sfsuphysics
Supporting Member
but house can fit more tanks eh? 
Electricity Use
- Thread starter ddrueckh
- Start date
ashburn2k
Supporting Member
sfsuphysics
Supporting Member
but with another roof means more tanks that can fit under that roof
Wlachnit
Past President
I have seen some available space in his kitchen..can easily fit a couple more tanks.but house can fit more tanks eh?
Flagg37
Guest
I always thought bathroom tanks were cool too.
scuba71
Supporting Member
Get Tesla batteries... it will help offset if you cannot get more panels.
I have an 7.5Kw system with two 20kw batteries.
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sfsuphysics
Supporting Member
The Tesla one I think is about $7k or so for 13.5kWh of storage, and that's the base price, not the installed price. Getting an electrician to install the appropriate equipment to make it legal might cost another grand, I dunno what their rates are really.
iani
Supporting Member
How does that work? Something to do with time of use?
Flagg37
Guest
Yes, but if there’s no excess power going to the battery because it’s all used up then it doesn’t do any good.
RandyC
Supporting Member
That's assuming the tanks don't take up all the juice, but yeah, if you weren't tapping 100% of the solar generation during the day, you'd have some stored for the night.
For example, here's my graph for today. I probably could have come close to filling up a third of a 13.5kWh battery. Not bad for a winter day.
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Coral reefer
Past President
I am jealous!
iani
Supporting Member
But with net metering doesn't that not matter? My excess power gets fed back into the grid. Which I get credit for and can use later.
RandyC
Supporting Member
Not all power is created equal in price. I believe that Powerwall users (without solar) have the ability to control when to feed the power back to the grid, so you charge at night at cheap rates and feed it back at peak rates (for those on Time of Use (TOU) plans, like EV-A or EV-B plans). Those with solar and powerwall don't have that option now, but apparently it's coming soon.
Also, it can help potentially avoid getting charged at peak TOU rates if you can generate enough excess during off-peak times (midnight-3pm) to store in a powerwall to get you through peak times (3-9pm).
sfsuphysics
Supporting Member
Ian, you have an older solar system so PG&E just runs your meter backwards and you do get a 1 to 1 credit for power not used. Now if you hook up power PG&E will force you into some ToU schedule partially because solar makes power at a time when power demand is fairly low, second they can make so much more money getting people on ToU schedules.
If the software could do it, not sure as I don't own a power wall, you could sell back at a higher rate, and technically you could "fill up" at the low off-peak rates and sell back at higher "peak" rates, but there definitely would be losses in storage and pushing back so who knows if you could actually make out profitable there.
Bottom line is PG&E's ToU plans are so varied it's hard to determine which ones you can get, or will get if you switched over, the EV ToU plan seems really nice if you could in fact store energy at night and sell it back later, but if you use energy during "peak time" you are going to be paying for ALL your power at rates that are more expensive than the >400% baseline tier.
That said California had (has?) some incentives now for Powerwall, like BIG TIME incentives, not sure about all the details though, I think the purposefully make shit complicated so homeowners have to get qualified installers (which can triple the cost in some cases). But I think when it first came out Tesla Powerwalls were practically free with the rebates... needless to say the first step for it all got swiped up almost instantly... which again sucks for homeowners, great for businesses who employ their own inhouse electricians.
If the software could do it, not sure as I don't own a power wall, you could sell back at a higher rate, and technically you could "fill up" at the low off-peak rates and sell back at higher "peak" rates, but there definitely would be losses in storage and pushing back so who knows if you could actually make out profitable there.
Bottom line is PG&E's ToU plans are so varied it's hard to determine which ones you can get, or will get if you switched over, the EV ToU plan seems really nice if you could in fact store energy at night and sell it back later, but if you use energy during "peak time" you are going to be paying for ALL your power at rates that are more expensive than the >400% baseline tier.
That said California had (has?) some incentives now for Powerwall, like BIG TIME incentives, not sure about all the details though, I think the purposefully make shit complicated so homeowners have to get qualified installers (which can triple the cost in some cases). But I think when it first came out Tesla Powerwalls were practically free with the rebates... needless to say the first step for it all got swiped up almost instantly... which again sucks for homeowners, great for businesses who employ their own inhouse electricians.
sfsuphysics
Supporting Member
Was it a cloudy day? I'm assuming each of those bar widths represents an hour. Because at 6.9 kW system you mentioned I would think those green bars should be much higher on the graph around noon time.
RandyC
Supporting Member
Yeah, I think there were clouds yesterday.
Here's a typical sunny summer day for me.
