Thinking to Add more Solar to Offset Charging but...

[Glamisduner]

I signed up for usage alerts and just got one.

Estimated Cost to Date
$291.40
Forecasted Bill this Month
$440 - $596

Holy cow + my $250 a month solar loan.

Looks like I am back to paying $800 a month for power now that San Diego Gouge and Extortion has changed the billing rates.

 

[Sandiegodoug]

Yep
And it goes up11% in January

 

[smatthew]

I can't use a tesla power wall as it is a DC system. I'd have to go with a different brand that would work with AC inverters (that's what I was told anyways).

That was PowerWall 1, which I believe is no longer in production. PowerWall 2 has a built in inverter - it only accepts and outputs AC power.

 

[abasile]

I can't use a tesla power wall as it is a DC system. I'd have to go with a different brand that would work with AC inverters (that's what I was told anyways).

The original Powerwall was DC-based, but the current model, the Powerwall 2, is AC-based. It has a built-in inverter. Our solar panels have micro-inverters and they play with our Powerwalls just fine.

However even though you have to overproduce and buy back power at a higher rate, it's still cheaper to add more panels than add a power wall. The power wall give your a backup source in case of an outage, but is not the best solution for lowering your bill. (or so I am told).

Yes, I expect this is true for most people. To justify a Powerwall for "TOU load shifting", you need to have a great deal of peak usage . I'd agree that adding more solar panels would be the way to go. When you're maxed out on panels, a Powerwall could be the next step.

In our case, we're in a semi-rural mountain area and we've had enough power outages in the past that our Powerwalls are valuable to us for backup purposes. There's also the cool factor, as I enjoy watching the app and seeing our 8 AM - 10 PM energy come almost entirely from our solar panels and batteries (our 10PM - 8AM nighttime energy comes from the grid at cheap rates, mainly to charge our EVs).

 

[Glamisduner]

The original Powerwall was DC-based, but the current model, the Powerwall 2, is AC-based. It has a built-in inverter. Our solar panels have micro-inverters and they play with our Powerwalls just fine.


Yes, I expect this is true for most people. To justify a Powerwall for "TOU load shifting", you need to have a great deal of peak usage . I'd agree that adding more solar panels would be the way to go. When you're maxed out on panels, a Powerwall could be the next step.

In our case, we're in a semi-rural mountain area and we've had enough power outages in the past that our Powerwalls are valuable to us for backup purposes. There's also the cool factor, as I enjoy watching the app and seeing our 8 AM - 10 PM energy come almost entirely from our solar panels and batteries (our 10PM - 8AM nighttime energy comes from the grid at cheap rates, mainly to charge our EVs).

I think I'm going to switch to EV TOU after this giant power bill. But it will be interesting to see if it actually saves me money. No AC or laundry between 4-9 is harsh since thats when I'm home from work but maybe it will work out.

On the bright side, the guy that installed our system came out and recommends full system panel replacement due to delamination of the panel and that's what he is going to try to get warranty replacement for. We will see how that goes! Said they might offer to replace all 32 panels, or just give me the money back for them, but either way new panels can't be a bad thing right? He also said I can add about 6-7 more panels because we have 2 sets of inverters. Or if I'm going to a NEM2 plan anyways, maybe just replace the smaller inverter with a bigger one.

 

[Sandiegodoug]

I would try to keep nem 1. Increase your system by 10% . My installer says tou a bad deal for solar customers on nem 1. Sdge told me I was better off staying on the tiered plan. I only pay 1 bill yearly at true up.
(Natural gas is due monthly)

 

[Glamisduner]

I would try to keep nem 1. Increase your system by 10% . My installer says tou a bad deal for solar customers on nem 1. Sdge told me I was better off staying on the tiered plan. I only pay 1 bill yearly at true up.
(Natural gas is due monthly)

He isn't wrong, at least if you can stay in tier1. You pay 27 cens per kwh to charge, but you get one for one on power credits. So for every kwh you produce they give you one kwh credit to use anytime. Where under Nem2 and EZV-TOU where you produce at .09 cents and then get charged 57 cents per KwH (on the weekends).

I seem to be well beyond that 10% need though (I need to produce about 100 more than I am now to cover AC and volt charging, along with running the refrigerators etc), and my usage will drastically increase with getting a full electric car instead of the volt, although I'm sure it would help some.

I'll probably have to switch to TOU EV2. SDG&E does not give an estimate for EV charging plans like they do for the other TOU plans so you have to kind of guess. After one year you can switch back though if the EV plan is not cheaper. Of course I won't really have anything to compare it with.

Right now my power bill is estimated to be $600 + $250 for my 32 panel solar loan. so $850 on power this month. We have the AC set to 78 when it's hot, but it looks like I will be changing it to 80+ for the next 2 weeks to try to keep my total costs closer to $600

 

[Sandiegodoug]

Another option is to supercharge your 3 during air conditioning season. My 3 charges really fast and I see Tesla has plans for one in Escondido. I visit the supercharger
During air season to help keep my bill near zero. I think it’s like 11 bucks to fill.

 

[abasile]

Another option is to supercharge your 3 during air conditioning season. My 3 charges really fast and I see Tesla has plans for one in Escondido. I visit the supercharger during air season to help keep my bill near zero. I think it’s like 11 bucks to fill.

If it costs you about $11 to Supercharge (sounds like 40+ kWh at $0.26/kWh), then even if you have to pay peak rates at home, it shouldn't cost more than about double that. Supercharging is of course fine for the battery pack, and I would have no hesitation to rely on Superchargers if that were my only option because I had to park on the street every night, but Supercharging is not as optimal for long-term battery health as regular home charging. Is it really worth your time to go out of your way to Supercharge rather than just charging at home?

Worst case, suppose one has a really lousy electric rate plan and it costs a bit more to charge at home than to drive a Prius or a cheap economy car. You still get to drive a freakin' Tesla with your own, private "refueling" station!

 

[Glamisduner]

If it costs you about $11 to Supercharge (sounds like 40+ kWh at $0.26/kWh), then even if you have to pay peak rates at home, it shouldn't cost more than about double that. Supercharging is of course fine for the battery pack, and I would have no hesitation to rely on Superchargers if that were my only option because I had to park on the street every night, but Supercharging is not as optimal for long-term battery health as regular home charging. Is it really worth your time to go out of your way to Supercharge rather than just charging at home?

Worst case, suppose one has a really lousy electric rate plan and it costs a bit more to charge at home than to drive a Prius or a cheap economy car. You still get to drive a freakin' Tesla with your own, private "refueling" station!

My $600+ monthly power bill while only charging a volt, (no full ev yet) thinks it might be worth it to supercharge for free. 20 minute stop every night (or when I feel like it) would take a huge chunk out of my power bill if I stay in NEM1 plan but I do worry about battery depredation doing this.
the tesla will need 2-3x the charging my volt uses due to my commute, so I can see my current power plan costing $1000 a month when I start powering the tesla (gas and electric are close during peak power, actually it's cheaper to operate my volt on gas right now than it is to charge it. AND GAS is $4 a gallon here.

At this current time, it's very questionable if EV charging plan would actually benefit me. Right now even running the AC we are overproducing for 6-7 hours durring the day but the car (chevy volt) and whole house fan suck up more power than we produced in excess. So I still end up in tier 2/3 of the power plan. We have used over 738 kw this month and look be be on track to use close to 1000. I have now set our AC to 80 degrees while we are home.

The downside to EVZ charging plan is:
$16 a month extra fee.
On the weekends power is cheap only 9 cents per KwH until 2:00, but then it changes to 24 sents from 4-9 still, so everything we overproduced will quickly be depleted since we only get 9 cents per kwh hah.

Still I think I will try the EV plan before I resort to supercharging. Ideal would be to have the EV charging plan and charge on the weekends from 10-2:00 Because then I am actually getting full benefit form the panels. and not returning anything to the grid. Once you switch to a NEM2 plan, it's in your best interest to not send power back on the grid (well sorta anyways)

 

[Sandiegodoug]

Free supercharger use is the ticket during air season. Still think staying in nem1 is the ticket. Sdge would love to get rid of all the nem 1 customers because we cost them money. More panels is the answer while we still get 30% tax credit. Sdge rates going up 28% over next 4 years. God help those that don’t have solar.

 

[Glamisduner]

Here is my usage chart, we left the house around 1:00 and came home around 11:00.

You can see that car charging is the bulk of my bill, we did not run the AC at all yesterday and used the whole house fan at night to cool the house after we got home.

You can see appliance use once our solar stops producing. Under 500 watts which may seem like allot, but I have a Kegerator, a refrigerator (it needs to be replaced, but we need to remodel to fit a larger one). A mini fridge, a fermentation chamber (homebrew, set for temp in the 60's sometimes but sometimes used as another refrigerator). A trailer refrigerator (wife won't let me turn it off since she needs the space). and an Electric water heater, and a computer always on for par of our security system and file server etc. We used about $25 of power yesterday

Free supercharger use is the ticket during air season. Still think staying in nem1 is the ticket. Sdge would love to get rid of all the nem 1 customers because we cost them money. More panels is the answer while we still get 30% tax credit. Sdge rates going up 28% over next 4 years. God help those that don’t have solar.

I decided Staying NEM1 plan isn't going to work for me and just submitted a request to try the EV TOU 5 plan.
I was told I can add maybe 6 more panels to my current system and I probably will.

I can switch back to tiered NEM1 plan after a year if this does not work out.

If you add more panels you will be forced into a NEM2 plan anyways.

Details for EV TOU 5 plan are currently as follows:

 

[Dave EV]

Solar will be generating most of its power worth 24-28c kWh (slightly less on weekends and holidays when super-off-peak runs to 2pm). Let's just assume 24c / kWh on average to get a ballpark figure.

1kW of solar will generate 1400-1500 kWh/year in San Diego. Take the low end and it generates $336 worth of energy a year.

Even if it costs a relatively high $4/watt to install, 1 kW costs $4,000, subtract 30% ITC and you get a simple paypack of just over 8 years.

If your loan extends this significantly, then you have to find a loan with a better rate.

SDG&E let's me estimate my annual cost on all plans including the EV-TOU plans. EV-TOU5 is currently the cheapest for me, EV-TOU2 or DR-SES (effectively the same plans), are second cheapest because I only generate about half of my total usage via solar.

 

[EscoguyS75]

Well thanks to EVTOU5, we likely won't have an electric bill going forward.
We have a Model S and and a Model 3. Annual mileage about 30,000. Annual power use is 11,800 kWh at Super off peak which includes a pool pump. Our annual solar production gives us about 9,000 kWh overproduction during peak/off peak hours. 14,500 Gross less 5,500 on peak an off peak use.
Kinda wish I'd known this before I added the third set of panels. I guess I can put them on one of the rentals if I'm really at a negative $1300 use.

Unless I'm missing something, EVTOU5 is a real game changer in a positive way.

 

[Glamisduner]

Well thanks to EVTOU5, we likely won't have an electric bill going forward.
We have a Model S and and a Model 3. Annual mileage about 30,000. Annual power use is 11,800 kWh at Super off peak which includes a pool pump. Our annual solar production gives us about 9,000 kWh overproduction during peak/off peak hours. 14,500 Gross less 5,500 on peak an off peak use.
Kinda wish I'd known this before I added the third set of panels. I guess I can put them on one of the rentals if I'm really at a negative $1300 use.

Unless I'm missing something, EVTOU5 is a real game changer in a positive way.

There has to be a catch right? Don't worry if it's too good to be true SDG&E will change it. Also keep in mind on weekends your generating at 9 cents a KwH then buying power back for 54 cents a KwH from 4-9:00 So. Still I think over all it will save.

Solar will be generating most of its power worth 24-28c kWh (slightly less on weekends and holidays when super-off-peak runs to 2pm). Let's just assume 24c / kWh on average to get a ballpark figure.

1kW of solar will generate 1400-1500 kWh/year in San Diego. Take the low end and it generates $336 worth of energy a year.

Even if it costs a relatively high $4/watt to install, 1 kW costs $4,000, subtract 30% ITC and you get a simple paypack of just over 8 years.

If your loan extends this significantly, then you have to find a loan with a better rate.

SDG&E let's me estimate my annual cost on all plans including the EV-TOU plans. EV-TOU5 is currently the cheapest for me, EV-TOU2 or DR-SES (effectively the same plans), are second cheapest because I only generate about half of my total usage via solar.

Yea our solar loan is a 15 year home equity loan. Back when we got solar the solar specif loans had pretty high rates so the loan I got was the cheapest I could find at the time. If we made it an 8 year loan we would have been paying more than our electric bill was costing us, and that's a hard sell. Still it's saved us a ton of money over the last 5 year if I look at what we would have been paying SDG&E. So I know many people tell me I'm stupid for taking out home equity loan for the panels but it was either a tax decudcable $250 a month + $100 power bill. Plus new windows and new electrical panel and the ability to run AC. or pay SDG&E $450 with no AC or anything. Plus that was 5 yeas ago, I'd probably be paying well over $800 a month by now.

Also SDG&E said I would only be able to see estimates for EV plans after I switched to one. I don't understand why but they said it's because they don't know you have an EV until you switch. But that's kind of funny because they gave me a $500 EV Credit months ago!

 

[Dave EV]

There has to be a catch right? Don't worry if it's too good to be true SDG&E will change it. Also keep in mind on weekends your generating at 9 cents a KwH then buying power back for 54 cents a KwH from 4-9:00 So. Still I think over all it will save.

The catch with EV-TOU-5 is that your minimum bill is $16/mo or $192/yr, even if you end up with a negative bill. EV-TOU-2 has a minimum of $0.329/day or about $10/mo or about $120/yr.

Unless you generate more energy annually than you consume, EV-TOU-5 will usually be cheaper despite the higher minimum bill.

 

[EscoguyS75]

I was in that odd spot where I generated about 85-90% of my annual consumption but over 60% of my net consumption was at night for EV charging and our pool pump.

So the relative shift in prices benefited me with a 59% cut in the night rate. If on the other hand, your night usage is very low and your day usage is high, then the math may not add up. I suspect for most EV drivers, however the lower night rate will offset the costs of the higher day rate.

 

[bomquito]

I’m on TOU-A with SCE. I had my solar system for a year and just got a check for $32 on a -$2100 credits I net the previous year. Can someone explain the difference between NEM 1.0 vs 2.0? I have a 9.1kw system. I’m already negative 500 KWH for the first month with my model 3. Should I be concerned?

 

[Daniel in SD]

You can see appliance use once our solar stops producing. Under 500 watts which may seem like allot, but I have a Kegerator, a refrigerator (it needs to be replaced, but

If I’m reading that correctly you’re using 2kw (maybe 3kw, those bars are 15 minute increments) in the middle of the night! Are you sure your neighbor isn’t stealing your electricity to run a grow house?