EIO-LCA Web Forum

Hi, I'm writing a paper on the total embodied energy in a geothermal power plant. I have cost data for the components of the plant and am matching them to approximate EIO-LCA (2002) categories. What I'm finding is that the sum of the embodied energy for each component is far less than the embodied energy value that the EIO-LCA table gives for the generation of electricity, which is 111 TJ/MM$. Is this due to the fact that the EIO-LCA value for electricity generation takes into account the parasitic electricity load? Is it also counting embodied energy of the fuel itself? Thanks for your help.

Kyle Kampa

Kyle:

First, modeling energy systems in IO models is tricky for several reasons. First off, there is only a single power generation sector (as you point out below). That sector encompasses all generation in the US, but inevitably results are for average production of electricity (which at the time was more than 50% coal, 20% NG, 20% nuclear, etc).

Thus, If you run EIO-LCA for $1M of power generation, you get the total energy used across the supply chain to make $1M of electricity using the weighted average mix of generation assets above. Its a relatively high number, and it is dominated by the embodied energy of the coal and natural gas that goes into making fossil-based electricity. The embodied energy needed for making everything else in the supply chain is included as well.

However, investments in capital are generally not included. Small purchases of equipment, yes, but construction of power plants, no. Thus as you're building up your model of geothermal, you're probably including things that are not even included in the regular average sector's model.

Compared to geothermal these are massive differences.