LAUSR

The strong growth of intermittent electricity generation from solar PV and wind is leading to a greater need for energy storage at grid scale. In this work a techno-economic model has been constructed to calculate the levelised cost of electricity for two systems that can meet an arbitrary energy demand curve: (1) solar PV and battery storage and (2) solar PV with combustion of bio-crude and bio-gas from biomass. The analysis is performed for conditions prevalent in Queensland, Australia where over a gigawatt of new solar PV capacity is being constructed in 2018. The battery storage assumes lithium-ion batteries and costs derived from the recently constructed Homsdale Power Reserve in South Australia. A variable energy demand curve is assumed in the work. The model shows that the parameters with the most impact on the LCOE for the solar PV and battery system are the solar yield, and total installed costs of the battery and solar PV unit. Assuming, battery costs of 750 AUD/kM/b., solar PV costs of 1.6 AUD/W and a project capacity of 240 MWh/d, the LCOE of the solar PV and battery system was calculated to be 170 AUD/MWh. Using total installed costs forecast for the near future, the LCOE is expected to be in the range 150-185 AUD/W for the variable energy demand curve, and over 200 AUD/MWh if a constant supply of power is required. The parameters with the most impact on the LCOE for the solar PV and bio-crude system are the solar yield and total installed cost of the biomass pyrolysis and bio-crude combustion unit. For a 240 MWh/d project scale with variable energy demand, the LCOE for the solar PV and bio-crude system is estimated to be 116 AUD/MWh. Variations in feedstock cost and project scale showed that the LCOE is in the range of 104-125 AUD/MWh. The main conclusion from this work, is that integration of solar PV and the production and combustion of bio-crude and bio-gas using fast pyrolysis of biomass, leads to competitively priced dispatchable renewable energy that is forecast to be cheaper than using solar PV and batteries for the foreseeable future. It has also been found that the combination of solar PV and bio-crude combustion leads to lower LCOEs than using bioenergy alone, due to the rapidly decreasing costs of large scale solar PV. While the solar PV and bio-crude system analysed in this work will likely be a niche solution, in areas with substantial biomass resources, it offers a credible starting point for the development of larger scale bioenergy value chains, with the longer term goal of converting lignocellulosic biomass materials into renewable transportation fuels and chemicals.