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Do you have enough solar to go off grid in winter?

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This is February
 

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Time to get a couple Tesla Powerpacks man. 2x 232 kWh storage = no more NEM.

Errrr maybe you need 5x Powerpacks.
This person is asking the wrong question. As others have stated, the goal should be for 12 months, net zero. So you put it in the PGE bank during the summer, and you take it out of the PGE bank during the winter, that is what I do. I just put in too much during the summer.

Supposed to start getting wiring put my my garage tomorrow for 5 EV chargers. If they can install, and if I buy some of the charges, I really would like to give friends free EV charging. Why not.
 
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I can do it, but with an *asterisk
(system specs in my sig)

My answers assume Dec, which is usually our lowest solar month.

*1 - can't charge the cars unless the sun is shining
*2 - we use natural gas for heating (don't burn me in effigy, it's what the house came with)


In summer, we have such a surplus we don't know what to do with it.
 
So i have 56 panels on my pole barn, and 2 LG packs in my garage (non operational at the moment due to a failed battery) but we're all electric now. 4800 sq ft and charge my Model S and wife's pacifica hybrid. I've now got the whole house switched over to electric including 2 Ground Source Heat Pumps, 2 heat pump water heaters, and all electric kitchen. The only thing that isn't electric is our pellet stove for backup heat in the winter and that's on my critical loads panel for the solar + batteries. Our net metering is quite even at the moment. Through the winter we were close and this is in Kansas so we had some snow. We would need a few more batteries and we could definately do it year round. When i ran off batteries only and no grid through the night early in the system i could make it till about 3 AM. There's no reason this can't be done. And our system payment is just a replacement of our electric bill. I could easily get this much better by sealing up the house better and plan on doing that more. Here's April for example and this has some heating and cooling in it as well as we've had crazy weather here:
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Also last April we had much more reasonable weather and the chart below is from that, 2x export than import. I also did my alignment so that it was max at 2PM and got more later in the day due to stupid demand fees that we had in place when I designed the pole barn orientation to support it. So our system could be putting more out definately and with maybe 2 or 3 powerwalls added we could be in the "off-grid" realm. I don't see where a more typical house (2400 sq ft) wouldn't be able to do this. We have 5 kids so please don't give me too hard a time about the size of the home.

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If I had the $ and didn't live in the Northeast with crazy code requirements I'd build one of these and put a lot of solar on it. Definitely possible:


Put alas I have a split level ranch that guzzles natural gas for heat. I did install a nice Hearthstone soapstone wood stove and that has kept my Winter heating bills under $300 a month...
 
*Could* I go off grid? Yeah, but it in the winter, it wouldn't be pretty at night when it can get in the 20's at times.
This month, I've been averaging a net exporting of just over 18kWh per day, and that's with 5 very cloudy days. I did have one day this month where I had a net import of 2kWh.
I only got PTO back in early April, so I don't know what my winter situation will be like yet.
 
I totally agree. A properly sized system returns a Zero NEM payment at True Up. Anything more is not going to get any ROI unless someone is planning adding EV or some other big usage in the future.

I'll be totally transparent here. Someone on another forum said that they are 100% independent from PG&E (although they are still connected to the grid. I challenged them as I said it would have to be a very big, very expensive solar/battery system to achieve that. They insist they are, but refuse to give specifics, although he did mention Enphase.

Here's his post:
"I got 100% Independant from PG&E and it’s costing way less per month. Don’t have to deal with power outages either. Costs nothing to do it. Message me if you’d like help."


If I were to do this TODAY, I'd need a generator hooked up to recharge the batteries (available on Enphase system currently) on only cloudy/rainy days before evening. I'm not sure how long generators last though and that's the beauty of solar panels, no moving parts.

I'm on Enphase storage and have 20kWh storage. It'll cut out the IOU, but I still have a gas line so I'd be dependent on them for that unless I find some whole house electric heaters or maybe, like my earlier posts, some type of massive propane tank like I used to see in Tahoe winter homes.

In my own case, I live in So Cal so we get a ton more sun here. We use < 20khW per day so consumption is pretty low (and this is with being home all day/night due to WFH). The winter wasn't that bad for me honestly since we usually can get some sun the next day and it takes us about 3 hours to charge the batteries to full from like 40-50%. I'd up the storage to 40kWh (to avoid having to cycle the generator) if I were to completely go off grid.

Cutting the gas line for us would be personally harder due to water/heat/stoves are all gas. We have an EV, but was living on L1 charging since forever and the solar alone takes care of that since we WFH and rarely ever drive.
 
I totally agree. A properly sized system returns a Zero NEM payment at True Up. Anything more is not going to get any ROI unless someone is planning adding EV or some other big usage in the future.

I'll be totally transparent here. Someone on another forum said that they are 100% independent from PG&E (although they are still connected to the grid. I challenged them as I said it would have to be a very big, very expensive solar/battery system to achieve that. They insist they are, but refuse to give specifics, although he did mention Enphase.

Here's his post:
"I got 100% Independant from PG&E and it’s costing way less per month. Don’t have to deal with power outages either. Costs nothing to do it. Message me if you’d like help."
This is not necessarily true for some people, especially when one's summer use is many times more than that of their winter use, such as in my case. Sizing the system to meet our summer AC and pool pump with the excess summer sun means that the much less sun winter sun will not have as much affect because the two things (pool and AC) that when combined use can sometimes use over 3x's the energy as the rest of the house and are not used in the winter (pool just ran for a couple of hours on really low RPM.)

We will produce over 40 kWh of solar during the summer on the best days and use about the same (sometimes more on really hot days where the AC is running a lot). We will produce up to 20 kWh on the best winter days and seldom use more than that in the winter (if we do it is just by a couple kWh.) Sometimes we may even use less than 10 kWh in the winter, but most often between 15-20 kWh. All of our appliance are gas. Even the central heating furnace using an electric blower only runs for a few minutes as a very efficient gas heater can heat the house a few degrees within a few minutes. The few days we have to run it, we only do so early in the morning.
 
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I live in CA and have been off grid now since October without interruptions. Winter is no problem. I have 14 kw solar and 4 powerwalls. House is 4200 feet, 3 ac units, 2 EV's electric dryer, electric oven and stove. rest is propane. I'm waiting for Tesla to improve the powerwall software before I cut the cord.

The biggest drain is the car charging. The newer Tesla's manage the charging pretty well limiting the charging to a set limit of the powerwalls state of charge. I wish the cars stayed awake when this is activated and polled the powerwalls to start charging when the state of charge is reached to allow charging is achieved. As it is now, you have to wake the car to activate charging. The car should then allow a full sleep once the car is fully charged.
 
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You've got to have batteries to make solar work. I've got 66 solar panels (7 kwh), but only 3 power walls. Wish I had 3 more, because 3 power walls only give me 20 kwh or less of power storage., not nearly enough to charge one car, much less two. Of course, I have to realize that charging one car uses more electricity than my house uses in a week but charging the car a tiny bit each night is a pain.
 
Energy costs money, no matter how you manage it. Utilities bill, Solar costs, insulation costs, batteries cost, generators cost, window blinds cost, fuel storage cost, etc.

Every homeowner will make individual decisions on how to best manage their energy usage. As things change, the home must also be flexible to adapt to new realities.

In my case the installation of a quiet cool fan, combined with insulated window coverings, can significantly reduce my home energy usage. These cost as well, but have far quicker paybacks than Solar.
 
You've got to have batteries to make solar work. I've got 66 solar panels (7 kwh), but only 3 power walls. Wish I had 3 more, because 3 power walls only give me 20 kwh or less of power storage., not nearly enough to charge one car, much less two. Of course, I have to realize that charging one car uses more electricity than my house uses in a week but charging the car a tiny bit each night is a pain.

I think it's actually less about # of power walls, but actually getting another power source. Solar/storage is not enough for say, a week of cloudy weather or for anyone in CA, a crazy wildfire blocking all sun with smoke. For charging your car, you can also stop by a Tesla Supercharger if you really needed it.

Everyone will merely adjust if we were forced to cut the cord and for some of us, it'll be easier than others. Also, if you know there are clouds for the next 3+ days, you'll adjust your plan and maybe drive less, not use the dryer/stove as much, or just refill the gas/diesel generator and fire them up anyways.