Possibilities for adjustable power from waste incineration plants

The operating responsible for the Danish electricity grid (Energinet.dk) asks for more competitors in the liberalised market for fulfilling national obligations for contracts of standby regulating power (reserve forpligtelser). The Danish electricity supply is characterised by large amount of wind power and power combined with heat production, meaning that the power production is rather inflexible (locked up with wind conditions and demand for heat). More than half of the municipal solid waste in Denmark is incinerated in waste-to-energy (WTE) plants many of which generate both electricity and district heat. The plants typically operate 80-95% of the time and produce electricity also when there is surplus of electricity. The present project investigates if it is possible to fast reduce electricity production from the WTE plants, thereby making them suitable for making standby contracts for regulating power. Analyses, using advanced simulators (developed by Weel and Sandvig), show that electricity production can be reduced fast, when bypassing the steam turbine, without introducing any disturbances in the incineration of waste. Through test experiments on two plants it has been documented that the typical plant is capable of supplying regulating power (reduction) according to the standard conditions that apply