test still running.  Yesterday was pretty sunny and I decided to see how the PW behaved with full PV cranking.  Starting about noon, after the PW was fully charged, and about once an hour during high production, the PW shut down leaving me without power.   I watched carefully to see if I should turn off some PV.  But, it behaved fairly gracefully, taking 5-10 minutes each time to get back to normal.  So, I am adding 10) and will continue test at least until Sunday morning.  That will be 5 days and 6 nights by my reckoning.  On second thought, I think I'll do a little car charging tomorrow before going back on grid.  I have a nattering nabob full of shit friend who has opined that a PW could not be used for car charging while off grid.

10) With 20+kw of PV power, the PW can fail to get PV shut down promptly enough.  Leaving the house without power for a few minutes.  So, during real long term grid outages with my 5kw PW, I will have to disconnect some PV.

 

 

If you find any of the above confusing, post a comment and I will either edit or respond to the comment.

Free conversions

I've decided it is time to rid myself of all the conversions I have cluttering up my place.  I offer them at no cost to be picked up in central Texas.  Most are in or near running condition except for batteries; there are no good batteries.
http://www.evalbum.com/2314
The Leaf has been sold; there is an unlisted Neon.

On reflection, I think I will charge a $100 deposit to claim a car.  To be refunded on pick up.  Pick up to be done within 30 days of deposit.

I'm not interested in selling parts off the cars.

I'll answer questions publicly and post more information on this post.  Just post any questions as comments.

If you come to pick up a car and you can manage to bring me one or more good but bad battery 36v golf carts, you may be able to leave with cash in your pocket.

12/7/2020

Ranger is gone.  Still available: Zap, Neon, Jet/Escort.  The Jet/Escort may have historic value.  Converted in South Austin, Burleson Rd,  from Ford supplied gliders in fair volume.