If the battery has 96% round-trip efficiency and the new S280 Microinverter has 97% one-way efficiency, then the overall round-trip efficiency for the AC Battery comes to 90% (ACout/ACin). This should be slightly higher than the Tesla PowerWall AC/AC efficiency.Enphase AC Battery Brochure wrote:Higher performance
• 96% round-trip efficiency for the battery
• 2 cycles per day delivers twice the value for a faster payback period
10-year warranty is nice! I wonder what the details are.Enphase AC Battery Brochure wrote:Greater reliability
• Lithium iron phosphate chemistry from Eliiy Power for long cycle life
• 10 year warranty
• No single point of failure
95% DOD is very high. Is it really warranted to do that twice each day for 10 years? I doubt it.Enphase AC Battery Brochure wrote:Safer
• Our prismatic cells from Eliiy Power are highly stable over time
• Safety certified by TUV Rheinland
• No high voltage DC in system
• Most usable capacity with greater than 95% depth of discharge
i asked a sales engineer yesterday. All he would say is they know there is a demand and they are working on it. The new inverters are expected to Bo in distribution channels in October. I just got pricing today.wwhitney wrote:So has Enphase said anything about the possibility of using the Enphase Energy Management System to provide an AC-coupled battery backup during grid outages? Is there a provision for a dump load?
Cheers, Wayne
Actually, they have. Here is what Enphase CEO Paul Nahi said recently:wwhitney wrote:So has Enphase said anything about the possibility of using the Enphase Energy Management System to provide an AC-coupled battery backup during grid outages?
Paul Nahi wrote:“Does backup have that much utility? I think backup is being way overblown as a capability. If you really need backup, the problem is, 7kWh, 20kWh isn’t gonna do it. If you really want backup, you get a generator. There are companies that provide natural gas or diesel generators that are very inexpensive, and can truly keep you backed up indefinitely. That’s not to say there isn’t a market for battery backup [but] it’s going to be relatively small.
RegGuheert wrote:Actually, they have. Here is what Enphase CEO Paul Nahi said recently:wwhitney wrote:So has Enphase said anything about the possibility of using the Enphase Energy Management System to provide an AC-coupled battery backup during grid outages?Paul Nahi wrote:“Does backup have that much utility? I think backup is being way overblown as a capability. If you really need backup, the problem is, 7kWh, 20kWh isn’t gonna do it. If you really want backup, you get a generator. There are companies that provide natural gas or diesel generators that are very inexpensive, and can truly keep you backed up indefinitely. That’s not to say there isn’t a market for battery backup [but] it’s going to be relatively small.
I agree. Having some amount of off-grid capability is an important selling feature if you're going to have storage.JimSouCal wrote:As per below, if this vein runs through the company, I'd submit the CEO isn't looking at the tea leaves accurately. I see this as unfortunate for a company seemingly keyed into marketing and buyer behavior.
I've had 2 outages in the last month lasting 30-90 minutes. Would have been nice to have some backup!JimSouCal wrote:Locally (LADWP), we've had several outages
This data makes me wonder whether Enphase' AC Battery will store 1.6k Wh of energy rather than the 1.2 kWh originally indicated. The reason is that each of these cells stores 160 Wh of energy and ten cells in series gives you an overall battery output voltage ranging from 28 V to 36 V, which fits perfectly with the S280's "Peak power tracking voltage" range of 27 V to 37 V. Ten cells would weigh about 33 lbs. Add in 15 lbs. for two S280s, a BMS, wiring and connectors and another 10 lbs. for packaging and you are right around 60 lbs for the unit, which should be manageable.Eliiy Power wrote:Battery Cell Specifications
Nominal capacity: 50 Ah
Nominal voltage: 3.2 V
Weight: 1.5 kg
Size: W 170.5 x D 43.5 x H 111.9 mm
Energy density: 106 Wh/kg
Operating temperature: -20 to 60C (guaranteed operating temperature: 0 to 45C)
Cathode material: Lithium iron phosphate
Anode material: Carbon
Hopefully those numbers are real and include the effects of calendar life as well and not just the cycling.Eliiy Power wrote:What’s more, they offer an extended lifespan: even if charged and recharged repeatedly for 10 years (approx. 12,000 times), they will retain 80.1%* of their electricity storage capacity.
*Estimated value assuming 23ºC room temperature and three full charge and recharge cycles per day (depth of discharge (DOD) = 100%).