My Battery Powered Home
This is an SMA America Sunny Boy SB-5.0-US-41 transformerless inverter. The maximum output power is 5000 watts. It has 2 maximum power point tracking channels to help with complex roof geometries, odd string counts, and shading.
Energy storage system
My home is powered by the sun at night using stored energy from a sonnenCore 10 kWh ESS. It is a fully integrated solution, meaning the lithium ion batteries and power electronics are in one cabinet. I have a protected loads panel with every circuit in my home on it except for my 3 ton AC and my electric dryer. With proper load management, I can have unlimited power to my home during a grid outage.
module level electronics
Beneath each solar module there is a Tigo TS4-A-F MLE used to shutdown the module voltage during an emergency. This is a mandatory requirement in the United States and is referred to as Rapid Shutdown (RSD). I decided to use Tigo since the SMA inverter has a built in transmitter used to keep the Tigo MLE "on". When a first responder shuts off AC power to the inverter, the internal transmitter also shuts off. Without the signal from the transmitter, the MLE will then shut down, isolating all voltage at the module level.
Contrary to common usage, this is not solar "panel". A solar panel heats water but a solar module creates direct current electricity using the sun. I have 16 Jinko 320 watt modules split into two strings, both having 8 modules. Each string is connected to a separate MPPT in the PV inverter. The left side of the array starts to become shaded by my neighbor's tree. The left 8 modules that make up string #1 will not affect the other side of the array when they become shaded. Click the button below to read my blog post for more information on shading.
balance of system
This is the ugly side of solar and storage- all the extra equipment that is required to comply with safety, wire management, labeling, and any dumb thing the electrical inspector wants you to include. Maybe one day the BOS components will look as sexy as the solar and ESS equipment.