I once watched a very thoughtful discussion on this board about Solar. Who would you recommend? What to look out for?
OT. Solar
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Last: 2 yr ago by BearMDJD
If you are talking about solar power for you home, some things have changed, and more informationwvitbear said:
I once watched a very thoughtful discussion on this board about Solar. Who would you recommend? What to look out for?
may apply.
1.If you have smart metering, you can no longer swap kilowatt generated for kilowatt used. Instead of a one to one set off, it's based on time of day rates and you may have to deliver to your utility three kilowatts for each kilowatt used in the evening (the highest rate tier in my area).
2.When the utility power goes down, your solar system has to shut down as well to prevent power being dumped into the grid while crews at working on equipment.
3. If you are in a rural area with a potable water well, your utility could shut down power during an emergency, fire, earthquake, flood; and you couldn't use the power from your solar system.
4. Tier pricing rates are based on whether solar systems are generating, the highest tier stars at 4pm when most solar panels are providing a fraction of the power they generated midday. The cheapest tier rates are when solar panels are generating their peak power; aka you sell cheap, buy high.
5. Battery backups allow your system to sue power even during utility outages, without panels you can store power generated at midday (cheapest) cost to use during evening hours (highest delivered cost).
6. Tesla Powerwalls will likely require an expensive upgrade of electrical service, in my case from 200 watt to 400 watt. For me this would require a new load center and new service lines back to the transformer drop, replacing150 feet of under ground conduit due to larger cable size, a major additional cost. The reason for this upgrade has never been explained to me other than it is required.
7. Can you even install solar? My mother's house is in La Quinta is prohibited by the city from installing solar. The utility rate is much lower than in neighboring Palm Springs, about a third of what I pay in Chula Vista.
8. Newer higher output panels are now available than could reduce the roof footprint by 25%. In my case eliminating multiple locations.
9 Figure 40% of your kilowatt usage is during the peak demand (highest cost) evening tier, you will be purchasing power at this time, during the design phase the contractor should show this increased cost, it is not a one to one savings from solar power generated during the day. With smart meters utility cost for this period is about two thirds of your bill. Most estimates of savings do not correct for this very real cost.
10. Tax credit of 26% has been extended.
Been researching enphase batteries. The efficiency with their smart microinverters is pushing me to get those over the powerwalls.sp4149 said:If you are talking about solar power for you home, some things have changed, and more informationwvitbear said:
I once watched a very thoughtful discussion on this board about Solar. Who would you recommend? What to look out for?
may apply.
1.If you have smart metering, you can no longer swap kilowatt generated for kilowatt used. Instead of a one to one set off, it's based on time of day rates and you may have to deliver to your utility three kilowatts for each kilowatt used in the evening (the highest rate tier in my area).
2.When the utility power goes down, your solar system has to shut down as well to prevent power being dumped into the grid while crews at working on equipment.
3. If you are in a rural area with a potable water well, your utility could shut down power during an emergency, fire, earthquake, flood; and you couldn't use the power from your solar system.
4. Tier pricing rates are based on whether solar systems are generating, the highest tier stars at 4pm when most solar panels are providing a fraction of the power they generated midday. The cheapest tier rates are when solar panels are generating their peak power; aka you sell cheap, buy high.
5. Battery backups allow your system to sue power even during utility outages, without panels you can store power generated at midday (cheapest) cost to use during evening hours (highest delivered cost).
6. Tesla Powerwalls will likely require an expensive upgrade of electrical service, in my case from 200 watt to 400 watt. For me this would require a new load center and new service lines back to the transformer drop, replacing150 feet of under ground conduit due to larger cable size, a major additional cost. The reason for this upgrade has never been explained to me other than it is required.
7. Can you even install solar? My mother's house is in La Quinta is prohibited by the city from installing solar. The utility rate is much lower than in neighboring Palm Springs, about a third of what I pay in Chula Vista.
8. Newer higher output panels are now available than could reduce the roof footprint by 25%. In my case eliminating multiple locations.
9 Figure 40% of your kilowatt usage is during the peak demand (highest cost) evening tier, you will be purchasing power at this time, during the design phase the contractor should show this increased cost, it is not a one to one savings from solar power generated during the day. With smart meters utility cost for this period is about two thirds of your bill. Most estimates of savings do not correct for this very real cost.
10. Tax credit of 26% has been extended.
All these games being played (by PG&E mostly) as well as the financing around the panels and batteries is really off-putting.
These are my opinions, YMMV:
The biggest thing IMO that's misunderstood is that adding battery backup is much more to clear a regulatory hurdle than any performance shortcomings. Without battery backup, your PV system MUST have an automatic disconnect to shut it down when the grid goes down. (This is called "anti-islanding" in Code parlance.) However, WITH battery backup--regardless of how much--your PV system CAN, BUT WILL NOT NECESSARILY, BE equipped with a "smart switch" to isolate your system from the grid during a shutdown while still allowing it to continue to generate electricity. In a residential home you're never going to be able to add enough batteries to run your AC off them for any significant amount of time. The numbers just don't work. But with battery backup on sunny days you can keep generating power to run your AC. The million dollar question is does all that power have to cycle your batterty(ies) or can it bypass them? This will impact battery service life, but I've never been able to get it explained. In short, battery backup is to allow PV array to keep generating during PSPS events almost exclusively IMHO.
Other tidbits:
Unless cost is a barrier, I would design the system as "hybrid" to include wiring for a generator backup too. That way if smoke gets too dense you can still power AC during the day and charge battery(ies) for night (read: quiet) use when it's brutally hot.
If (or when) you upgrade your HVAC, I would go with an air heat pump (with LNG furnace "backup") rather than an AC unit. The reason is simple: heat pumps can do the same job as an AC unit when it's hot but can also generate electric heat when it's cold. They begin to lose efficiency when it gets really cold but that's not really a factor in most of CA, and you still have a furnace for any time it's not enough. Cost is only slightly more than AC unit.
For technicalities, see 2019 CEC Articles 690, 691, 705 here:
https://www.dgs.ca.gov/BSC/Codes
For install requirments, see PG&E Greenbook Manual
https://www.pge.com/en_US/large-business/services/building-and-renovation/greenbook-manual-online/greenbook-manual-online.page
The biggest thing IMO that's misunderstood is that adding battery backup is much more to clear a regulatory hurdle than any performance shortcomings. Without battery backup, your PV system MUST have an automatic disconnect to shut it down when the grid goes down. (This is called "anti-islanding" in Code parlance.) However, WITH battery backup--regardless of how much--your PV system CAN, BUT WILL NOT NECESSARILY, BE equipped with a "smart switch" to isolate your system from the grid during a shutdown while still allowing it to continue to generate electricity. In a residential home you're never going to be able to add enough batteries to run your AC off them for any significant amount of time. The numbers just don't work. But with battery backup on sunny days you can keep generating power to run your AC. The million dollar question is does all that power have to cycle your batterty(ies) or can it bypass them? This will impact battery service life, but I've never been able to get it explained. In short, battery backup is to allow PV array to keep generating during PSPS events almost exclusively IMHO.
Other tidbits:
Unless cost is a barrier, I would design the system as "hybrid" to include wiring for a generator backup too. That way if smoke gets too dense you can still power AC during the day and charge battery(ies) for night (read: quiet) use when it's brutally hot.
If (or when) you upgrade your HVAC, I would go with an air heat pump (with LNG furnace "backup") rather than an AC unit. The reason is simple: heat pumps can do the same job as an AC unit when it's hot but can also generate electric heat when it's cold. They begin to lose efficiency when it gets really cold but that's not really a factor in most of CA, and you still have a furnace for any time it's not enough. Cost is only slightly more than AC unit.
For technicalities, see 2019 CEC Articles 690, 691, 705 here:
https://www.dgs.ca.gov/BSC/Codes
For install requirments, see PG&E Greenbook Manual
https://www.pge.com/en_US/large-business/services/building-and-renovation/greenbook-manual-online/greenbook-manual-online.page
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https://www.skypowersolar.com/
I'm in the industry...these are accurate tips and comments. Thanks for educating folks.
bluehenbear said:
All these games being played (by PG&E mostly) as well as the financing around the panels and batteries is really off-putting.
What exactly are the games played by PG&E? I work for a utility not named PG&E and the regulatory framework around NEM 2.0 and NEM. 3.0 are some of the most complex out there. PG&E gets a lot of flack, most of it deserved (can't be killing people on a regularly basis), but I don't think this is one of those situations.
Tesla's solar customer service is the worst customer service I have ever experienced...and it is not even close.
Are you willing to answer a few questions I have?CannonBlast said:
I'm in the industry...
1) What is the source of the battery backup trigger to avoid anti-islanding? CEC 705.40 doesn't mention batteries at all and I haven't found it anywhere. My read of 705.40 is that interactive inverters should be allowed on a wide range of systems, including those without battery backup, but every equipment provider and installer I've ever spoken with always links them. Is it just a revenue thing or is there actual authority somewhere that I've missed?
2) Do you know how the circuitry works with interactive inverters? Say it's sunny but the grid is down, and my batteries are fully charged. If I turn on my AC will the power to run it cycle the batteries or bypass them unless and until they lose some charge and go back into a charging state?
EDIT
Code Ref
Quote:
705.40 Loss of Primary Source. Upon loss of primary source, an electric power production source shall be automatically disconnected from all ungrounded conductors of the primary source and shall not be reconnected until the primary source is restored.
Exception: A listed interactive inverter shall be permitted to automatically cease exporting power upon loss of primary source and shall not be required to automatically disconnect all ungrounded conductors from the primary source. A listed interactive inverter shall be permitted to automatically or manually resume exporting power to the utility once the primary source is restored.
Informational Note No. 1: Risks to personnel and equipment associated with the primary source could occur if an utility interactive electric power production source can operate as an intentional island. Special detection methods are required to determine that a primary source supply system outage has occurred and whether there should be automatic disconnection. When the primary source supply system is restored, special detection methods can be required to limit exposure of power production sources to out-of-phase reconnection.
Informational Note No. 2: Induction-generating equipment on systems with significant capacitance can become self-excited upon loss of the primary source and experience severe overvoltage as a result.
An interactive inverter shall be permitted to operate as a stand-alone system to supply loads that have been disconnected from electrical production and distribution network sources.
Totally agree. Tesla seems to think of solar as a tech device, rather than the fixtures they actually are. Particularly the seemingly doomed solar tiles. I've had this convo with a sales rep, they don't care.Calypso said:
Tesla's solar customer service is the worst customer service I have ever experienced...and it is not even close.
I'll DM you, Walter.
OK, thanks!
I'm interested in your answers to Walter's questions as well.CannonBlast said:
I'll DM you, Walter.
Yes me too.sp4149 said:I'm interested in your answers to Walter's questions as well.CannonBlast said:
I'll DM you, Walter.
Thanks. A lot of this is going over my head. Could you name a company or two in the Berkeley area where I can have them come out and discuss this.
As am I very interested in getting to the bottom of this. We've been told something similar, although in our case PV is already installed with NEM but without battery backup. I have no understanding of how or why simply adding batteries would impact the service cable sizing. Same "explanation" provided.sp4149 said:
6. Tesla Powerwalls will likely require an expensive upgrade of electrical service, in my case from 200 watt to 400 watt. For me this would require a new load center and new service lines back to the transformer drop, replacing150 feet of under ground conduit due to larger cable size, a major additional cost. The reason for this upgrade has never been explained to me other than it is required.
Obviously you don't want to back-feed the grid, but isn't that what transfer switches are for? Why can't you at least manually switch your panel when there's an outage, to rely solely on solar?CannonBlast said:
I'm in the industry...these are accurate tips and comments. Thanks for educating folks.
Walter - I have two questions.WalterSobchak said:As am I very interested in getting to the bottom of this. We've been told something similar, although in our case PV is already installed with NEM but without battery backup. I have no understanding of how or why simply adding batteries would impact the service cable sizing. Same "explanation" provided.sp4149 said:
6. Tesla Powerwalls will likely require an expensive upgrade of electrical service, in my case from 200 watt to 400 watt. For me this would require a new load center and new service lines back to the transformer drop, replacing150 feet of under ground conduit due to larger cable size, a major additional cost. The reason for this upgrade has never been explained to me other than it is required.
First - I have a Sunrun system on my house in the Hollywood Hills and it doesn't seem to generate enough electricity to fully impact my bill. Now I'm getting calls from other companies asking if I want to add another system plus a battery backup, which I'm interested in as I believe brown-outs will become increasingly more common. Do you have a company that services DWP customers you'd recommend.
Second - Do you roll on Shabbos?
Thanks
Andy
Andy,juarezbear said:Walter - I have two questions.WalterSobchak said:As am I very interested in getting to the bottom of this. We've been told something similar, although in our case PV is already installed with NEM but without battery backup. I have no understanding of how or why simply adding batteries would impact the service cable sizing. Same "explanation" provided.sp4149 said:
6. Tesla Powerwalls will likely require an expensive upgrade of electrical service, in my case from 200 watt to 400 watt. For me this would require a new load center and new service lines back to the transformer drop, replacing150 feet of under ground conduit due to larger cable size, a major additional cost. The reason for this upgrade has never been explained to me other than it is required.
First - I have a Sunrun system on my house in the Hollywood Hills and it doesn't seem to generate enough electricity to fully impact my bill. Now I'm getting calls from other companies asking if I want to add another system plus a battery backup, which I'm interested in as I believe brown-outs will become increasingly more common. Do you have a company that services DWP customers you'd recommend.
Second - Do you roll on Shabbos?
Thanks
Andy
I'm in San Diego served by SDG&E, but they seem to follow SoCalEd in billing practices. SDG&e installed Smart Meters a couple of years ago so that they could bill you by time of day service, instead of just a flat rate per kilowatt. This accomplished two things, first utility generation costs are low during 'green energy, generating hours (around midday) but at other times of day the utility company has to provide all the energy, at a much higher cost. Second this depresses the value of 'green energy' in the market place. Thus the utility buys energy from solar power during the day at the lowest price and then sells night time energy to the solar energy providers at a much higher price. Pretty effective at clobbering the competition.
Consider if your annual energy bill is for 10,000 kilowatt hours and you install a system that generates 10,000 Kwh, 6,000 kwh is consumed by your home and 4,000 is dumped into the grid at 10 cents per KWH and after dark you buy back 4,000 Kwh at 40 cents per Kwh. You saved $1,000 with solar power and you owe the electric company $1600 for peak demand usage charges, even though the power you generated, in total, equals the total power consumed. Until smart meters, you got a one to one exchange for power generated and would have very low electric costs, if any. Now that sweetheart deal is gone.
WalterSobchak said:As am I very interested in getting to the bottom of this. We've been told something similar, although in our case PV is already installed with NEM but without battery backup. I have no understanding of how or why simply adding batteries would impact the service cable sizing. Same "explanation" provided.sp4149 said:
6. Tesla Powerwalls will likely require an expensive upgrade of electrical service, in my case from 200 watt to 400 watt. For me this would require a new load center and new service lines back to the transformer drop, replacing150 feet of under ground conduit due to larger cable size, a major additional cost. The reason for this upgrade has never been explained to me other than it is required.
This is new to me also. I'm not an expert, but we just had solar + battery installed in our East Bay home a few months back. We had the similar issue of bumping up against our main panel's 100 amps when designing the system, but I assumed this was due to the size of the solar panel system, and not the battery. We have underground cabling also, so it would have been 1 year of PG&E permitting, 30k to dig up the driveway and install new 200 (or 400!) amp wiring, which was a nonstarter for us.
The company we used was able to just fit our system into our 100 amp main panel to make the math work. We don't have a huge solar panel system - a little over 5kW.
If you were told to upgrade from a 200 to a 400 amp main panel, you must have an extremely large house with a swimming pool, multiple AC units, electric cars and a lot more?
We can't run our AC unit when our system is islanded - the initial energy surge would blow the inverter when turning on. As stated above, a heat pump AC system doesn't have this problem, so that would be the preferred cooling system. Then again, we have a small battery since they are so darn expensive, so we probably wouldn't run our AC in a power outage anyway - it would drain the battery extremely quickly. Our battery is just enough to run our fridges, turn on some lights, and charge our devices (as well as do some PG&E rate arbitrage!).
The economics of solar panels are a no brainer if you are planning to stay in your house for a while. The economics of batteries is terrible - at today's prices it is merely a luxury and will never pay for itself.
If you want to see why energy costs vary so much during the day, get the California ISO App., ISO Today.
These graphs don't even take into account much, if any, home system generation
These graphs don't even take into account much, if any, home system generation
C'mon Andy, you know what I told those ****s down at the league office...
I wish I could be of more help to everyone, but I'm just sorting through all of this myself.
I agree that PSPS events will unfortunately be increasing in frequency, and probably also duration.
So NEM isn't my focus. I work with it because that's the system but I'm planning for outages, not cost savings.
I don't have any company I can really recommend. Lots of this is hold your nose type deals.
I'm just the type of person who likes to understand how things work so I do way too much research.
We're in NorCal anyway so I wouldn't know where to start for LA. Sorry I couldn't be more help.
I wish I could be of more help to everyone, but I'm just sorting through all of this myself.
I agree that PSPS events will unfortunately be increasing in frequency, and probably also duration.
So NEM isn't my focus. I work with it because that's the system but I'm planning for outages, not cost savings.
I don't have any company I can really recommend. Lots of this is hold your nose type deals.
I'm just the type of person who likes to understand how things work so I do way too much research.
We're in NorCal anyway so I wouldn't know where to start for LA. Sorry I couldn't be more help.
On a related note, the huge US tariffs on Chinese solar panels is just bad policy. The premise behind them is that China subsidizes solar production and sells below cost.
Let's think this out. If China were to give us free solar panels, would we not take them? What if all our electricity was based on free solar panels, solar pumped hydro storage and free energy from the sun? Would that be "bad" for the US? No it would be great for us and great for the planet.
The excuse is that we are protecting US solar panel production (5% of our use) but of course the big money backing the policy is from oil and gas interests.
Let's think this out. If China were to give us free solar panels, would we not take them? What if all our electricity was based on free solar panels, solar pumped hydro storage and free energy from the sun? Would that be "bad" for the US? No it would be great for us and great for the planet.
The excuse is that we are protecting US solar panel production (5% of our use) but of course the big money backing the policy is from oil and gas interests.
A fish rots from the head down.WalterSobchak said:Totally agree. Tesla seems to think of solar as a tech device, rather than the fixtures they actually are. Particularly the seemingly doomed solar tiles. I've had this convo with a sales rep, they don't care.Calypso said:
Tesla's solar customer service is the worst customer service I have ever experienced...and it is not even close.
One answer to your China proposition: HP Printers.calumnus said:
On a related note, the huge US tariffs on Chinese solar panels is just bad policy. The premise behind them is that China subsidizes solar production and sells below cost.
Let's think this out. If China were to give us free solar panels, would we not take them? What if all our electricity was based on free solar panels, solar pumped hydro storage and free energy from the sun? Would that be "bad" for the US? No it would be great for us and great for the planet.
The excuse is that we are protecting US solar panel production (5% of our use) but of course the big money backing the policy is from oil and gas interests.
Then, there's quality, environmental harm from substd materials production and manufacturing, free today (not that anything is)/expensive tomorrow, upcharges, buying from enemy.
Who ya wanna do business with? US businesses (no matter how you think of them) or businesses controlled by a controlled economy?
Genius!WalterSobchak said:
C'mon Andy, you know what I told those ****s down at the league office...
I wish I could be of more help to everyone, but I'm just sorting through all of this myself.
I agree that PSPS events will unfortunately be increasing in frequency, and probably also duration.
So NEM isn't my focus. I work with it because that's the system but I'm planning for outages, not cost savings.
I don't have any company I can really recommend. Lots of this is hold your nose type deals.
I'm just the type of person who likes to understand how things work so I do way too much research.
We're in NorCal anyway so I wouldn't know where to start for LA. Sorry I couldn't be more help.
I just installed solar in the last month. Here are my thoughts:
1. My original priority was backup capacity. I looked at a generator and the cost for a "real" whole home generator running off of natural gas was around $8-10K. And with that set up, I'm out of luck if there's no natural gas (earthquake).
2. So I started looking at Tesla Powerwall. Good backup solution - more expensive but 26% tax credits IF YOU ALSO INSTALL SOLAR. I'm told there's a bill to change that - in the future it may be possible to get a comparable tax credit for battery back up only.
Weeds comment: Apparently you can get the tax credit for your entire project. I'm told that may include roof replacement if its part of solar (not sure if that's still the case and I didn't need a roof).
3. Tesla is now the price leader - they are selling solar and powerwalls as widgets. System size is small, medium, large, ex large. Panels look good and perform reasonably well, but the technology is less desirable (string inverter, not microinverter). I believe all installation work is subcontracted and in terms of warranty, is Tesla a good 20 year bet? (you decide). And, as noted, the customer service is reputably awful.
String inverter means all panels are linked to a single inverter usually on the side of your house. Microinveter means each panel has its own inverter that converts the power before sending it to your panel. Microinverter is, in most applications, more efficient but more expensive (but not by much). Some panels have integrated microinverters (manufacturer makes both) others use third party, typically Enphase (which is a solid/reputable company).
4. So I got a price from Tesla and used that to shop other providers. My attitude was basically "how much more do I have to pay for customer service and better panels?" I got pricing and decided I was willing to pay for an "upgrade." Note you can get Tesla powerwalls from other providers (more on that below).
5. Once I had an idea of what I wanted, I used energysage.com to get bids. I have no affiliation with the site. But it is a site with seemingly unbiased info (panel ratings, etc.) that also operates as a marketplace to get bids without giving out your personal info (until you want to). The site also has ratings for the different companies providing bids. It is interesting to get bids from different companies - they offer different solutions, etc. Note that all of the companies now do preliminary estimates based on google earth pictures of your roof - most of the proposals I received had the same basic set up albeit with different equipment. This will show you how good your roof is for panels. https://www.google.com/get/sunroof
6. When I had bids, here is what I looked at: (i) panel efficiency and warranty lengthy/scope (does it include labor); (ii) inverter type (I picked microinverter); (iii) who is issuing the warranty for the panels and inverter - sometimes it is not the same company; and (iv) total system output. Like buying a tv, buying the "newest most efficient panel" means paying a significant premium. Sunpower has the "best" panels but they are significantly more expensive. Some of this is dictated by your roof size and orientation - if there is limited usable space for solar panels, then you may have to pay for more efficient panels to achieve your desired system size.
I narrowed my choice down to "one level below premium" LG and Panasonic panels, two of the better more established companies (there are others). Panasonic offers a slightly better warranty (all inclusive) but their panels are not as efficient. I picked an LG panel with an integrated LG microinverter - I felt that way I had one company responsible for everything.
7. Picking the installation company is dicey. I went with a local installer with a 20 year history and good reputation. I'm relying on them for warranty of the roof penetration and some labor - but for the most part my warranty is from LG. Also, you should look to see if the warranty is transferrable.
8. I opted to get powerwalls. But they are on back order - so they broke my project in two. I have the solar installed and powerwalls will come later when available. I suspect that if I had ordered direct from Tesla, I would not have encountered this issue. So if you are doing poweralls, make sure you ask your installer re availability/timing.
9. Pro tip: If you are in a high fire area, look into the SGIP program. You can check fire zone location here:
https://www.arcgis.com/apps/webappviewer/index.html?id=e4d7d4cc0c0743dbb836f3177a021074&extent=-13513596.7108%2C3889703.1691%2C-12584122.4469%2C4490192.4633%2C102100
If you are in a fire zone, check out this link: https://sites.energycenter.org/sgip The point of the program is to provide back up power for those "in need" who are likely to need it because of power shut offs in fire zones.
If you can qualify, your powerwall batteries will likely be free (or nearly so). This is not available if you go through tesla for reasons I don't fully understand (I think they exceeded their allotment of rebate).
Here is the detailed breakdown of equity resiliency requirements. The most likely qualification for people on this board is if you're in a fire zone and need medical equipment.
https://www.cpuc.ca.gov/uploadedFiles/CPUCWebsite/Content/News_Room/NewsUpdates/2020/Residential%20Equity%20and%20Equity%20Resiliency%20Matrix.pdf
10. Regarding the batteries, it was a dual decision for me. I get the backup I wanted - the original reason I started on this path. But by switching to time of use ratings and using the batteries during high cost times (4-9 pm.), my bill should be reduced as well. You need to size your system to ensure the batteries can charge up and you have enough generation capacity to offset most of your use. The installers do the math for that. But if done correctly, you should be able to nearly zero out your bill (if that's your goal).
Final note: the 26% tax credit was supposed to reduce to 22% on 1/1/21. It was extended in one of the covid bills - not sure for how long. I had LENGHTY delays in getting permits - so if you want the credit this year, I suggest you start now.
On the whole, I'm happy with the decisions I made. But I've only been up and running for a few weeks.
1. My original priority was backup capacity. I looked at a generator and the cost for a "real" whole home generator running off of natural gas was around $8-10K. And with that set up, I'm out of luck if there's no natural gas (earthquake).
2. So I started looking at Tesla Powerwall. Good backup solution - more expensive but 26% tax credits IF YOU ALSO INSTALL SOLAR. I'm told there's a bill to change that - in the future it may be possible to get a comparable tax credit for battery back up only.
Weeds comment: Apparently you can get the tax credit for your entire project. I'm told that may include roof replacement if its part of solar (not sure if that's still the case and I didn't need a roof).
3. Tesla is now the price leader - they are selling solar and powerwalls as widgets. System size is small, medium, large, ex large. Panels look good and perform reasonably well, but the technology is less desirable (string inverter, not microinverter). I believe all installation work is subcontracted and in terms of warranty, is Tesla a good 20 year bet? (you decide). And, as noted, the customer service is reputably awful.
String inverter means all panels are linked to a single inverter usually on the side of your house. Microinveter means each panel has its own inverter that converts the power before sending it to your panel. Microinverter is, in most applications, more efficient but more expensive (but not by much). Some panels have integrated microinverters (manufacturer makes both) others use third party, typically Enphase (which is a solid/reputable company).
4. So I got a price from Tesla and used that to shop other providers. My attitude was basically "how much more do I have to pay for customer service and better panels?" I got pricing and decided I was willing to pay for an "upgrade." Note you can get Tesla powerwalls from other providers (more on that below).
5. Once I had an idea of what I wanted, I used energysage.com to get bids. I have no affiliation with the site. But it is a site with seemingly unbiased info (panel ratings, etc.) that also operates as a marketplace to get bids without giving out your personal info (until you want to). The site also has ratings for the different companies providing bids. It is interesting to get bids from different companies - they offer different solutions, etc. Note that all of the companies now do preliminary estimates based on google earth pictures of your roof - most of the proposals I received had the same basic set up albeit with different equipment. This will show you how good your roof is for panels. https://www.google.com/get/sunroof
6. When I had bids, here is what I looked at: (i) panel efficiency and warranty lengthy/scope (does it include labor); (ii) inverter type (I picked microinverter); (iii) who is issuing the warranty for the panels and inverter - sometimes it is not the same company; and (iv) total system output. Like buying a tv, buying the "newest most efficient panel" means paying a significant premium. Sunpower has the "best" panels but they are significantly more expensive. Some of this is dictated by your roof size and orientation - if there is limited usable space for solar panels, then you may have to pay for more efficient panels to achieve your desired system size.
I narrowed my choice down to "one level below premium" LG and Panasonic panels, two of the better more established companies (there are others). Panasonic offers a slightly better warranty (all inclusive) but their panels are not as efficient. I picked an LG panel with an integrated LG microinverter - I felt that way I had one company responsible for everything.
7. Picking the installation company is dicey. I went with a local installer with a 20 year history and good reputation. I'm relying on them for warranty of the roof penetration and some labor - but for the most part my warranty is from LG. Also, you should look to see if the warranty is transferrable.
8. I opted to get powerwalls. But they are on back order - so they broke my project in two. I have the solar installed and powerwalls will come later when available. I suspect that if I had ordered direct from Tesla, I would not have encountered this issue. So if you are doing poweralls, make sure you ask your installer re availability/timing.
9. Pro tip: If you are in a high fire area, look into the SGIP program. You can check fire zone location here:
https://www.arcgis.com/apps/webappviewer/index.html?id=e4d7d4cc0c0743dbb836f3177a021074&extent=-13513596.7108%2C3889703.1691%2C-12584122.4469%2C4490192.4633%2C102100
If you are in a fire zone, check out this link: https://sites.energycenter.org/sgip The point of the program is to provide back up power for those "in need" who are likely to need it because of power shut offs in fire zones.
If you can qualify, your powerwall batteries will likely be free (or nearly so). This is not available if you go through tesla for reasons I don't fully understand (I think they exceeded their allotment of rebate).
Here is the detailed breakdown of equity resiliency requirements. The most likely qualification for people on this board is if you're in a fire zone and need medical equipment.
https://www.cpuc.ca.gov/uploadedFiles/CPUCWebsite/Content/News_Room/NewsUpdates/2020/Residential%20Equity%20and%20Equity%20Resiliency%20Matrix.pdf
10. Regarding the batteries, it was a dual decision for me. I get the backup I wanted - the original reason I started on this path. But by switching to time of use ratings and using the batteries during high cost times (4-9 pm.), my bill should be reduced as well. You need to size your system to ensure the batteries can charge up and you have enough generation capacity to offset most of your use. The installers do the math for that. But if done correctly, you should be able to nearly zero out your bill (if that's your goal).
Final note: the 26% tax credit was supposed to reduce to 22% on 1/1/21. It was extended in one of the covid bills - not sure for how long. I had LENGHTY delays in getting permits - so if you want the credit this year, I suggest you start now.
On the whole, I'm happy with the decisions I made. But I've only been up and running for a few weeks.
I just passed my first year with solar panels. Obviously my experience in Texas is going to be different than if I was still in CA, but FWIW here's my observations.
1. I was surprised there still isn't a one-to-one KwH buyback with PG&E. Before moving to TX in 2008, I rented a room for a couple years in a house with solar and PG&E had the same restrictions then. I thought it would have changed by now.
2. I switched power providers to Green Mountain Energy since they have the one-to-one buyback without restrictions. If I do need to import power, it's a fixed rate, (VERY important in Texas as so many painfully found out during our freeze a few weeks ago).
3. I haven't looked into battery back up yet so no comment.
4. In case of power outage the panels stop sending electricity to the grid.
5. I keep careful track of production. I built up credits in the fall and spring but when summer hits, production did not keep up with the power used by the AC. If you've ever been here in summer, AC is vital.
6. So far my panels, despite our usual Hell's Front Porch summer last year are producing 97% of my electricity. Calculating in the cost of the panels as opposed to my electric bill before I saved about $500 last year.
1. I was surprised there still isn't a one-to-one KwH buyback with PG&E. Before moving to TX in 2008, I rented a room for a couple years in a house with solar and PG&E had the same restrictions then. I thought it would have changed by now.
2. I switched power providers to Green Mountain Energy since they have the one-to-one buyback without restrictions. If I do need to import power, it's a fixed rate, (VERY important in Texas as so many painfully found out during our freeze a few weeks ago).
3. I haven't looked into battery back up yet so no comment.
4. In case of power outage the panels stop sending electricity to the grid.
5. I keep careful track of production. I built up credits in the fall and spring but when summer hits, production did not keep up with the power used by the AC. If you've ever been here in summer, AC is vital.
6. So far my panels, despite our usual Hell's Front Porch summer last year are producing 97% of my electricity. Calculating in the cost of the panels as opposed to my electric bill before I saved about $500 last year.
Rushinbear said:One answer to your China proposition: HP Printers.calumnus said:
On a related note, the huge US tariffs on Chinese solar panels is just bad policy. The premise behind them is that China subsidizes solar production and sells below cost.
Let's think this out. If China were to give us free solar panels, would we not take them? What if all our electricity was based on free solar panels, solar pumped hydro storage and free energy from the sun? Would that be "bad" for the US? No it would be great for us and great for the planet.
The excuse is that we are protecting US solar panel production (5% of our use) but of course the big money backing the policy is from oil and gas interests.
Then, there's quality, environmental harm from substd materials production and manufacturing, free today (not that anything is)/expensive tomorrow, upcharges, buying from enemy.
Who ya wanna do business with? US businesses (no matter how you think of them) or businesses controlled by a controlled economy?
If they are truly selling below cost, just buy more and bankrupt your "enemy" while saving money making the rest of your economy more efficient with lower energy costs and letting the market instead direct capital to the many US businesses that are efficient and profitable on a global scale without protectionism.
If my roof is 12 years old (and in good shape as far as I know), is it a bad idea to get solar? If my roof needs replacing in 10 or 15 years, seems like it would add a lot of expense.
Has anyone here looked into a generator that has solar panels (and also can be powered by propane)? I live in oakland so no need for air conditioning but 3000sq ft house and we do use a good amount of power. I think I might be leaning towards this rather than solar for my roof as it's a smaller investment and I don't know how long we'll stay in California.
Has anyone here looked into a generator that has solar panels (and also can be powered by propane)? I live in oakland so no need for air conditioning but 3000sq ft house and we do use a good amount of power. I think I might be leaning towards this rather than solar for my roof as it's a smaller investment and I don't know how long we'll stay in California.
75bear said:WalterSobchak said:As am I very interested in getting to the bottom of this. We've been told something similar, although in our case PV is already installed with NEM but without battery backup. I have no understanding of how or why simply adding batteries would impact the service cable sizing. Same "explanation" provided.sp4149 said:
6. Tesla Powerwalls will likely require an expensive upgrade of electrical service, in my case from 200 watt to 400 watt. For me this would require a new load center and new service lines back to the transformer drop, replacing150 feet of under ground conduit due to larger cable size, a major additional cost. The reason for this upgrade has never been explained to me other than it is required.
This is new to me also. I'm not an expert, but we just had solar + battery installed in our East Bay home a few months back. We had the similar issue of bumping up against our main panel's 100 amps when designing the system, but I assumed this was due to the size of the solar panel system, and not the battery. We have underground cabling also, so it would have been 1 year of PG&E permitting, 30k to dig up the driveway and install new 200 (or 400!) amp wiring, which was a nonstarter for us.
The company we used was able to just fit our system into our 100 amp main panel to make the math work. We don't have a huge solar panel system - a little over 5kW.
If you were told to upgrade from a 200 to a 400 amp main panel, you must have an extremely large house with a swimming pool, multiple AC units, electric cars and a lot more?
We can't run our AC unit when our system is islanded - the initial energy surge would blow the inverter when turning on. As stated above, a heat pump AC system doesn't have this problem, so that would be the preferred cooling system. Then again, we have a small battery since they are so darn expensive, so we probably wouldn't run our AC in a power outage anyway - it would drain the battery extremely quickly. Our battery is just enough to run our fridges, turn on some lights, and charge our devices (as well as do some PG&E rate arbitrage!).
The economics of solar panels are a no brainer if you are planning to stay in your house for a while. The economics of batteries is terrible - at today's prices it is merely a luxury and will never pay for itself.
We installed solar panels on our house about 10 years ago and have had a major reduction in our monthly electricity bills.
I have read many financial advisors reports that it taxes X years to earn back the cost of the solar panel installation. But I decided to do it anyway since I was in my 60's and was looking to reduce my monthly living expenses in preparation for the day I no longer had a job and had to live on fixed income.
Last year with all the power outages I looked into either adding a solar battery backup or a generator backup for my house.
It turned out that the cost of battery back up (with all its tax incentives) was break even with the cost of a large generator (with all the costs of permanent installation - concrete pad a safe distance from the house and sound deadening enclosure - and with the cost of maintenance and fuel). Plus the battery backup had the ability to reduce our electricity bill even more than our solar panels alone. The choice became a no-brainer.
We have a 3,000 sq foot house in the Oakland hills and need only one large TESLA panel. We have no AC or big power drawing equipment. We have a gas stove and water heater. We merely want to keep our lights and TV/computers and refrigerator working. We were told that if we lived over the hill in Lafayette or Walnut Creek we would have needed a second TESLA battery stacked in tandem.
Note: the "large" battery is really NOT very large. It is about 4 feet high and 3 feet wide but only about 4 INCHES deep. It is not very noticeable on the side of our house; a white flat battery on a white wall. Although at night it has a spooky X-Files green glow around its edges.
As a final point, we did not have to change our wiring (in 1993 we had a major remodeling and upgraded our wiring from 100 amps to 200 amps). Our 200 amp panel could easily handle up to 2 large batteries.
Final comment: we have been told that our one panel should be able to power our house for 24-48 hours depending upon how many appliances we run ( and provided we don't operate our electric clothes
dryer). That should be more than adequate since even on cloudy days our solar panels generate some level of energy.
GivemTheAxe said:75bear said:WalterSobchak said:As am I very interested in getting to the bottom of this. We've been told something similar, although in our case PV is already installed with NEM but without battery backup. I have no understanding of how or why simply adding batteries would impact the service cable sizing. Same "explanation" provided.sp4149 said:
6. Tesla Powerwalls will likely require an expensive upgrade of electrical service, in my case from 200 watt to 400 watt. For me this would require a new load center and new service lines back to the transformer drop, replacing150 feet of under ground conduit due to larger cable size, a major additional cost. The reason for this upgrade has never been explained to me other than it is required.
This is new to me also. I'm not an expert, but we just had solar + battery installed in our East Bay home a few months back. We had the similar issue of bumping up against our main panel's 100 amps when designing the system, but I assumed this was due to the size of the solar panel system, and not the battery. We have underground cabling also, so it would have been 1 year of PG&E permitting, 30k to dig up the driveway and install new 200 (or 400!) amp wiring, which was a nonstarter for us.
The company we used was able to just fit our system into our 100 amp main panel to make the math work. We don't have a huge solar panel system - a little over 5kW.
If you were told to upgrade from a 200 to a 400 amp main panel, you must have an extremely large house with a swimming pool, multiple AC units, electric cars and a lot more?
We can't run our AC unit when our system is islanded - the initial energy surge would blow the inverter when turning on. As stated above, a heat pump AC system doesn't have this problem, so that would be the preferred cooling system. Then again, we have a small battery since they are so darn expensive, so we probably wouldn't run our AC in a power outage anyway - it would drain the battery extremely quickly. Our battery is just enough to run our fridges, turn on some lights, and charge our devices (as well as do some PG&E rate arbitrage!).
The economics of solar panels are a no brainer if you are planning to stay in your house for a while. The economics of batteries is terrible - at today's prices it is merely a luxury and will never pay for itself.
We installed solar panels on our house about 10 years ago and have had a major reduction in our monthly electricity bills.
I have read many financial advisors reports that it taxes X years to earn back the cost of the solar panel installation. But I decided to do it anyway since I was in my 60's still earning a salary and was looking to reduce my monthly living expenses in preparation for the day I no longer had a job and had to live on fixed income.
(What some financial advisers fail to appreciate is that a financial decision should take into account cash flow timing considerations and not simply compare long term gross costs vs gross savings.)
Last year with all the power outages I looked into either adding a solar battery backup or a generator backup for my house.
It turned out that the cost of battery back up (with all its tax incentives) was break even with the cost of a large generator (with all the costs of permanent installation - concrete pad a safe distance from the house and sound deadening enclosure - and with the cost of maintenance and fuel). Plus the battery backup had the ability to reduce our electricity bill even more than our solar panels alone. The choice became a no-brainer.
We have a 3,000 sq foot house in the Oakland hills and need only one large TESLA panel. We have no AC or big power drawing equipment. We have a gas stove and water heater. We merely want to keep our lights and TV/computers and refrigerator working. We were told that if we lived over the hill in Lafayette or Walnut Creek we would have needed a second TESLA battery stacked in tandem.
Note: the "large" battery is really NOT very large. It is about 4 feet high and 3 feet wide but only about 4 INCHES deep. It is not very noticeable on the side of our house; a white flat battery on a white wall. Although at night it has a spooky X-Files green glow around its edges.
As a final point, we did not have to change our wiring (in 1993 we had a major remodeling and upgraded our wiring from 100 amps to 200 amps). Our 200 amp panel could easily handle up to 2 large batteries.
Final comment: we have been told that our one panel should be able to power our house for 24-48 hours depending upon how many appliances we run ( and provided we don't operate our electric clothes
dryer). That should be more than adequate since even on cloudy days our solar panels generate some level of energy.
I looked at portable generator options. I can't imagine there is a reasonably sized solar generator that can operate with enough power to run an entire house. There are some that will run appliances and serve as limited emergency power and those seemed to be priced in the$2000+ range .dmh65 said:
If my roof is 12 years old (and in good shape as far as I know), is it a bad idea to get solar? If my roof needs replacing in 10 or 15 years, seems like it would add a lot of expense.
Has anyone here looked into a generator that has solar panels (and also can be powered by propane)? I live in oakland so no need for air conditioning but 3000sq ft house and we do use a good amount of power. I think I might be leaning towards this rather than solar for my roof as it's a smaller investment and I don't know how long we'll stay in California.
There are some generators that will run off of gasoline/propane/natural gas. Here is a model I saw at costco for around $900 that looked like it would provide ample power to my house in emergency scenarios (i.e., enough to power the important things).
https://www.costco.com/firman-7500w-running--9400w-peak-tri-fuel-generator.product.100648883.html
Here are the issues I found:
1. To run power to your house, you'll need to have an electrician install a connection that allows you to plug the generator into the main panel. If you're planning to use natural gas, you would need to have a plumber install a connection to a gas line as well (my plumber said it was pretty easy to do as long as there's a gas line in reasonable proximity to your panel).
2. The generator requires periodic maintenance, so you need to be diligent about that. I didn't trust myself. And stored gasoline doesn't last very long unless you buy a special additive that is pretty expensive and extra maintenance is required if you use gasoline. So you'll probably want to run on propane or gas. In an emergency scenario, are you confident about your supply of those things? Probably yes for the wildfire related outages, but less certain in the case of an earthquake.
3. I believe the generators are somewhat loud. In an emergency, who cares perhaps. But all your neighbors will likely know and be stopping by to charge up. LOL.
I would definitely proceed with caution in that case. I will send you a direct message about my experience here.dmh65 said:
If my roof is 12 years old (and in good shape as far as I know), is it a bad idea to get solar? If my roof needs replacing in 10 or 15 years, seems like it would add a lot of expense.
Has anyone here looked into a generator that has solar panels (and also can be powered by propane)? I live in oakland so no need for air conditioning but 3000sq ft house and we do use a good amount of power. I think I might be leaning towards this rather than solar for my roof as it's a smaller investment and I don't know how long we'll stay in California.
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