VRB's can be installed in new developments as far as GRID...

VRB's can be installed in new developments as far as GRID stabilization and bulk storage. so far they are too expensive and bulky for the average punter, But If the power company/developer are smart they can install the VRB(s) next to the new transformer for the development.
That way you can sell back to the GRID when you want to rather than selling the excess generated during the day once the powerwalls are at 80% and the feed in tarif is low.
Also The VRB's kick arse on diesel gensets due to neglible maintence and no diesel to purchase and truck in, which in WA is the biggest part of the diesel pump price after Tax/excise.
Also helps for a construction cost as you dont have to have a Fire rated bunker and fire management plan for your backup power.
other thing to consider is the Green star rating you can get from the development which opens up the abililty for grants and finance discounts for sustaiablilty, most people forget that australians will pay for the green option if it saves them money medium term.
New Builds in NSW now must come with the BASIX green certificate showing the performance of the house and costs of running the dwelling into the future. you can also ask for one during purchase of existing properties to guage the performance of the existing dwelling vs knock down and rebuild to current code.

Makes a very good marketing pitch for your sales team if you can demonstrate that the house you build will cost half to a quarter less to run than the place down the road.