I thought I’d add to this topic a little. Users have noticed that where eToolLCD has detailed grid impacts for “Importing” and “Exporting” power, this can also have a large effect on the Net Abiotic Resource Depletion of elements for some grids. The reason for this is:
- To supply electricity Abiotic Resources (Minerals) are depleted along the electricity supply chain, in the extraction energy, the power plant, the transmission and distribution.
- In Particular, the transmission and distribution can have high Abiotic Resource depletion due to the rare minerals used in these assets (in some cases probably similar to PV inverters).
- The “Export” grids assume that the transmission and distribution impacts are not offset by the exported power, where as the import grids do offset this (by reducing load on the grid you are reducing the required transmission and distribution infrastructure, but by feeding in, you’re not necessarily reducing this infrastructure).
Note, that if you ran the same scenario assuming no power was fed in (and batteries were used to store energy on site) the abiotic resource depletion would probably be even higher than the grid connected scenario. The best way of using PV energy on a grid that is not yet renewables saturated is:
- Use the energy on site to power existing loads
- Export the power, so others (hopefully nearby) can use the power
- Store and use or export at another time