6kW system in Agoura Hills

[gvl]

Depending on your orientation, I doubt losing the 1st. hr. in the A.M. will cost you 1,000 kWh/yr. More like about half that much or so.

It's more than 1hr I'm afraid. For example today PVWATTS thinks I should be generating 0kW@5am, 1.5kW@6am, 3.2kW@7am, and 4.7kW@8am AC from a 8kW DC system, and there was absolutely no sun on the roof until 7:30. Approximating linearly I would miss about 5kWh of production today. I don't know how this will be distributed over all months, but I suspect the duration of shading will not be constant.

[J.P.M.]

I've just realized I'm missing at least an hour of early sunshine every morning due to some hills to the East side of my home which is going to cost me 1000 kWh or so annually. Sounds like my plan to size the array smaller isn't going to work out after all.

Depending on your orientation, I doubt losing the 1st. hr. in the A.M. will cost you 1,000 kWh/yr. More like about half that much or so.

Keep the use reduction goals in place.

[gvl]

I've just realized I'm missing at least an hour of early sunshine every morning due to some hills to the East side of my home which is going to cost me 1000 kWh or so annually. Sounds like my plan to size the array smaller isn't going to work out after all.

[J.P.M.]

It is a 1970 tract home, my understanding home builders of that period did set the bar really low in terms of construction quality. The same huge flat SE roof area I plan to use for solar install is exposed to the sun from the early morning and during hottest hours of the day, so I think it is to blame for the heat build-up. There is insulation in the attic and walls, but I suppose there is room for improvement. We will definitely keep one gas car, but my daughter will start driving in 3-4 years, so the plan is to give her our Leaf as I suspect its resale value will be close to that of popcorn by that time and I might be able to get my hands on some new EV tech

Tract homes may get a bad rap, but they aren't usually thought of as good examples of energy conservation's latest/greatest.

[gvl]

So I wrote a little program that parses SCE hourly usage and pvwatts hourly generation estimates and ran it against my actual usage for the last 12 months, even for that non-TOU-optimized usage a 8kW should have generated enough credits to bring the total close to $0, so 10kW is definitely an overkill. While I don't expect to be able to significantly change my usage patters a better plan it seems is to install a 8kW system and save $4k after incentives, and invest $2k into a variable-speed pool pump that can probably save me another 2000kWh annually, and since it is quiet I can use it during super off-peak and save even more.

[gvl]

I feel your pain I was going through the same issues.

As I suspected you area is hotter. Do you have a new or older home? Insulation might provide cheaper alternative.

I am not planning on a second ev, prefer to keep one car gas for now in case there ever is an issue with power outage etc.

It is a 1970 tract home, my understanding home builders of that period did set the bar really low in terms of construction quality. The same huge flat SE roof area I plan to use for solar install is exposed to the sun from the early morning and during hottest hours of the day, so I think it is to blame for the heat build-up. There is insulation in the attic and walls, but I suppose there is room for improvement. We will definitely keep one gas car, but my daughter will start driving in 3-4 years, so the plan is to give her our Leaf as I suspect its resale value will be close to that of popcorn by that time and I might be able to get my hands on some new EV tech

[Gmoney!]

I feel your pain I was going through the same issues.

As I suspected you area is hotter. Do you have a new or older home? Insulation might provide cheaper alternative.

I am not planning on a second ev, prefer to keep one car gas for now in case there ever is an issue with power outage etc.

[gvl]

Yes I factored summer.. We are in Murrieta so climate is similar to yours although we get a nice cool breeze in afternoons which you dont get being in agoura. I am very familiar with your area lived in Thousand Oaks most my life.

Last summer in Temecula we hardly ran the AC but we were able to deal with 80 deg temps inside, not everyone can. Even with running the AC here and there i will have plenty of juice. I didnt deal with degredation aside from whatever the pvwatt default was... Over time the kids will move out of the house so our demand should decline, of course that isnt for another 20 years haha.

Gotta get the spreadsheet out and factor it all in to figure it out. For me, TOU-A was the best plan and a 5.1 system was more than sufficient. If I get rid of my car it will be slight overkill but I think we will probably keep the ev long term now.

My A/C was on almost full-time August-September last year struggling to keep the temps inside the home at 78F, without the A/C the temps on the second floor were 90+ F on certain days, few can deal with that Usage was 1500 to 2000 kWh during those months. I hope solar panels will keep the roof cooler which should help with the A/C usage in the summer. My usage for winter months is consistent with yours.

Need to get to the spreadsheets, but I get a feeling 7kW ballpark is what I need to 0-out my current bill with controlled approach as to when to use big loads. Adding 3kW will pretty much allow me not to worry what to run and when, while also providing a slightly better $/Wt cost ratio plus room for expansion like a 2nd EV 2-3 years down the road, which is quite likely given the promises about improved battery technology materialize. The payback period will likely be about 1.5 years longer which is worse but not the end of the world either. And on top of it, as they've already shown, SCE may screw up EV customers with undersized solar/TOU by enforcing less favorable TOU rates any day while making it more difficult to add additional capacities in the future. Decision, decisions.

[Gmoney!]

Where are you located? Did you factor in the summer months? I may not be able to shift out all of my summer A/C usage out of on-peak due to kids get home from school at 3pm or spend whole day at home during summer break so I expect my 5 ton system to be on full blast during that time, me and my wife work from home 30% of the time as well, plus pets. Then there is panel degradation over time. Guess no other way but to spend some time with spreadsheets to see how much downsizing I can tolerate.

Yes I factored summer.. We are in Murrieta so climate is similar to yours although we get a nice cool breeze in afternoons which you dont get being in agoura. I am very familiar with your area lived in Thousand Oaks most my life.

Last summer in Temecula we hardly ran the AC but we were able to deal with 80 deg temps inside, not everyone can. Even with running the AC here and there i will have plenty of juice. I didnt deal with degredation aside from whatever the pvwatt default was... Over time the kids will move out of the house so our demand should decline, of course that isnt for another 20 years haha.

Gotta get the spreadsheet out and factor it all in to figure it out. For me, TOU-A was the best plan and a 5.1 system was more than sufficient. If I get rid of my car it will be slight overkill but I think we will probably keep the ev long term now.

[gvl]

I'll make sure to read the contract carefully and understand the warranty terms. I'm handy and comfortable working with electricity, so can do certain things myself, like remove/reinstall the inverter, which gives me some comfort. Problems like roof leaks that require removal of all panels are a concern of course.

[silversaver]

You mean it is an additional warranty from the installer? I thought that Enphase already covers both parts/labor for 25 years, and SolarEdge does that for the optimizers but not the inverter which is only covered for the hardware and not the labor.

Enphase doesn't cover the labor part....etc. Like you said, no one knew what will be coming. The labor part is something you should look into.

It will be extra if your installer mention both parts and labor coverage for 20yrs, right?

[gvl]

Depends on your installer. Few recently installation job from my friends, the installers have cover either 20yrs (string inverter) or 25yrs (Enphase) both parts and labors which I think it is a big plus.

You mean it is an additional warranty from the installer? I thought that Enphase already covers both parts/labor for 25 years, and SolarEdge does that for the optimizers but not the inverter which is only covered for the hardware and not the labor.

[gvl]

Installation went well, waiting for city inspection now.

I do not have 12 month data as i just bought the house but my first two months we were consuming around 1100-1200 kwh, majority of that was car and pool pump so i can shift that usage to off peak.

Where are you located? Did you factor in the summer months? I may not be able to shift out all of my summer A/C usage out of on-peak due to kids get home from school at 3pm or spend whole day at home during summer break so I expect my 5 ton system to be on full blast during that time, me and my wife work from home 30% of the time as well, plus pets. Then there is panel degradation over time. Guess no other way but to spend some time with spreadsheets to see how much downsizing I can tolerate.

[silversaver]

+1. You can buy an extended warranty that goes to 25 years on SolarEdge above 7.5kW for $745 as opposed to the 12 you get with the product. I wouldn't do it for the reasons stated above. There is always a chance your unit goes kaput late in the standard warranty window and you get a new one or at least a failure-prone component inside the inverter will be replaced. I'd rather bet on that than on SolarEdge/Enphase being in business in 20 years.

Depends on your installer. Few recently installation job from my friends, the installers have cover either 20yrs (string inverter) or 25yrs (Enphase) both parts and labors which I think it is a big plus. One of the installer actually only starting solar about 4 yrs ago, but they are in water heater/AC business for 26yrs, so I am sure they will be around for the next 20yrs. The price for solar has really drop in recent yrs, it is not hard to get a decent pricing with longer warranty coverage.

[J.P.M.]

+1. You can buy an extended warranty that goes to 25 years on SolarEdge above 7.5kW for $745 as opposed to the 12 you get with the product. I wouldn't do it for the reasons stated above. There is always a chance your unit goes kaput late in the standard warranty window and you get a new one or at least a failure-prone component inside the inverter will be replaced. I'd rather bet on that than on SolarEdge/Enphase being in business in 20 years.

Opinions vary. I'd not bet the farm on much of anything lasting 20 years at this point.