AndyH wrote:Nothing complex about this stuff at all.
That's a technologically privileged view. Home solar is great for hobbyists and nerds and that's what needs to change. IMO Tesla didn't go far enough here to create an offering with mainstream appeal.
With respect, LTLFT, I'm on record throughout this forum suggesting that one that buys PV and an inverter ONLY capable of being grid-tied is buying half a system. This was validated in a number of threads where other members complained in surprise when they realized only after they wrote the big check that their green electricity would drop off-line when the grid fails.
There are grid-tied/grid-interactive inverters today
that can not only do the PV-grid side of the job, but can also charge a battery, and act as the 'generator automatic transfer switch' in the event of a grid failure - so all the critical pieces/tech/knowledge already exists. The only thing that might be missing is the ability to handle a 400V battery rather than a more typical 24 or 48VDC pack, but as that's a typical grid-tied PV voltage level, I expect the 'plug and play' inverter for residential users is already in the works.
Finally, I think that Musk had to omit the inverter part right now (if in fact he did) as, thinking ahead, he apparently intends that the battery will be part of a future smart grid that allows for bi-directional use the w
ay a V2G car battery can be used for grid storage, frequency stabilization, etc. I don't know of any widespread use of that in the US yet outside of utility-scale storage, so he's deploying the 'big pieces' that can be upgraded once the rest of the grid is ready.
If you want to know more about the tech details, ping Reg or GRA - I believe they've both installed on- and off-grid PV systems.