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Getting a more than "properly sized" system under SMUD

Black306

Member
Oct 14, 2019
580
839
Sacramento
Teetering on getting solar. One thing holding me back is SMUD saying "In order to qualify for Net Energy Metering, the system must be sized to generate no more energy than your past 12-month’s energy history." Using their WattPlan estimator, that means a 6.3kW system max. I'd like to get a Tesla 8.16kW system cause I expect electrical use to go up in a couple years. (I'll be driving the 3 more, Cybertruck will arrive, wife will stop complaining about turning off the AC during the summer, etc.) Now, I did read somewhere that SMUD may make exceptions if electrical demand is expected to increase, however, I haven't seen anything about that on their site.

Anyone have issues getting SMUD to OK-to-install a system that is ~30% larger than the previous 12-months of consumption? Or qualify for net metering with a larger than "properly sized" system?
 

jjrandorin

Moderator, Model 3, Tesla Energy Forums
Nov 28, 2018
9,635
10,874
Riverside Co. CA
What @MJ_CA_2019 said. Most utilities have a forum you can sign that says you expect to increase your electrical usage in the next 12 months because of X / Y. They generally wont let you double your usage but I doubt they will have an issue with a system size of 8.X when your usage is 6.X, with that form.
 

Uncle Paul

Well-Known Member
Nov 1, 2013
6,296
6,866
Canyon Lake,CA
This used to be a bigger deal than currently.

Speak with Tesla as to what your utilities are currently accepting.

In my case, I ordered a system slightly smaller than usage. This gave me the quickest return on my investment. Can always install additional panels later. Still have a small utility bill, but the up front cost savings were significant.

It used to be that Solar companies would encourage you to buy the largest system you could get away with, but with Tesla, they charge the same prices for kWh in all their configurations. No cost incentives to put in a larger system than necessary.

This also incentivizes me to continue to be conservative in my energy use.
 

jjrandorin

Moderator, Model 3, Tesla Energy Forums
Nov 28, 2018
9,635
10,874
Riverside Co. CA
This used to be a bigger deal than currently.

Speak with Tesla as to what your utilities are currently accepting.

In my case, I ordered a system slightly smaller than usage. This gave me the quickest return on my investment. Can always install additional panels later. Still have a small utility bill, but the up front cost savings were significant.

It used to be that Solar companies would encourage you to buy the largest system you could get away with, but with Tesla, they charge the same prices for kWh in all their configurations. No cost incentives to put in a larger system than necessary.

This also incentivizes me to continue to be conservative in my energy use.

To each their own, but one of the biggest benefits to me of having solar is having enough to NOT have to "worry about conservation" that much because my energy is coming from the sun, not the grid, and NOT having much of a bill from the utility other than the standard connection charges.
 

h2ofun

Active Member
Aug 11, 2020
2,684
492
auburn, ca
To each their own, but one of the biggest benefits to me of having solar is having enough to NOT have to "worry about conservation" that much because my energy is coming from the sun, not the grid, and NOT having much of a bill from the utility other than the standard connection charges.
I agree, which is why I might try to add another 5 to 15K. Its now or never with NEM3 coming
 

charlesj

Active Member
Oct 22, 2019
1,197
254
Monterey, CA
I know OP is in Sacramento apparently not a PG&E customer but PG&E at least allows or allowed 110% of previous years usage in my case.
Yes, tell them you are expanding very soon to those electric cars, etc.
 

brian.c

Member
Apr 7, 2021
104
57
Rocklin, ca
This used to be a bigger deal than currently.

Speak with Tesla as to what your utilities are currently accepting.

In my case, I ordered a system slightly smaller than usage. This gave me the quickest return on my investment. Can always install additional panels later. Still have a small utility bill, but the up front cost savings were significant.

It used to be that Solar companies would encourage you to buy the largest system you could get away with, but with Tesla, they charge the same prices for kWh in all their configurations. No cost incentives to put in a larger system than necessary.

This also incentivizes me to continue to be conservative in my energy use.
This was my thinking on my first system, I almost immediately regretted it. I thought I could just add a few more panels later, then comes to find out no one wants to do that. Only option was to install a completely separate system, which is what I am in the process of doing now. If I could go back, I would have increased the size... At that time, I think we were paying about 12 cents per kwh, now we are at 28 cents or more. So basically for the last 10 years been paying more and more to PG&E and doing everything to conserve. Now after buying an EV, its a must to install a second system. Now I have to deal with the NEM rules of adding a second system, which messes up the grandfathering rules etc. My new system is 175% of last years bill, so hoping no issues. After adding on the EV charging, we will still be oversized a bit, and should have enough room for a second EV in the near future. We also plan to run the AC more, now that we are all working from home, indefinitely.
 

h2ofun

Active Member
Aug 11, 2020
2,684
492
auburn, ca
This was my thinking on my first system, I almost immediately regretted it. I thought I could just add a few more panels later, then comes to find out no one wants to do that. Only option was to install a completely separate system, which is what I am in the process of doing now. If I could go back, I would have increased the size... At that time, I think we were paying about 12 cents per kwh, now we are at 28 cents or more. So basically for the last 10 years been paying more and more to PG&E and doing everything to conserve. Now after buying an EV, its a must to install a second system. Now I have to deal with the NEM rules of adding a second system, which messes up the grandfathering rules etc. My new system is 175% of last years bill, so hoping no issues. After adding on the EV charging, we will still be oversized a bit, and should have enough room for a second EV in the near future. We also plan to run the AC more, now that we are all working from home, indefinitely.
when I put on my solar, I had no data usage. Installed recommended a certain size. I then went back and said how much solar can you put on my house so I could get max tax credit. So we put 14K on a 11.4 SE inverter. Filled up my south facing and best west facing. SO glad I did this, now that I have the batteries. But, it really is not enough for the batteries. So looking at putting stuff on my north facing sides, and adding a few more on my south and west. These will not be ideal, but would be better than nothing. I again told them I want a price for the most I could get one, and cost for different wattage. I told them I think my restriction is now on string sizes. Luckily installed a second 11.4K inverter which for what I have is stupid. BUT, for adding more panels, that stuff is ready to go.

So if I can have 18 panels per string, and 3 strings per inverter, this would give me a little over 100 panels I could install. Still waiting for the bid.
 

Black306

Member
Oct 14, 2019
580
839
Sacramento
To each their own, but one of the biggest benefits to me of having solar is having enough to NOT have to "worry about conservation" that much because my energy is coming from the sun, not the grid, and NOT having much of a bill from the utility other than the standard connection charges.
Ditto. I'm sure my wife will also enjoy not having the smart thermostats turn off the AC during summer peak rates. 😁


I know OP is in Sacramento apparently not a PG&E customer but PG&E at least allows or allowed 110% of previous years usage in my case.
Yes, tell them you are expanding very soon to those electric cars, etc.
PG&E customer, but not for electricity; for gas. Electricity is coming from SMUD.


This was my thinking on my first system, I almost immediately regretted it. I thought I could just add a few more panels later, then comes to find out no one wants to do that. Only option was to install a completely separate system, which is what I am in the process of doing now. If I could go back, I would have increased the size... At that time, I think we were paying about 12 cents per kwh, now we are at 28 cents or more. So basically for the last 10 years been paying more and more to PG&E and doing everything to conserve. Now after buying an EV, its a must to install a second system. Now I have to deal with the NEM rules of adding a second system, which messes up the grandfathering rules etc. My new system is 175% of last years bill, so hoping no issues. After adding on the EV charging, we will still be oversized a bit, and should have enough room for a second EV in the near future. We also plan to run the AC more, now that we are all working from home, indefinitely.
Wife and I have a saying; "spend money once." So I have no issue going a little bigger than currently needed. Also, I'm not a fan of people walking on my roof and potentially cracking tiles (water leaks). So I don't mind going bigger to avoid a redo of people working on the roof.
 

jjrandorin

Moderator, Model 3, Tesla Energy Forums
Nov 28, 2018
9,635
10,874
Riverside Co. CA
"Adding panels" is not something that people do, to existing PV systems, unless they are the ones that installed them in the first place (either self installed, or are the company that installed the panels in the firs place).

In general, one PV company will not touch another companies work in that manner, so if / when you go to add panels later, you will, in general, be adding a new, separate system, with its own inverter.

Exceptions are, if the company who installed your first system is still there, still servicing your area, and sized your system such that it makes sense to add on, then you might be able to do it.

TL ; DR, PV systems are not something one generally "adds a few panels to, if I want to go bigger later". If one is focused on "ROI" then better return on investment usually comes from undersizing a bit (a bit faster payoff). In general, though, people use more power when they get solar. Try convincing a significant other that you have to still turn the thermostat off during peak times after you get solar (for example) and be prepared for a somewhat difficult discussion on what you spend the money for (lol).

This kind of stuff (in my opinion) is the type of thing where people, in general, never regret going "too big" but many people regret going too small. One can usually find a way to use the extra power, and, at least to me, it feels nice to both "not worry about electric conservation" and also know that "I am doing my part, as I use almost no power from the grid for large portions of the year" at the same time.
 

MorrisonHiker

S 100D 2021.12.25.7
Mar 8, 2015
9,849
9,212
Colorado
"Adding panels" is not something that people do, to existing PV systems, unless they are the ones that installed them in the first place (either self installed, or are the company that installed the panels in the firs place).

In general, one PV company will not touch another companies work in that manner, so if / when you go to add panels later, you will, in general, be adding a new, separate system, with its own inverter.

Exceptions are, if the company who installed your first system is still there, still servicing your area, and sized your system such that it makes sense to add on, then you might be able to do it.

TL ; DR, PV systems are not something one generally "adds a few panels to, if I want to go bigger later". If one is focused on "ROI" then better return on investment usually comes from undersizing a bit (a bit faster payoff). In general, though, people use more power when they get solar. Try convincing a significant other that you have to still turn the thermostat off during peak times after you get solar (for example) and be prepared for a somewhat difficult discussion on what you spend the money for (lol).

This kind of stuff (in my opinion) is the type of thing where people, in general, never regret going "too big" but many people regret going too small. One can usually find a way to use the extra power, and, at least to me, it feels nice to both "not worry about electric conservation" and also know that "I am doing my part, as I use almost no power from the grid for large portions of the year" at the same time.
Our utility allows a solar system that is sized up to 120% of the previous 12 months usage. They also allow 3000 kWh per vehicle if you've purchased an EV and don't have 4 months of usage reflected. We knew our original 16.5 kW system wouldn't be enough but it was the largest our utility would allow at the time. We had to wait a year and then with those bills we were able to justify another 4 kW system. We were skeptical that even a 20.5 kW system would be enough but as luck would have it, I got to start working from home thanks to COVID three months after we expanded to 20.5 kW. We ended up with over 4000 kWh surplus production for 2020. The surplus generated between March and October rolls over and helps cover our November-February electric bills when our system doesn't have a surplus.
 
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h2ofun

Active Member
Aug 11, 2020
2,684
492
auburn, ca
Our utility allows a solar system that is sized up to 120% of the previous 12 months usage. They also allow 3000 kWh per vehicle if you've purchased an EV and don't have 4 months of usage reflected. We knew our original 16.5 kW system wouldn't be enough but it was the largest our utility would allow at the time. We had to wait a year and then with those bills we were able to justify another 4 kW system. We were skeptical that even a 20.5 kW system would be enough but as luck would have it, I got to start working from home thanks to COVID three months after we expanded to 20.5 kW. We ended up with over 4000 kWh surplus production for 2020. The surplus generated between March and October rolls over and helps cover our November-February electric bills when our system doesn't have a surplus.
I am hoping there also is a piece on size of solar based on how many batteries one has. Ever hear of this? I also thought I heard usage for like 3 years, not one?
 

MorrisonHiker

S 100D 2021.12.25.7
Mar 8, 2015
9,849
9,212
Colorado
I am hoping there also is a piece on size of solar based on how many batteries one has. Ever hear of this? I also thought I heard usage for like 3 years, not one?
For Xcel Energy in Colorado, they only allow 120% of the past 12 months usage plus 3000 kWh for any newly purchased vehicle not included for 4 months out of those 12 months. There's no exception based on Powerwalls/batteries.

Other places around the country are quite different. Someone above mentioned SMUD only allows 100% of the last 12 months usage. Other places seemingly have no restrictions on how much solar you can install.
 

charlesj

Active Member
Oct 22, 2019
1,197
254
Monterey, CA
...
PG&E customer, but not for electricity; for gas. Electricity is coming from SMUD.


...
Does SMUD own the electric infrastructure too? If not, it is a municipal or community agency for buying electricity from wholesalers and sell to you. PG&E would still get a payment for infrastructure charges, etc.
I think Santa Clara owns all the infrastructure and but electricity from generators. Very inexpensive when I saw my son's bill a number of years ago.
 

Black306

Member
Oct 14, 2019
580
839
Sacramento
Does SMUD own the electric infrastructure too? If not, it is a municipal or community agency for buying electricity from wholesalers and sell to you. PG&E would still get a payment for infrastructure charges, etc.
I think Santa Clara owns all the infrastructure and but electricity from generators. Very inexpensive when I saw my son's bill a number of years ago.
It’s a community-owned org. Power comes from multiple sources, but they’re heavy on solar. Current production is something like ~150MW and adding another ~250MW capacity in a couple years. That’s another reason for my hesitation; prices are relatively cheap. Rates are down to ~$0.09/kW off peak and after EV discount. Well, except for the summer time peak rate; that’s ~$0.31/kW. 😁
 
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