Shrinking Silver State South
As I mentioned in a previous post, First Solar's application to build the Silver State South solar project on public land in the Ivanpah Valley does not add up. Southern California Edison only wants to buy 250 megawatts (MW) of energy from the facility, and provided a large generator interconnection agreement (permission to use transmission lines) for 230MW, yet First Solar asked BLM for permission to build a 350 MW facility. That is at least 100 MW of solar facility that may not even be economically feasible.
The math means a lot because the Silver State South project would be built at one of the narrowest points of the Ivanpah Valley, which serves as an important habitat linkage for the threatened desert tortoise. A bigger solar facility equates to a narrower (or non-existent) habitat linkage. A weak or non-existent habitat linkage means this species may lose genetic diversity and resilience needed to face continuing threats to its recovery, including disease, habitat loss, and climate change.
Although the draft supplemental EIS does not consider a 250 megawatt alternative, I figured I would play with the footprint of the 350MW alternative on Google Earth to see what a notional 250MW layout might look like, and how much desert wildlands could be saved. I calculated the number of acres per megawatt by dividing the total acreage for the BLM's preferred layout -- including the permanent and "temporary" disturbance for the drainage basins -- by 350 MW. That leaves us with roughly 9.26 acres per megawatt, including drainage basins. So a 250 MW alternative could be about 2,317 acres -- possibly a bit more, or a bit less depending on how an altered layout changes the drainage basin requirement. But shaving that acreage off of the eastern edge, which obstructs the habitat linkage, could give us nearly a mile wide corridor. That is double the corridor allowed by the proposed 350MW alternative.
Ivanpah Valley is not the place to maximize destruction and corporate profit. First Solar should go back to the drawing board, and hopefully the BLM will consider a more robust conservation alternative.
The math means a lot because the Silver State South project would be built at one of the narrowest points of the Ivanpah Valley, which serves as an important habitat linkage for the threatened desert tortoise. A bigger solar facility equates to a narrower (or non-existent) habitat linkage. A weak or non-existent habitat linkage means this species may lose genetic diversity and resilience needed to face continuing threats to its recovery, including disease, habitat loss, and climate change.
Although the draft supplemental EIS does not consider a 250 megawatt alternative, I figured I would play with the footprint of the 350MW alternative on Google Earth to see what a notional 250MW layout might look like, and how much desert wildlands could be saved. I calculated the number of acres per megawatt by dividing the total acreage for the BLM's preferred layout -- including the permanent and "temporary" disturbance for the drainage basins -- by 350 MW. That leaves us with roughly 9.26 acres per megawatt, including drainage basins. So a 250 MW alternative could be about 2,317 acres -- possibly a bit more, or a bit less depending on how an altered layout changes the drainage basin requirement. But shaving that acreage off of the eastern edge, which obstructs the habitat linkage, could give us nearly a mile wide corridor. That is double the corridor allowed by the proposed 350MW alternative.
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| (Click on image to expand) A comparison of the proposed 350 megawatt Silver State South solar project (magenta outline), and a notional layout for a 250MW alternative (blue outline). The notional 250 MW facility could provide a much wider habitat linkage for the desert tortoise, and save more rare plants and foraging habitat for desert wildlife. |
This idea never occurred to me. My reading of the draft EIS was about a .4 or so mile wide corridor, this suggestion with the 1 mile corridor is double, and would go a long way toward this particular desert tortoise population maintaining its' genetic diversity in the years ahead.
ReplyDeleteIf First Solar and the BLM had any sense, they would jump on this idea. Or just consider moving the project altogether to a less environmentally sensitive area.