Hybrid Life-Cycle Assessments (LCAs) combine input-output analysis with process analysis. By taking this approach, on-site, first- and second-order process data on environmental impacts may be collected for the product or service system under study, while higher-order requirements are covered by input-output analysis.
‘Conventional’ LCAs are based only on process analysis approach, meaning that only on-site, most first-order, and some second-order impacts are considered. However, the truncation of the system boundary leads to a significant underestimation of the true impact (see the boundary problem). Using input-output analysis, the error caused by this truncation can be avoided. A comparative example is given in the table below: Embodied emissions are at least twice as much when comparing the conventional LCA method with the holistic, hybrid input-output analysis approach.
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Our LCA projects have been commissioned by various stakeholders, such as industry, government agencies, NGOs and research institutions. We have carried out LCA projects have been carried for:
- Water service providers;
- Food industry;
- Manufacturing industry;
- Waste management;
- Energy sector and
- Electronic industry.
We offer:
- Life Cycle Assessment studies based on hybrid, process and input-output approach depending on the specific needs of the client
- Life Cycle Costing studies and
- Life Cycle Engineering studies.
For more information – Contact us for copies of articles on life-cycle assessment of energy supply systems:
- Lenzen M and Wachsmann U, Wind energy converters in Brazil and Germany: an example for geographical variability in LCA, Applied Energy, in press, 2003.
- Lenzen M and Munksgaard J, Energy and CO2 life-cycle analyses of wind turbines – review and applications, Renewable Energy 26 (3), 339-362, 2002.
- Dey C and Lenzen M, Greenhouse gas analysis of electricity generation systems, ANZSES Solar 2000 Conference, Griffith University, Brisbane, Australia, 2000.
- Lenzen M, Greenhouse gas analysis of solar-thermal electricity generation, Solar Energy 65 (6), 353-368, 1999.