If we assume the old chart about the capacity bars is still correct it's more like 66% or if we assume that SOH represents the capacity it's more like 62-65%.RegGuheert wrote: That's a bit better than the LEAF's battery capacity warranty since it guarantees 72% at five years (and Tesla's goes to ten).
Andy Palmer confirmed at the Saturday August 24, 2013 Phoenix dinner that the service manual chart was correct.QueenBee wrote:If we assume the old chart about the capacity bars is still correct it's more like 66% or if we assume that SOH represents the capacity it's more like 62-65%.RegGuheert wrote: That's a bit better than the LEAF's battery capacity warranty since it guarantees 72% at five years (and Tesla's goes to ten).
As you can see, they have doubled the usable energy and nearly quadrupled the power capability. Price is now 1/2 the price of the Enphase AC Battery on a per-kWh basis (but that is in Elon-dollars, which are often quite a bit lower than real dollars). Frankly, this product looks significantly more attractive than the previous version.Tesla wrote: Usable Capacity
Depth of Discharge
7kW peak / 5kW continuous
Solar self-consumption Time of use load shifting Backup Off grid
Up to 9 Powerwalls
-4° to 122°F / -20°C to 50°C
L x W x D: 44" x 29" x 5.5" (1150mm x 755mm x 155mm)
264.4 lb / 120 kg
Floor or wall mounted Indoor or outdoor
UL and IEC certified Grid code compliant
RegGuheert wrote:It seems the capacity warranty for the Tesla Powerwall still lasts for ten years, but has been reduced to 60% or 18 MWh at that point: Tesla Energy's Incredible Shrinking Powerwall Warranty.
That's a bit better than the LEAF's battery capacity warranty since it guarantees 72% at five years (and Tesla's goes to ten). OTOH, 18 MWh only comes to 2800 full cycles (at the full 6.4 kWh capacity). That warranty pales when compared to the warranty Enphase offers for the AC Battery, which is 80% capacity retention at 10 years or 7300 cycles.
So, let's see how they stack up in terms of US$/kWh (discharge):
- Tesla Energy: US$3500/18,000 kWh = US$0.194/kWh (Assumes Tesla meets their price and excludes the price of the inverter.)
- Enphase Energy: US$1000/(7300*1.2 kWh*0.95*0.9*0.9) = US$1000/6740 kWh = US$0.148/kWh (1.2 kWh, 95% usable capacity, 90% round-trip efficiency, 90% average capacity over life, inverter included, Envoy excluded, assumes all 6740 kWh is used within the cycles OR Enphase bases warranty on total energy discharged, both of which are unlikely)
Of course, the Tesla offering supports off-grid application while the Enphase product is grid-tied only. IMO, Tesla will have difficulty competing with lead-acid in off-grid applications due to price and will likewise have difficulty competing with Enphase for time-shifting grid-tied applications. Elon will need to really talk this this one up to try to get it to sell.
Generally, no. If one wanted to do this, one would probably need to purchase several powerwall batteries, along with lots of solar panels for charging them.mxp wrote:With this battery installed in home, how does the customer disengage from the Grid (i.e. the utility company) and use the battery solely?
The new Powerwall 2.0 batteries include a built-in inverter for connecting to the mains. Along with the software for controlling it, this will automatically choose when to charge and discharge the battery. There will be no user-accessible "switch", other than a breaker (which is not something that a user should be flipping regularly).Will Tesla install some kind of switch for end-user to engage or dis-engage from utility grid/battery ?
Indeed, that's how most owners make use of the powerwall. In addition, it provides a whole-house UPS for when the power goes out.Ideally, I would like to charge the battery overnight (low cost) and in the daytime, disengage from the utility grid.
Anytime there is power generation connected to the grid there must be a cut-off switch. You can not have solar or other power sent back through the grid if the power company shuts power down to do maintenance. This switch is included with the powerwall.LTLFTcomposite wrote:So with powerwall 2.0 it sounds like a much more integrated solution. Just add panels?
As for backup, wouldn't that require an isolation/transfer switch? I guess since the powerwall would always be connected to the home's internal wiring (service panel) it wouldn't be a transfer switch per se, but there does need to be a disconnect to the utility, no?