tripzero
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I have a 3KW system on my roof. On a good day, it'll do over 2.5KW. My AC system is at least that much and with all the random electronics, I don't have much to spare. The mobile charger can do 12A on a 120V Nema 5-15 for a total of 1.4KW. This is quite a big load doing pure solar and my smart switches (that turn only when there's available solar power), would constantly turn off whenever AC kicked on or a cloud rolled over. This made charging during the day a challenge. To make matters worse, I estimate the vampire drain of the cybertruck with cabin protection and sentry to be somewhere close to 800W. When I had set the cybertruck down to 800W charging via solar to keep it within solar budget, it actually lost charge.
The most consistent charging comes at night with sentry mode off, but it's still very slow at just 1KW (trying not to overload that circuit as it's shared with other things).
So how do I charge via solar when it's available, without having to drop the charging speed so low?
Powershare gateway with the universal wall connector doesn't solve this. The wall charger would charge at power rates that would exceed any solar I'm producing. On top of this it's a $4k install (quoted). With very infrequent power losses and no ability to grid-tie the truck to the home, there's not a lot of value there. So I started looking around.
If you can find a deal, home "portable" batteries have an return on investment of as low as 8 years. In the worst case it's 15. These are preferable to a powerwall because they do not require expensive installation costs. So the idea is to charge up a sizable battery during peak solar hours (even if it's less that 800W) and then use that to charge the cybertruck at night. I calculated I use about 5KWh driving to work and back, so I'd need about that size of a battery for daily use.
Enter the AC300. This is a 3KWh battery that can output 3KW with a TT-30, 30A plug. I think with the right adapter, the cybertruck will charge at up to 24A over 120V. The battery is expandable up to 12KWh or 24KWh when tethered to a second AC300. Also when tethered, it can provide 240V 30A. I figured YOLO and bought an AC300 and two expansion batteries (6kWh total) for about $3k on sale. The AC300 has two MPPT controllers for up to 2400W direct solar charging plus it can charge up to 3KW from the grid. I figure for the remaining $1K I can build a 1200W solar canopy and run a line to this battery. Room to expand later.
Potential problems and solutions:
First, what happens if I need to charge more than 6KWh? Won't the battery die? I do have time of use, so at night I will be simultaneously charging the battery and the cybertruck (likely 1KW in and 2.9KW out). That should give it a theoretical 9KWh of total charge power before the battery shuts the load off. We can always expand the battery later as needed.
Can we actually charge up the battery during the day with solar?
I have a budget of 20KWh on "good" days. There's not much to spare. I will likely need to expand with a small solar canopy over my deck. I estimate it'll cost about $1000 for 3x400W panels, the wood/hardware and 100ft of 10AWG cable.
What about when the sun doesn't shine?
We'll always have some power, even if it's only a little. The winter months are going to be brutal, but in the worst case, I charge the truck a bit slower from the grid and don't save as much money.
Why not the powerwall?
The powerwall's hardware price is hard to beat. 13.5KWh for just $8k is awesome. The payoff is the shortest of any of these "portable" or home batteries outside of DIY. The kicker is the installation costs (assuming $7000). It pushes that 8 year payoff to 20 years.
Additional benefits:
It's not the $16k expanded battery pack, but I figure it could help in a jam if you take this portable battery system with you camping or whatever. 12KWh will give you an extra 20 miles or so. It'll also take up less room in the bed and you can remove it when not needed. In addition, the cybertruck roof has over 700W of solar PV space (2.7432m x 1.8288m = 5m^2 * 800W * 17%). These batteries can also power the house and can be charged with the cybertruck.
Summary:
The up-front cost of this system is less than the $2400 (hardware) + $4000 (install) powershare cost and much more flexible. It's portable, can power my home (minus the AC), can charge via solar, the grid or the truck. This solution is also more flexible and cheaper than the powerwall (although, doesn't have the grid-tie capabilities). Now I can use that delicious $2400 credit for other goodies in the store.
The most consistent charging comes at night with sentry mode off, but it's still very slow at just 1KW (trying not to overload that circuit as it's shared with other things).
So how do I charge via solar when it's available, without having to drop the charging speed so low?
Powershare gateway with the universal wall connector doesn't solve this. The wall charger would charge at power rates that would exceed any solar I'm producing. On top of this it's a $4k install (quoted). With very infrequent power losses and no ability to grid-tie the truck to the home, there's not a lot of value there. So I started looking around.
If you can find a deal, home "portable" batteries have an return on investment of as low as 8 years. In the worst case it's 15. These are preferable to a powerwall because they do not require expensive installation costs. So the idea is to charge up a sizable battery during peak solar hours (even if it's less that 800W) and then use that to charge the cybertruck at night. I calculated I use about 5KWh driving to work and back, so I'd need about that size of a battery for daily use.
Enter the AC300. This is a 3KWh battery that can output 3KW with a TT-30, 30A plug. I think with the right adapter, the cybertruck will charge at up to 24A over 120V. The battery is expandable up to 12KWh or 24KWh when tethered to a second AC300. Also when tethered, it can provide 240V 30A. I figured YOLO and bought an AC300 and two expansion batteries (6kWh total) for about $3k on sale. The AC300 has two MPPT controllers for up to 2400W direct solar charging plus it can charge up to 3KW from the grid. I figure for the remaining $1K I can build a 1200W solar canopy and run a line to this battery. Room to expand later.
Potential problems and solutions:
First, what happens if I need to charge more than 6KWh? Won't the battery die? I do have time of use, so at night I will be simultaneously charging the battery and the cybertruck (likely 1KW in and 2.9KW out). That should give it a theoretical 9KWh of total charge power before the battery shuts the load off. We can always expand the battery later as needed.
Can we actually charge up the battery during the day with solar?
I have a budget of 20KWh on "good" days. There's not much to spare. I will likely need to expand with a small solar canopy over my deck. I estimate it'll cost about $1000 for 3x400W panels, the wood/hardware and 100ft of 10AWG cable.
What about when the sun doesn't shine?
We'll always have some power, even if it's only a little. The winter months are going to be brutal, but in the worst case, I charge the truck a bit slower from the grid and don't save as much money.
Why not the powerwall?
The powerwall's hardware price is hard to beat. 13.5KWh for just $8k is awesome. The payoff is the shortest of any of these "portable" or home batteries outside of DIY. The kicker is the installation costs (assuming $7000). It pushes that 8 year payoff to 20 years.
Additional benefits:
It's not the $16k expanded battery pack, but I figure it could help in a jam if you take this portable battery system with you camping or whatever. 12KWh will give you an extra 20 miles or so. It'll also take up less room in the bed and you can remove it when not needed. In addition, the cybertruck roof has over 700W of solar PV space (2.7432m x 1.8288m = 5m^2 * 800W * 17%). These batteries can also power the house and can be charged with the cybertruck.
Summary:
The up-front cost of this system is less than the $2400 (hardware) + $4000 (install) powershare cost and much more flexible. It's portable, can power my home (minus the AC), can charge via solar, the grid or the truck. This solution is also more flexible and cheaper than the powerwall (although, doesn't have the grid-tie capabilities). Now I can use that delicious $2400 credit for other goodies in the store.
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