Will another several hundred thousand solar panels in the desert make life easier for ravens? Will those same solar panels store heat, thus making survival harder for desert tortoises? Or does it fail the reasonableness test that solar panels will provide relief from and increase exposure to temperature simultaneously?
I would like to discuss two news articles and then bring the information in them together.
First –
2/19 – KCET / ReWire – Feds Green Light 2 More Solar Projects in Ivanpah Valley – On 2/19 the Interior Department approved 2 more projects near the Nevada-California border. Expectation is the two projects combined will kill or injure or require relocation of 2,115 desert tortoises. Those critters are in the threatened category under federal law. (2,115? Two thousand tortoises? Do I need to add some sarcasm or is merely stating the expected impact sufficient ridicule?)
Interesting unintended consequence of the two projects is that hundreds of thousands of photovoltaic cells will provide lots of shade in the hot desert, thus increasing survival rates for ravens, thus reducing survival rates for desert tortoises. Ravens are apparently quite fond of desert tortoises, and not in a BFF kind of way.
Second –
2/24 – KCET /ReWire – Solar Plant May Make Deserts Too Hot For Tortoises – Run that by me again?
Solar plants might increase the temperature on the ground and thus make it more difficult for desert tortoises to survive.
Huh? One more time, please.
The desert would be too hot for the tortoises who live there? Um, that’s the idea. Let me see if I can explain it to myself so you can get the point.
A biologist speaking at a conference in Ontario, CA explained the huge volume of solar panels would create an ‘urban heat island’ effect. If I get the idea, solar panels are designed to capture heat and they convert about one-fifth of that into electricity. The remaining heat is dissipated immediately around them. I think the idea is that 4/5th of the heat is retained at the surface of the desert instead of being reflected back into the air or pulled away by winds or simple convection. Am I close? Anyone care to enlighten me?
That means that the solar panels will absorb lots of heat and convert some to electricity. They will hold the remainder and radiate it back to the ground, which is where the tortoises hang out.
The calculated temperature change is one degree Fahrenheit plus or minus a quarter degree, according to the article. That is a significant change.
When the biologist strings together all his estimates, assumptions, and forecasts, he is estimating the proposed solar panels discussed in the previous article will make the desert tortoises extinct 50 years earlier than would likely happen otherwise.
You can find a summary of his presentation here, starting at page 31. Most of it is over my head.
Bring the two articles together
So perhaps a few hundred thousand solar panels would provide shade and a respite from the heat for ravens. Or perhaps those panels would instead increase the ground temperature making survival more difficult for tortoises.
At first consideration, it seems to my non-scientific brain that those ideas are contradictory. The panels will increase and decrease temperatures simultaneously? Right. My accountant brain wonders if they are both just wild guesses.
On the other hand, maybe it is possible that both of those scenarios can happen simultaneously. Maybe the panels would provide momentary breaks for ravens. Maybe they would retain heat for many hours more than would happen otherwise.
Perhaps ravens who are in the sun all day would be helped by a slight break from direct sun and perhaps tortoises who are underground most of the time can’t handle even a little bit more heat during the day. Maybe they can’t cope with a lot more heat retained after sundown.
Do you suppose someone ought to have an explanation of that apparent contradiction before starting construction on a project that will be around for a few decades?
Perhaps the scientists who study such things should be able to provide answers to each other before construction starts, even if you and I won’t understand what they say.
Perhaps the biologists should be able to identify what impact hundreds of thousands of panels spread over thousands of acres will have on the health and survivability of ravens and the resulting impact on survivability of prey.
Perhaps they should have a handle of the impact on thousands of tortoises who live where the panels will be installed.
Perhaps there ought to be a rough consensus whether the species would even survive two more solar projects.
Those panels will be around for several decades. Maybe we should know their impact before construction, instead of finding the answer after a decade of operation.
Your thoughts?
Can you think of other questions the scientists ought to address before construction?
What do you think? Did I miss something? Am I on the right track?
Comments welcome.