Ferg's Finds
This is a short weekly email that covers a few things I’ve found interesting during the week.
Article(s)
The hidden costs of solar photovoltaic power
This section jumped out at me:
Several previous authors “by joint agreement”[22] excluded the CO2 emissions from all non-fossil carbon sources (charcoal, wood chips), from power generation, and the transportation of raw material.
So remove the emissions from the 2.4 tonnes of wood chips, the coal power generation and transportation, got it.
Podcast/Video
Both of these were damn good:
Louis-Vincent Gave & Harris “Kuppy” Kupperman on De-Dollarization & De-Sinafication
$500 Uranium, Rotation From SPUT into URNM & URNJ, Production Issues | John Ciampaglia Interview
Quote(s)
“Some things are believed because they are true. But many things are believed simply because they have been asserted repeatedly.”
-Thomas Sowell
Tweet
Long term developing market demand growth is the story; fears of demand destruction from recession are a distraction.
Charts
Japan corporates are quietly doing good things.
Something I'm Pondering
I’m pondering the difference in many of the EROI (energy return on investment) calculations. Wikipedia gives you this breakdown.
What caught my eye was the variance in wind turbines EROI (circled below)
What explains the 2.3MW turbine getting an EROI of 51 or over 3x the 1.5MW turbine EROI?
The links provided above were of little use, so I ended up on Vesta's site looking through the life cycle assessment of some of their turbines, with claims of an EROI of 40.
What I found were recycling assumptions and/or capacity factor assumptions massively boost EROI.
The most egregious assumption is the “avoided impacts approach” where it is assumed the majority of the materials can be recycled at the end of life, substantially reducing energy input and boosting EROI. “Can be recycled” is very different from will be recycled i.e. take the tonnes of rebar in the foundations covered in concrete to start. Then, even if you do extract it, all you have is scrap, which needs to be processed, hence more energy.
The other method is the “Recycled content approach” which looks at the percentage of recycled material that is used to make new steel for example and reduces the input energy per unit accordingly in the first calculation of embedded energy. This does reduce energy input but by a much smaller amount than the avoided impacts method.
In the Vestas study "avoided impacts approach" gave an EROI of 40, and the "Recycled content approach" gave an EROI of 28.8, and I'm going to take a wild guess and say without it, EROI would be back in the teens.
The other way to goose EROI is to assume nameplate capacity factors instead of actual figures from operation, i.e. solar, on average, has a capacity factor of 20%; in Germany, it currently has an 11% capacity factor.
Using ChatGPT as a means to gauge "internet consensus" on EROI gives this back-to-front ranking.
Hope you’re all having a great week.
Cheers,
Ferg
P.S. If you’re interested in my story and why I started this Substack, you can read the story here.
I had some ideas on why the EROEIs may be worse for a larger windmill and started to write down the ideas. I then turned to chatGPT which actually summed my ideas better than I could so here is the chatGPT summary 1-4:
1. Size and components: The E-82 wind turbine is larger than the E-66, which means it might require more materials, manufacturing processes, and maintenance efforts. The larger size could result in increased energy consumption during construction, transportation, and installation.
2. Advanced features and technology: The E-82 wind turbine might incorporate more advanced features or technology compared to the E-66, such as a higher hub height, longer rotor blades, or a more sophisticated control system. These additional features could enhance performance but might also require more energy for manufacturing, operation, and maintenance.
3. Environmental conditions: EROEI can also be affected by the wind resource at the site where the wind turbines are deployed. If the E-82 turbines are installed in an area with lower wind speeds or less consistent wind patterns compared to the E-66, they might need to operate at a lower capacity factor, resulting in decreased energy output.
4. Design choices: Enercon might have made specific design choices while developing the E-82 that prioritized other factors such as increased power output or improved reliability, which could have led to a trade-off in terms of its EROEI.
An obvious problem with wikipedia in this case is that there are no good references. The different papers that were referred to were written between 1998 and 2011 (these numbers are negotiable too depending on which papers we want to include in the comparison).
Hi Ferg,
I covered the EROEI calcs for onshore and offshore Wind Power here:
https://davidturver.substack.com/p/eroei-eroi-of-onshore-offshore-wind-power
You're right about the significance of the different methods of treating recycling and load factors. One other big impact is the square-cube law where the output of a turbine increases with the square of the blade size, but the material input increases with the cube of the blade size. So, larger turbines are likely to have lower EROEI. I came up with 17.7 for onshore wind and somewhere between 12 and 14 for offshore.