My idea is to ensure that all buildings become carbon neutral in terms of long term energy use.

When money is available to build a building or make significant renovations, the cost of putting solar panels on the roof to approximately off set the long term energy use of the building is generally negligible in comparison to the cost of the total works. This requirement to install solar panels on new/renovated builds should be legislated through the Building Code of Australia and possibly "incentivised" through interest free loans to the applicant or reduction in some tax or other duty normally paid during the development process.

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