Simpliphi Lithium batteries and Enphase system.

[carsantini]

Existing solar system is compose of Enphase micros and 370w modules. What is the best (cost/effective) battery alternative for my system? PW2 or Simpliphi Lithium bats? Acid based battery are not allow in my location.

[Mike90250]

What location allows Li but not SLA/AGM ? Airplanes sure don't

[carsantini]

Building regulations in my location. I dont know why but absolutely have no interest in changing or fighting this policy with the Board of Directors.

[jflorey2]

Existing solar system is compose of Enphase micros and 370w modules. What is the best (cost/effective) battery alternative for my system? PW2 or Simpliphi Lithium bats? Acid based battery are not allow in my location.

As you probably know, Enphase now has "AC batteries" that are compatible with Enphase inverters, but they are insanely expensive - ~$2000 for a 1.2kwhr, 270 watt output battery.

SimpliPhi is a bit cheaper - $3K for 3.5kwhr - but of course you need to add an inverter and it is NOT easy to get most inverters to play nice with a microinverter array. Also per rumors at SPI they are having reliability problems.

Powerwall is $5500 for 13.5kwhr which of course is far cheaper than all the above, and contains the inverter already. But they are hard to get; I haven't seen one anywhere in San Diego yet.

If you roll your own with cheap CALB-type cells you are looking at $4000 for 9kwhr for just the battery - and now you need an inverter, wiring and safety equipment and a BMS.



Are you looking to do this for standalone operation, peak shifting/power arbitrage or just for backup?

[carsantini]

jflorey2 thks for the info. I want the batteries for backup and to provide energy at night until the sun rises again. No interest on sending energy to the grid because here in Puerto Rico after hurricane Maria blackouts are the norm, its a mess.

[ButchDeal]

jflorey2 thks for the info. I want the batteries for backup and to provide energy at night until the sun rises again. No interest on sending energy to the grid because here in Puerto Rico after hurricane Maria blackouts are the norm, its a mess.

What you really want is the backup capability.
You do However want to use the net metering and feed power back to the grid. The grid stores power for you at 100% efficiency. This will extend the life of the batteries as well as keep them as fresh as possible for the best backup capabilities.
This is called bimodal or hybrid system.

You likely also want to stay away from the enphase battery solution as it does not provide backup capability, just load shifting.

You stated that Acid based batteries are not allowed at your location, does that go for SLA/AGM as well? That makes no since since SLA are considerably safer than Li.

If so then you do have an option of the LG RESU10 or RESU10H
The RESU10 is a 48V version and would work well with an OutBack inverter which can easily AC couple with your enphase micros and control them.

[adoublee]

Building regulations in my location. I dont know why

Probably knee-jerk reaction to addressing hydrogen off-gas concerns.

[ButchDeal]

Probably knee-jerk reaction to addressing hydrogen off-gas concerns.

so you couldn't even have a UPS for your computer:

https://www.amazon.com/APC-Compact-Protector-Back-UPS-BX1000M/dp/B06VY12HW4/ref=sr_1_1_sspa?ie=UTF8&qid=1520435055&sr=8-1-spons&keywords=ups+battery+backup+%26+surge+protector&psc=1

[adoublee]

so you couldn't even have a UPS for your computer:
https://www.amazon.com/APC-Compact-P...rotector&psc=1

I suppose he could ask if he feels he must, though using a computer UPS is going to be a lot less obvious than having your residence powered when the grid is down.

[ButchDeal]

I suppose he could ask if he feels he must, though using a computer UPS is going to be a lot less obvious than having your residence powered when the grid is down.

my point is that they are considered safe with zero venting in occupied spaces.

[adoublee]

my point is that they are considered safe with zero venting in occupied spaces.

The International Fire Code is one reference for regulation on ventilation of rooms with VRLA batteries, independent of what someone considers safe. Li-Ion are exempted from ventilation beyond that normally required for human occupancy. The building owner may not want to be responsible for ensuring the limit on hydrogen concentration. Not my battle, just a potential reality for the OP.

[ButchDeal]

The International Fire Code is one reference for regulation on ventilation of rooms with VRLA batteries, independent of what someone considers safe. Li-Ion are exempted from ventilation beyond that normally required for human occupancy. The building owner may not want to be responsible for ensuring the limit on hydrogen concentration. Not my battle, just a potential reality for the OP.

If you are talking about section 608, that specifically states for "an electrolyte capacity of more than 50 gallons....or more than 1,000 pounds (454 kg) for lithium-ion and lithium metal polymer"

That would be a pretty big battery at 50 gallons for a residential system.

[adoublee]

If you are talking about section 608, that specifically states for "an electrolyte capacity of more than 50 gallons....or more than 1,000 pounds (454 kg) for lithium-ion and lithium metal polymer"

That would be a pretty big battery at 50 gallons for a residential system.

Your point that "they are considered safe with zero venting in occupied spaces" is an overly presumptuous statement even though I know you are extremely confident in your opinions. That section of IBC in particular may not apply, but it is a minimum standard and points out a valid concern with unrestricted tenant VRLA installations whether you feel a restriction is warranted or not. There are concens with VRLA that don't apply to Li-Ioin, even if Li-Ion may be more hazardous for different reasons the building owner has't yet taken concern with.

Best of luck to you in Puerto Rico carsantini!