Case study on decarbonization strategies for LNG export terminals using heat and power from CSP/PV hybrid plants

Abstract

The race towards decarbonization is driving major oil and gas companies to explore means to use renewable heat and power for their plants as part of their commitment to reduce their carbon intensity by 80% to 100% by 2050 (Holbrook, 2023). In terms of GHG (Greenhouse Gas) emissions, natural gas is considered the cleanest fossil fuel option available, and decarbonization of new LNG (Liquefied Natural Gas) projects is on the radar of many LNG projects developers. In addition, LNG cargos will have to be certified in the future by accredited authorities to meet defined GHG emission levels (Stern, 2019).

This research study investigates a new concept of providing both heat and power from a PV (Photovoltaic) and CSP (Concentrated Solar Power) hybrid plant to meet the energy demand of an LNG export terminal. Two locations have been investigated for potential future LNG projects: Karratha in Australia and Ras Laffan in Qatar. Both locations have DNI values higher than 2000 kWh/m²/year, which is the minimum level required for CSP technology (Lovegrove and Stein, 2021).

The LCCA (Levelized Cost of CO2 abatement) was used to compare the various solar configurations to select the option that will bring the greatest amount of CO2 reduction for the same investment cost (CGEP, 2020). The solar configurations technical parameters were defined based on the surface land available, natural gas feed composition and LNG plant design characteristics. The techno-economic assessment was carried-out taking into consideration the electricity price, the grid carbon intensity, and the CO2 tax in the region.

Whilst in Australia a collocated single plant is favourable in terms of land availability and DNI (Direct Normal Irradiation) level, in Qatar, heat and power production have been separated into two distinct locations. Next to the LNG plant, a CSP plant provides heat only, whereas 130 km away, the hybrid PV/CSP plant located at Qurain EL Bawl provides electric power.

The results indicate that the PV/CSP hybrid plant significantly accelerates the decarbonization of energy supply to the “All electric” LNG Plant. Depending on the solar field size, the quantity of CO₂ emitted between 2025 and 2050 is reduced by 78–81% for Karratha (Australia) and by 82–88% for Ras Laffan (Qatar) compared to a grid connected plant.

In addition, the economic assessment indicated that buying electricity from the grid during the period 2025–2050 would be more expensive for Australia then investing in a PV/CSP plant. In Qatar, the LCOE range of 93–110 US$/MWh is not competitive with the price of electricity in the region Qatar, mainly because of energy subsidies, however both the carbon tax and electricity price will need to be raised to the same level as in Australia to diversify and expand the power sector in the region.