> They are focused on giant transmission line projects and hydro

Is that because of the scale they need to achieve to support the investment?

> until I demonstrated that the project would never feed back to the grid

Financial greed aside, and I mentioned this previously, feedback at a large scale isn't free especially if the impedance of the grid cannot be predicted - the frequency or voltage or both would spike. Monitoring for these conditions are expensive and addressing them is even more expensive - the cheapest solution is you do a shutdown until things stabilize but this is kinda catch-22 because that itself might have its own cascading effects.

Let me ask you this - if you were to update a local neighborhood (like a block or two of 1000 homes) distribution station, that all have their own solar and battery, where the homes could independently power themselves for a day - what changes or upgrades would you make to ensure they can share load for that one day when the larger grid is suffering an outage?

Now would that cost and complexity be lower or higher if instead, nothing was changed at grid scale at all but each of the individual 1000 homes doubled their own capacity (let's say 30kWh a day if you're OK with that)?