| Title | Exergoeconomic analysis of the Hellisheiði geothermal power plant |
|---|---|
| Authors | P. Valdimarsson, K. Jakobsson |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | The Hellisheiði geothermal power plant, operating since 2005, produces 300 MW of electricity and 150 MW of heat for district heating. As a co-generation facility, it must allocate production costs between electricity and heat to set appropriate tariffs. While electricity generation is flexible and can adapt to market demands, heat production must meet fixed seasonal needs without variation. This study analyzes the plant’s summer and winter operations using exergoeconomic optimization, which combines exergy (useful energy) analysis with economic evaluation. A detailed thermodynamic model calculates heat and exergy flows at key points within the plant, while a value analysis model estimates monetary flows based on investment and capital costs. Diagrams such as Sankey, Grassmann, and value flow charts are used to visualize plant performance. Key metrics include the exergoeconomic factor, which relates investment cost to inefficiency costs for each component, and the component cost ratio, which highlights components with the greatest impact on product value. These metrics help identify over- or under-engineered components and assess whether component quality aligns with the overall plant performance. The findings provide insights into improving plant efficiency and cost-effectiveness, and the paper concludes with practical design recommendations for similar geothermal plants. |