(1) The regulations may provide that, if any charge under section 146 remains unpaid by the body or person liable after the time when it became due for payment, the body or person is liable to pay to the Authority, by way of penalty, an amount calculated at the rate of:
(a) 20% per year; or
(b) if the regulations specify a lower percentage--that lower percentage per year;
on the amount unpaid computed from that time.
(2) A penalty under this section may be recovered by the Authority as a debt due to the Authority.