For development proposals that require a planning permit this is assessed on a case by case basis by the relevant planning authority, with reference to planning scheme standard A7 and B10 under Clauses 54.03-5 and 55.03-5 Energy efficiency protection objectives.
Where the development only needs a building permit, comparable setbacks apply.
If the Calculator estimates a set back angle greater than 58.8 degrees (or over 47.5 degrees where there is a north facing window – and the solar panels are located above the window) then more detailed assessments by the council planner or building surveyor may be necessary to check that the required setbacks are being achieved. The tool provides an estimate only as it is limited by the fixed number of standoff distances that can be selected.
Planning system standards covering overshadowing of rooftop solar systems are outlined under Clauses 54.03-5 and 55.03-5.
Standard A7 and B10 specify (in part) that new buildings should be:
'Sited and designed to ensure that the performance of existing rooftop solar energy facilities on dwellings on adjoining lots in a General Residential Zone, Neighbourhood Residential Zone or Township Zone are not unreasonably reduced. The existing rooftop solar energy facility must exist at the date the application is lodged'
This also applies to overshadowing from buildings at zone boundaries (e.g. in a commercial zone) where the shadows are cast on existing solar systems in these residential zones.
Generally, a development should be designed to ensure at least 70% of annual solar energy generation of an existing system is maintained. After considering the other factors listed in this clause and the planning scheme, design measures should be applied to achieve better outcomes and reduced energy generation losses due to overshadowing,
Page last updated: 22/11/19