Time of Use Bill Credits with SCE

[fengshui]

Fengsui, everything you said makes sense.
I had believed that the payback replacing my super off peak electricity with solar panels would be slow because the cost difference of between super off peak electricity vs. solar is small. So by using this premise, I agree that I should only replace only my peak and nonpeak electricity with solar. I have been quoted a system with a break even point after 8 years.

However, another way to look at the problem is if I size my system to cover about 75% of my electric bill ($200). Then even though my superoff peak rate is so low, I still spend about $80 for the super off peak electricity. If I increase my system size to try to also cover the super off peak time also, I can STILL BREAK EVEN in about 8 years. The main differences between going with small vs. larger system is that after the 8 years, I will have a bill much closer to zero from SCE but had to payout more for a larger system. Also, with a larger system, the TOU plan is less important as you produce a 1:1 kWh for the electricity that you use vs. the electricity that you make. Please correct me if any of my statements do not seem sound.

My only quibble is that on TOU, if you go bigger, you will probably end up overproducing. The credits for Peak TOU are valuable enough that you'll end up with a negative bill even in the Spring and Fall, and won't have enough positive bill to subsume that. The flip side is that there's no guarantee that SCE will keep the EV-TOU rate around. The 1:1 production is best when you're on the standard schedule D. If you were to go bigger, I'd consider it insurance against future changes in rate plans over any other thing. A lot of this depends on your financial situation. If you have the money, a larger system is more versatile. If you are price-sensitive, then I'd scale lower and take the risk of a moderate bill at a future date.

I am leaning towards Sun power panels for aesthetics as my roof is very visible to the neighbors, and I am near 40 and don't want to have to repurchase solar again.

If you have the money and want the appearance of SunPower, go for it. They certainly are high-quality. I had one vendor quote me an 18-week wait for SunPower X-Panels, so make sure you ask your vendors what the lead time on the panels you want before making a final decision.

[J.P.M.]

If you have a Smart Meter, you can download hourly data for the past 13 months from SCE.com. Login and hit the Green Button download on the left side of the screen. You'll get a CSV file you can import into Excel. The date fields in that file will need to be transformed using DATEVALUE into fields that Excel understands as dates, but once that's done you can create a pivot table that aggregates all the data together by month and hour.

From there, you have lots of options. PVWatts will also give you projected production of a solar system on an hourly basis for your location, which is great for combining with your historical usage data to create projected net usage.

Thank You. You missed all the recent fireworks about PVWatts around here. I usually use SAM from NREL which is sort of like PVWatts on steroids, TRYNSYS or stuff I wrote. All use TMY data. SAM will let you generate your own TMY if you choose, including a completely clear day, whatever that means. SDG & E stuff is similar to SCE but not always (mostly) sketchy in terms of availability. My question was more along the lines of patterns of use, for example, the hourly average of all usage from 1500 to 1600 on March 18th for the last several years with an eye toward the possibility of time shifting usage, and/or investigating array orientation optimization to the extent possible during design phase.

[fengshui]

Thank You. You missed all the recent fireworks about PVWatts around here. I usually use SAM from NREL which is sort of like PVWatts on steroids, TRYNSYS or stuff I wrote. All use TMY data. SAM will let you generate your own TMY if you choose, including a completely clear day, whatever that means. SDG & E stuff is similar to SCE but not always (mostly) sketchy in terms of availability. My question was more along the lines of patterns of use, for example, the hourly average of all usage from 1500 to 1600 on March 18th for the last several years with an eye toward the possibility of time shifting usage, and/or investigating array orientation optimization to the extent possible during design phase.

SAM looks super-cool. I've already spent too many hours working through my usage and generation projections. I'm pretty happy with the results, but it's good to know there's another free tool.

As for your question, SCE doesn't appear to retain hourly data past 13 months, but you could visit annually to grab and hold their data to build up a multi-year record. An Energy Detective system retains hourly data, but only for 3 months.

[bcroe]

I usually use SAM from NREL which is sort of like PVWatts on steroids, TRYNSYS or stuff I wrote. All use TMY data. SAM will let you generate your own TMY if you choose, including a completely clear day

You still haven't explained to the rest of us, how to access & use this tool. Bruce Roe

[slopoke]

You still haven't explained to the rest of us, how to access & use this tool. Bruce Roe

Here is a link, I've never used this tool.

https://sam.nrel.gov/

[bcroe]

Down load

Here is a link, I've never used this tool. https://sam.nrel.gov/

Thanks, thats the first link i've seen since the beginning of the discussion.
There seems to be a link there for download. I'll have to get to the big
bandwidth access at the library and see what happens. Bruce Roe

[J.P.M.]

You still haven't explained to the rest of us, how to access & use this tool. Bruce Roe

Bruce:

I've sent you info on SAM access several times. When I started this business, I went to the NREL website and rooted around until I found SAM. It took me about 5 min. and I'm a computer Luddite. It would appear others have done the same as me. I'm not trying to be a wise ass, but I don't understand what the problem is.

[J.P.M.]

SAM looks super-cool. I've already spent too many hours working through my usage and generation projections. I'm pretty happy with the results, but it's good to know there's another free tool.

As for your question, SCE doesn't appear to retain hourly data past 13 months, but you could visit annually to grab and hold their data to build up a multi-year record. An Energy Detective system retains hourly data, but only for 3 months.

Understood. Thank you.

[bcroe]

Bruce: I've sent you info on SAM access several times. When
I started this business, I went to the NREL website and rooted around until I found SAM.
It took me about 5 min. and I'm a computer Luddite. It would appear others have done
the same as me. I'm not trying to be a wise ass, but I don't understand what the
problem is.

slopoke seemed to understand perfectly, my request for a link to get started. Spent
my career designing CPUs and related analog systems like power. Don't have a clue
around high level languages & programs.

I went to the link, found how to log in and apparently download. However, the download
seems to have failed; apparently it won't work on an Apple. Guess I need something
already on line. Bruce Roe

[silversaver]

slopoke seemed to understand perfectly, my request for a link to get started. Spent
my career designing CPUs and related analog systems like power. Don't have a clue
around high level languages & programs.

I went to the link, found how to log in and apparently download. However, the download
seems to have failed; apparently it won't work on an Apple. Guess I need something
already on line. Bruce Roe

Just register and download the application. Once downloaded, then install the app. There are both Windows and OS X. I have both version on my pc and mac book. Pretty much straight forward....

[bcroe]

Just register and download the application. Once downloaded, then install the app. There are both Windows and OS X. I have both version on my pc and mac book. Pretty much straight forward....

I think its easy to rebuild my automatic transmission, which I've done a couple dozen
times. Anything is easy when you know how. Thanks to slopoke for showing me
where to access SAM. There seems to be an issue in my "permissions" that won't allow
it to operate here; guess I'll have to go to the Apple store to sort that out. Bruce Roe

[inetdog]

I think its easy to rebuild my automatic transmission, which I've done a couple dozen
times. Anything is easy when you know how. Thanks to slopoke for showing me
where to access SAM. There seems to be an issue in my "permissions" that won't allow
it to operate here; guess I'll have to go to the Apple store to sort that out. Bruce Roe

Just make an appointment for the Genius Bar so you do not have to stand in line, and you will get excellent support.

The permissions involved are usually in the browser, although if the App uses Java (not JavaScript) there are some security lockdown issues.

[PrecisSolar]

Refer a Company

Hey you should really look into XXXX Solar, they are right off the 15 freeway. They have great customer service and offer free quotes. You should definitely give them a call (800 bend over). They can explain in detail how everything works. Check their website out as well xxxxsolar.com. They are the best!

Mod note - a neat company so great they can only afford stolen advertising?

[Ian S]

offer free quotes.

Wow! Imagine that. Free quotes. Whatever will they think of next?!!!

[slopoke]

Hey you should really look into xxxxxxxx, they are right off the 15 freeway. They have great customer service and offer free quotes. You should definitely give them a call (800) xxx-xxxx. They can explain in detail how everything works. Check their website out as well xxxxxxx.com. They are the best!

Wait for it........................