Coal the loser as power prices smashed Apr 28, 2021 – 12.01am Share Mushrooming rooftop solar and mild summer weather have driven demand for power from the grid to the lowest for 19 years for the peak summer quarter, cutting wholesale prices by up to 68 per cent and pushing major coal and gas power generators such as AGL Energy to the brink. NSW, Victoria and South Australia all had record low demand for power from the centralised grid for the three months of the year when consumption is typically highest and prices the most volatile. The installation of rooftop solar panels hit a fresh high for a March quarter of about 800 megawatts.