Optimal renewable energy integration into the process industry using multi-energy hub approach with economic and environmental considerations: Refinery-wide case study

With growing research interest in renewable energy generation and storage technologies, a need arises for a framework integrating renewable energy within the process industry. In this study, the multi-energy hub approach was used to develop a model to achieve economic gains and carbon emissions reduction. Furthermore, a case study on a refinery was carried out to investigate the applicability of the proposed model. Lowest carbon emissions were realized when utilizing wind coupled with concentrated solar power technologies for electricity and heat generation, respectively. This configuration, for the particular refinery case study, mitigated about 9.8 ktonnes carbon dioxide emissions at an additional annual cost of about $88,000, as compared to the assumed case of utilizing grid energy. Whilst considering energy storage, a further reduction of 1.94 ktonnes of carbon emissions can be attained by employing 9.8 MWh of thermal energy storage, at an added annual cost of $275,000. Moreover, different scenarios were investigated to study the impact of schemes such as carbon cap-and-trade and carbon capture and storage on economic costs and carbon dioxide emissions. Under the carbon cap-and-trade scenario, the lowest annual cost while minimizing annual carbon dioxide emissions was realized when a high carbon credit value of $ 0.00014 gCO₂⁻¹ was utilized. A Pareto front was generated, outlining the optimal cost and carbon emissions when employing different configurations and storage technologies.