Tesla Solar in Houston & Surrounding Area’s

[Jones1]

How many miles do you typically drive in a year? Let's say this is a Model Y - you should get 3 miles of driving for each kWh from the wall. If you're like me and drive about 10,000 miles/year then you should budget for an additional 3,333kWh per year for that car. A Cybertruck will get notably less miles for each kWh. Let's say it's only 2 miles for each kWh. 15,000 miles/year at that efficiency would require an additional 7,500kWh/year. This is on the high side because you won't be charging 100% at home with that many miles per year.

The solar system quote should give you a safe estimate of how many kWh it will produce each year. If you want to do your own estimates, you can use an online tool like PVwatts to put in the approximate solar system and array tilt and direction to get a production estimate.

PVWatts

Estimates the energy production and cost of energy of grid-connected photovoltaic (PV) energy systems throughout the world. It allows homeowners, small building owners, installers and manufacturers to easily develop estimates of the performance of potential PV installations

pvwatts.nrel.gov

Thanks. I used that website to help me decide on the 12kwh & 1PW. I believe I can charge at work. That will be about 25% of the time. I like others are hoping the Cybertruck could be used as a backup battery for the home like the F150 Lightning. Even though it is not confirmed by Tesla. It will probably need other equipment to make this possible. Just like the Ford Lightning. Looking at current electricity rates and Tesla‘s timeline to install. I’m glad I have a locked in rate with reliant @ .12-.13 cents For about 12 more months. Financing rates will go up higher. But I can always refinance later.

 

[jgleigh]

Also. Does anyone know if Tesla is only installing the Powerwall + now? I see Powerwall + on my documents. But it actually reads “Powerwall + Solar Discount”

The Powerwall+ is just the Powerwall 2 and the Tesla Inverter combined. It all depends on your system. I have 2 Powerwall+ and 2 Powerwall 2s.

 

[Rocket_man]

Wow. Thanks for the info. I haven’t talk to my PA yet. I was given an email To reach him. He has never responded. I call and get a random person.
As soon as i put my order in. It gave me a Site visit day. Maybe my pictures weren’t exact enough. So they have to do a survey. If this is going to take up to a year. I may put the down payment into some tesla stock. Until its time to pay. I live in Harris county. I believe its them not the city of Houston. That’s who l’ll have to deal with for permits and approval. I’m with Reliant now but the SA or lady i talked to last from Tesla. Told me to plan to switch retail provider to MP2 after they install. Tesla said they would help with that.

During the survey they looked at the roof penetrations (plumbing vents, exhaust vents etc) and went up in the attic and measured my roof rafters and spacing etc. They also looked at the locations for where the equipment could go and agreed that the PWs should be in the garage. That was the goal of the survey. This was the updated on the drawing. On installation day I spoke to the installers and they agreed to run the PV cables through the attic instead of over the roof. The interconnection agreement is with the company that owns the lines to your house, not your billing company. In Houston that is either CenterPoint or TNMP. I think my timeline was longer than most. There were several factors for that. Hopefully that is not the case for you.

 

[Jones1]

Now that I have a Tesla and I have placed an order for Solar. I see how the customer support and communication is the same. When you first put in an order. They barely talk or communicate with you. Then as you progress and get closer to certain dates and appointments. They will contact you and reply back faster. Tesla must have a training seminar. That they put there employees through.
1)Don’t respond to them. Until you have something to say.
2)Only answer the phone after a 30 minute wait.
3)Tell the customer. Everything will be on schedule unless it’s a delay.
4)When you finally have something to tell the customer. Email them and text them. Say it is urgent to respond. It may slow down there delivery.

If Chick-fil-A merged with Tesla customer service. Tesla would be the best Company in the world.

 

[wiltoking]

I have my site survey or visit on the 21st of June . I was hoping the install would happen in July. After hearing everyone’s stories. It may not happen until November.

Just found this thread, pretty cool to have all Houston info shared in one. Looks like you and I are almost in the same boat. I ordered at the end of April and just had the home assessment done on June 1st. The tech they send is very knowledgeable but he is just there to report what he sees. All changes have to go through Tesla Corporate, as others have said. Still, he did say that with design approval in June and the backlog, I would be seeing installation probably around October! Material seems to be in good supply of Tesla 400w panels for my system, just that they have a huge backlog (from last year it seems). Got a call from my PA pretty quickly after and reviewed the design drawings, all is approved on my end, so now just waiting.

 

[wiltoking]

If things go this fast that is great... but that was not my experience. A site survey was not a requirement for me, but I asked for one since they were insisting on putting the PW's on the outside of the house right where the gas connection/meter was. So the Site Survey took awhile, then they have to redo the design to move the PW's inside. Then once all this is done they have to submit a package to the city building department for a builders permit. Obviously this can vary greatly by how responsive your city building office is. My city has on-line access to permits and you can go look it up yourself. They also need to get the first part of the interconnection agreement with Centerpoint done. I'm on TNMP, maybe they are slower. If you PA is saying the PTO will take longer than getting it installed than I'm in trouble! I'm only 1.5 months short of a year into this thing.

Was there a reason the PW's can't be next to the gas connection/meter? After my survey, they located the PW inside the garage but they mentioned both options work and the installers can relocate when they show up if I want. There is a really good spot next to the meter and main disconnect to have it installed.

 

[wiltoking]

As for my system, it's 5.6kw with 1 PW, living in East Downtown. House is brand new and very energy efficient but just doesn't have a lot of roof area to work with. Sadly all the roof vents and penetrations are on the south side too. Can only fit 10 panels there at most. North is clear of obstructions but you lose ~30% production, so not adding too many panels. The system won't ever be able to charge my Model 3 either since I'm not back home until 6 pm. It would take an absurd number of PW's to be able to store energy for it to charge lol. The PW is really just a whim (it makes NO financial sense whatsoever to get one). At most, I can run a few evening hours off it and avoid losing power during quick power outages (had one last night for 4min). I guess the only plus side, is that in the event of a power outage during the day, the system can remain operational if there is enough sun. Also planning to switch to Free Nights Plan and charge then. This triples my day rate to 34c but by my calculations even without the panels, I should save vs my current Fixed Plan. Solar will just be gravy on top of that.

1 PW is very limited but due to the above, it doesn't make sense to get two. Right now Tesla wants to put the Air Handler (w/emergency heat coil) on the non-backup side yet they keep the Condenser backed up. This makes no sense to me and I'm trying to have them back up everything but they insist on adding a 2nd PW. The extreme scenario where it's night, running e-heat, and power fails would be pretty rare in Texas. I've gone thru my hourly power use and the only time this year where we did use e-heat, the home didn't pull more than 3kwh. But as everyone has said, they're very non-responsive but maybe the installers can wire it differently when they do get here.

 

[miimura]

As for my system, it's 5.6kw with 1 PW, living in East Downtown. House is brand new and very energy efficient but just doesn't have a lot of roof area to work with. Sadly all the roof vents and penetrations are on the south side too. Can only fit 10 panels there at most. North is clear of obstructions but you lose ~30% production, so not adding too many panels. The system won't ever be able to charge my Model 3 either since I'm not back home until 6 pm. It would take an absurd number of PW's to be able to store energy for it to charge lol. The PW is really just a whim (it makes NO financial sense whatsoever to get one). At most, I can run a few evening hours off it and avoid losing power during quick power outages (had one last night for 4min). I guess the only plus side, is that in the event of a power outage during the day, the system can remain operational if there is enough sun. Also planning to switch to Free Nights Plan and charge then. This triples my day rate to 34c but by my calculations even without the panels, I should save vs my current Fixed Plan. Solar will just be gravy on top of that.

1 PW is very limited but due to the above, it doesn't make sense to get two. Right now Tesla wants to put the Air Handler (w/emergency heat coil) on the non-backup side yet they keep the Condenser backed up. This makes no sense to me and I'm trying to have them back up everything but they insist on adding a 2nd PW. The extreme scenario where it's night, running e-heat, and power fails would be pretty rare in Texas. I've gone thru my hourly power use and the only time this year where we did use e-heat, the home didn't pull more than 3kwh. But as everyone has said, they're very non-responsive but maybe the installers can wire it differently when they do get here.

I have only 4.3kW of solar and two Powerwalls. I highly recommend you get your whole HVAC system backed up and get the two Powerwalls unless the money is really tight and you just can't afford it. Having the extra headroom in both power and energy with the second Powerwall is really nice to have.

 

[wiltoking]

I have only 4.3kW of solar and two Powerwalls. I highly recommend you get your whole HVAC system backed up and get the two Powerwalls unless the money is really tight and you just can't afford it. Having the extra headroom in both power and energy with the second Powerwall is really nice to have.

One PW could backup the HVAC system, it's just when it gets into the emergency heat that we reach the PW's limitations (max kw / max Amps). Feel like one, even with AC, is enough. Check out the power usage graph (6am M3 charging would always be from grid):

In the event of a major multi-day outtage, Texas Freez or Hurricane, I'd scale back my power use to keep only essentials running.

 

[Jones1]

Just found this thread, pretty cool to have all Houston info shared in one. Looks like you and I are almost in the same boat. I ordered at the end of April and just had the home assessment done on June 1st. The tech they send is very knowledgeable but he is just there to report what he sees. All changes have to go through Tesla Corporate, as others have said. Still, he did say that with design approval in June and the backlog, I would be seeing installation probably around October! Material seems to be in good supply of Tesla 400w panels for my system, just that they have a huge backlog (from last year it seems). Got a call from my PA pretty quickly after and reviewed the design drawings, all is approved on my end, so now just waiting.

Welcome. Thanks for contributing.

 

[Jones1]

I have only 4.3kW of solar and two Powerwalls. I highly recommend you get your whole HVAC system backed up and get the two Powerwalls unless the money is really tight and you just can't afford it. Having the extra headroom in both power and energy with the second Powerwall is really nice to have.

Wow. I’m a noob. I know Nothing about solar. I was thinking that a 4.3kwh system would not be enough to keep 2 Powerwall’s full of back up? Is it because of a low energy or kwh usage at your home? I was think 9.6 and 2 PW’s? Idk

 

[miimura]

Wow. I’m a noob. I know Nothing about solar. I was thinking that a 4.3kwh system would not be enough to keep 2 Powerwall’s full of back up? Is it because of a low energy or kwh usage at your home? I was think 9.6 and 2 PW’s? Idk

Without EV charging, my house probably uses a lot less energy than most people, especially Texans. I have no A/C in my house because of the coastal influence. My primary use for the Powerwalls is to avoid the punitive Peak electricity price of $0.43/kWh Winter and $0.56/kWh Summer. I can get through the higher rate periods from 3pm-12mid with about 10-12kWh of energy. That can be easily replaced by my small solar system unless there was significant cloud cover. However, with a single Powerwall, that would leave very little energy left for backup, and I probably wouldn't make it through the night if there was an outage. The fact that I'm daily discharging only 50% of the total capacity probably extends the battery lifetime too. I would love to have a much larger solar system to offset more of my bill, but it would not improve my Powerwall usage except in the lowest production 3 months of the year.

 

[Jones1]

I would love to have 2 or 3 powerwall's. It's just hard for me to see the value or return. I can get back over 10 years. My power has been out due to storms or other occurrences. Since I've been in our new house for the last couple of years. Not enough to spend $30,000 on PW's. I see the value I can get from Solar within the first few years. I also want the CyberTruck. So i have to be prepared to make that transaction. Hopefully in 2023-2024. If I could get a little lower of a system and add another PW. I would. I think I'm at 30 panels. 12kwh. I was at 9.6kwh or 24 panels. If I could get could get 26 panels and add another powerwall for $6000. Would be nice. I don't think the install price would change by much. for a few less panels.

 

[Zinc_Saucier]

I would love to have 2 or 3 powerwall's. It's just hard for me to see the value or return. I can get back over 10 years. My power has been out due to storms or other occurrences. Since I've been in our new house for the last couple of years. Not enough to spend $30,000 on PW's. I see the value I can get from Solar within the first few years. I also want the CyberTruck. So i have to be prepared to make that transaction. Hopefully in 2023-2024. If I could get a little lower of a system and add another PW. I would. I think I'm at 30 panels. 12kwh. I was at 9.6kwh or 24 panels. If I could get could get 26 panels and add another powerwall for $6000. Would be nice. I don't think the install price would change by much. for a few less panels.

Powerwalls should last for more than 10 years, that’s just the warranty period. However, even considering a longer period, they may not make financial sense. Only you can decide if the non-financial aspects make it worth it.

Unrelated, but solar arrays are measured in kW not kWh. A kW is an instantaneous measure of power, while kWh measure that power over time. So usage/generation is measured in kWh, but panels/instant power is measured in kW.

 

[Jones1]

Powerwalls should last for more than 10 years, that’s just the warranty period. However, even considering a longer period, they may not make financial sense. Only you can decide if the non-financial aspects make it worth it.

Unrelated, but solar arrays are measured in kW not kWh. A kW is an instantaneous measure of power, while kWh measure that power over time. So usage/generation is measured in kWh, but panels/instant power is measured in kW.

Thanks for the correction. Sorry for the error. I work with high electricity daily. I should be exact.

 

[Rocket_man]

Was there a reason the PW's can't be next to the gas connection/meter? After my survey, they located the PW inside the garage but they mentioned both options work and the installers can relocate when they show up if I want. There is a really good spot next to the meter and main disconnect to have it installed.

Centerpoint has rules on set-back distances from the gas stub for their meter equipment. On that side of the house not only do I have the gas line/meter, there is an electrical outlet, a fence, and the circuit breaker boxes. Just not enough room for two ~30" wide PWs that also need some separation from each other.

 

[Rocket_man]

As for my system, it's 5.6kw with 1 PW, living in East Downtown. House is brand new and very energy efficient but just doesn't have a lot of roof area to work with. Sadly all the roof vents and penetrations are on the south side too. Can only fit 10 panels there at most. North is clear of obstructions but you lose ~30% production, so not adding too many panels. The system won't ever be able to charge my Model 3 either since I'm not back home until 6 pm. It would take an absurd number of PW's to be able to store energy for it to charge lol. The PW is really just a whim (it makes NO financial sense whatsoever to get one). At most, I can run a few evening hours off it and avoid losing power during quick power outages (had one last night for 4min). I guess the only plus side, is that in the event of a power outage during the day, the system can remain operational if there is enough sun. Also planning to switch to Free Nights Plan and charge then. This triples my day rate to 34c but by my calculations even without the panels, I should save vs my current Fixed Plan. Solar will just be gravy on top of that.

1 PW is very limited but due to the above, it doesn't make sense to get two. Right now Tesla wants to put the Air Handler (w/emergency heat coil) on the non-backup side yet they keep the Condenser backed up. This makes no sense to me and I'm trying to have them back up everything but they insist on adding a 2nd PW. The extreme scenario where it's night, running e-heat, and power fails would be pretty rare in Texas. I've gone thru my hourly power use and the only time this year where we did use e-heat, the home didn't pull more than 3kwh. But as everyone has said, they're very non-responsive but maybe the installers can wire it differently when they do get here.

- If the roof penetrations are PVC Plumbing vents they may be able to cut them off and go over top of them. Probably some pros and cons on doing that but I agreed to do it on my roof and they were able to move panels around and have a more efficient layout. I could have put 10 more panels on that roof section where the designed thought it was maxed out.
- If you don't have at least one PW your solar may shut down during an outage. There is an explanation for this that someone more knowledgeable can elaborate, but the system needs power to control the off-grid configuration to make sure you don't send power back to the grid. If you can't do this the panels just shut off to prevent backfeeding the grid.
- If you have some loads on the PW backed up panel and some on a non-backed up panel, that will be reflected in the drawing package that gets submitted to the city permit office and will be approved that way. My guess is the installation crew may not want to make that kind of call during installation since the drawing would need to be changed to the as-built configuration. They revised the drawing for my house based on the on-the-fly re-arrangement of the PVs on the roof. So when the city sends its inspector and if they spotted that the install did not match the permit that might be an issue. But that would depend on the inspector. My city inspection was a look from about 5 feet and a 'looks good!' in like 30 seconds. But also, if you have a drawing of your system and a few years down the road you want to make changes, your drawing no longer matches what is built.

 

[cwied]

- If you don't have at least one PW your solar may shut down during an outage. There is an explanation for this that someone more knowledgeable can elaborate, but the system needs power to control the off-grid configuration to make sure you don't send power back to the grid. If you can't do this the panels just shut off to prevent backfeeding the grid.

In order for the solar panels to work during an outage, the house needs to be disconnected from the grid. The Powerwall system includes both the batteries and a gateway that has the switch that disconnects the house. It's not so much that you need power as that you need the switch to run during the outage.

Standard solar inverters are designed to shut down if the grid loses power because otherwise they would try to power the whole grid. The Powerwalls disconnect from the grid when there's an outage and fool the inverter into thinking the grid is still there by providing power. This allows the solar inverter to turn back on during an outage.

I believe Enphase has a new system where they can install a disconnect switch that is monitored by their micro inverters so they can turn back on even without batteries. The key benefit to the Powerwall system is that it works well with older inverters because they don't need to be aware that the house is disconnected. As far as they're concerned, the Powerwall is the grid.

 

[Jones1]

What’s the consensus on EMT or PVC piping? Is it better to have them run it through your attic making more holes in your roof? Or having Tesla install on the exterior down to the side of your house? I’m talking about piping the wire’s. Thanks

I can see a benefit for both. Just asking.

 

[wiltoking]

- If the roof penetrations are PVC Plumbing vents they may be able to cut them off and go over top of them. Probably some pros and cons on doing that but I agreed to do it on my roof and they were able to move panels around and have a more efficient layout. I could have put 10 more panels on that roof section where the designed thought it was maxed out.
- If you don't have at least one PW your solar may shut down during an outage. There is an explanation for this that someone more knowledgeable can elaborate, but the system needs power to control the off-grid configuration to make sure you don't send power back to the grid. If you can't do this the panels just shut off to prevent backfeeding the grid.
- If you have some loads on the PW backed up panel and some on a non-backed up panel, that will be reflected in the drawing package that gets submitted to the city permit office and will be approved that way. My guess is the installation crew may not want to make that kind of call during installation since the drawing would need to be changed to the as-built configuration. They revised the drawing for my house based on the on-the-fly re-arrangement of the PVs on the roof. So when the city sends its inspector and if they spotted that the install did not match the permit that might be an issue. But that would depend on the inspector. My city inspection was a look from about 5 feet and a 'looks good!' in like 30 seconds. But also, if you have a drawing of your system and a few years down the road you want to make changes, your drawing no longer matches what is built.

Yes, some of the nearest ones are PVC Plumbing vents, I think we can move two panels over to the South side without cutting anything off but the Tesla Rep that did the Site Visit mentioned it would be up to the installers to take more exact measurements. Honestly, he made it seem like they had a lot of flexibility. Saying things like "In the event the drawings changed then Tesla would resubmit to the City". Pitfall being that would delay PTO.

Thanks for the CenterPoint info tho, going to go check the spot where I think I can have the PW outside because it is near their gasline. The strange thing is that Tesla located the Backup Gateway outside the hom'se NW corner (near main breaker and CP Gas) and thats where the non-backed up loads get split. Whichs means they have to run new lines to the subpanel clear across the home to it's SE corner inside the garage just to power my Air Handler.