Hands-On Examples of Process-Based LCAs H. Scott Matthews Civil and Environmental Engineering Carnegie Mellon University

Simplified LCA procedure in practice Draw a process flow diagram Identify required data Based on the data quality requirements set, start to gather data from (1) on-site visit, (2) survey, (3) literatures, (4) model calculation, (5) databases. Data validation Prepare an inventory table

Streamlined LCA Reading on website (for today) Admits there is a “continuum” or spectrum of needs and requirements when doing LCA –Suggest various boundaries appropriate –Choices of inputs/output/etc ok

Some notes from NREL LCI Database User’s Guide Four kinds of LCI data on flows: –Inputs from technosphere (other processes) –Inputs from nature –Outputs to nature –Products / co-product outputs (not to nature) Provides allocated and unallocated data (unallocated better - can allocate yourself)

Using the NREL LCI Database Look at the User’s Guide on website Understand terminology and flows Look at Coal and Electricity Generation data (handout)

Energy Balance for Typical Coal Plant efficiencyinpowerstat/energylosses/energylosses.htm

Question 1: Streamlined Coal LCI Just use information from previous slide, and provided information (from NREL database) on coal production and utility What is total energy (GJ) required to make electricity? Conversions: 1 lb coal ~ BTU –1 BTU =1054 Joule; –Gasoline ~ BTU/gallon –Distillate (e.g., diesel) ~ 135,000 BTU/gallon – Residual ~ 150,000 BTU/gallon –1 ft^3 of natural gas ~ 1000 BTU –Truck transportation ~2500 BTU/ton-mile

Now.. Can we now follow how the NREL inventory for “Electricity Generation” comes from? (given our insights on coal)