Near enough! Although the reality may be that the poles and wires and transformers are not a concern. They will happily send power in either direction up to their full load rating without a hiccup.
For the more local distribution. The tap changing equipment/settings, the ability to control/direct the flows of power back into the grid, and some fault protection requirements are the areas that may most need to be considered. The response of the local networks to sudden shifts in loading (import vs export) due to cloud and weather effects may also require distribution configuration changes and control directly of local feeders.
Most local street level distribution utilises fixed tap changes ( voltage step down ratios) that work fine for steady loads of power flow in one direction only. The ratios need to constantly change as the load decreases or reverses flow and net feedin occurs. this is when local PV generation on a line increases to meet the total load demand from non PV connected properties on the same line.
One interesting solution that would minimise network upgrades may be to mandate battery storage with a percentage of PV installs. Would it be better to subsidise batteries rather than add more gold to the network (HV distribution excluded)? A second step would be to have controlled export from each household system. A variation on this would be for community battery storage attached to local distribution nodes which would still enable household export with less complexity of management?
The issues around the capacity of the national transmission grid are very different from those in the local networks. The national grid has morphed over time to match where the generation capacity has been built and match where the demand is. Adding more pumped storage or wind or solar or hydro export is no different to building a new coal fired power station and needing to upgrade the HV grid to send the extra power to the network. Any discussion that appends this issue as due to household PV generation or unique to renewables is less than reliable.
