Spot prices may not exceed a cap of AUD 12 900 per MWh. As can be seen, very high prices are rare, with prices sitting within the range of AUD 0-40 for around 90% of the time. Flowever, views differ on the adequacy of high but capped wholesales prices as a sufficient incentive to invest in marginal supply. Reducing carbon emissions associated with power generation is a central challenge in the project to reduce overall emissions from human activity. This is the case not only because stationary energy currently accounts for 40% of global energy-related C02 emissions, but also because reducing emissions from sources such as the transport sector will involve further electrification - since many of the most promising low-carbon energy technologies are those that produce electricity (wind and solar being two examples).