(Conversation recorded on May 24th, 2023)
Show Summary
On this episode, global systems researcher Iñigo Capellán Pérez joins Nate to discuss net energy analysis, and its use as a tool in analyzing the feasibility of an entire system. While net energy analysis is complex and polarized, some form of it will be necessary to guide society into a resource-constrained future. The energy outlook of a technology changes when scaled up to meet the needs of a larger society. Many models and EROI analyses that fail to take a system-wide view and only look at a single technology use case, only reflect the partial net energy story. When looking at the huge scale-up needed for ‘solutions’ such as Green Growth and Net Zero Transitions, do the hopes for renewable technologies hold up the lifestyles we’ve come to expect over the last century of fossil surplus? Do our policymakers and leaders have the full picture to make competent decisions? How can we best use these tools to make creative responses to guide us through a Great Simplification?
About Iñigo Capellán Pérez
Iñigo is an Industrial Engineer currently doing research with The Group of Energy, Economy and Systems Dynamics (GEEDS) of the University of Valladolid. He holds a Master degree in Electric Energy and Sustainable Development and a PhD in Economics with his dissertation on “Development and Application of Environmental Integrated Assessment Modelling towards Sustainability” at the University of the Basque Country. His research interests focus on the analysis and modeling of the energy-economy-environment systems, the transition to renewable energies in the context of the depletion of fossil fuels and climate mitigation and the technical and social transformations towards sustainability.
Show Notes & Links to Learn More:
00:00 – Iñigo Capellán Pérez works, info, GEEDS, and the paper referenced in this episode: Dynamic Energy Return on Energy Investment (EROI) and material requirements in scenarios of global transition to renewable energies
00:45 – EROI, Nate’s Frankly
03:34 – Integrated Assessment Models
03:45 – IPCC Models
06:46 – Peak Oil
10:10 – Degrowth
12:40 – Beyond Growth
16:22 – Biofuels EROI
17:10 – Societies need about 5-15:1 EROI to sustain themselves
17:45 – Carlos de Castro Carranza – GEEDS
25:40 – Green Growth myth of energy substitutability
31:10 – Investment timeline into fossil fuels vs renewables
35:05 – Biophysical Economics
39:35 – Material, land, etc., limitations of renewables
40:20 – Planetary Boundaries
42:39 – Renewables (wind, solar, and geothermal only) are 5% of primary energy production
42:56 – EROI of the system declined and continues to decline
48:25 – Ukraine/Russia impact on energy
49:25 – Dependence on Russian Fertilizer
53:30 – Energy Cooperatives
59:49 – Collapse Jared Diamond
1:02:18 – TGS Episode on Hydrogen
Teaser photo credit: The 40.5 MW Jännersdorf Solar Park in Prignitz, Germany. By Parabel GmbH – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=32375257
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The founders of the EROEI concept were Professor Charles Hall and David Murphy. They originally concluded that the Energy Return on Energy Invested of renewables was not high enough to run the modern world. But studies into this have a huge range.
“Studies have given figures for the EROI of solar energy as low as 3.9 and as high as 45.45. The lowest estimate, produced by Weissbach et al, was thoroughly discredited by technology entrepreneur Ramez Naam as glaringly low, and he estimates the EROI of solar PV at “above 10, and probably above 15…And rising.” In the most thorough meta-study of the EROI of solar PV, conducted by Bhandari et al, 232 papers estimating solar’s EROI were analysed and the mean estimate was 11.6. Mean EROI varied greatly between types of solar PV, with cadmium telluride coming in at an astounding 34.2. It is also important to note that many of these studies focussed on older installations, which lowered the average. Most modern studies find an EROI for polysilicon solar PV of about 16 and future systems will continue to rise.
In a similar meta-study, systems ecologist Charles A.S. Hall as well as researchers Jessica Lambert and Stephen Balogh looked at the data in studies of other energy sources. Their results are shown in the following table (except for solar – due to their results underestimating its EROI by including decades old studies, Ramez Naam’s estimate of 15 is used).“
https://www.vikramsolar.com/eroi-of-solar-energy/
David Murphy also critiqued some of his earlier work with Charles Hall, and said certain EROEI system boundaries needed streamlining. So he did a meta analysis of the literature and clarified those. With efficiency gains in manufacturing more solar panels from less materials, Dr David Murphy now categorically puts solar at 10 and oil down at 4.6! That’s one of the FOUNDERS of the very concept of EROEI saying solar is now higher than oil.
https://www.sciencedirect.com/science/article/pii/S0301421513003856
NOTE: NO MASSIVE BATTERY BACKUP! Some try to debunk wind and solar EROEI’s by overcounting the storage required. But now it seems most renewable energy papers emphasise OVERBUILDING wind and solar themselves to avoid MASSIVE storage costs. Even better – overbuild solar and wind across a wide geographic area. HVDC lines only lose 3% across 1000 km, so it is possible for Spanish solar to help run Finland, and Finnish wind to then return the favour at night. Now Overbuild renewables with building for winter as your guide. Solar is currently 1/4 the cost of nuclear (Lazard). When the solar and wind grid is Overbuilt, it’s not only saving money on expensive storage but saving the EROEI as well. There’s another way to save EROEI. Don’t build metal batteries for bulk grid storage – push water uphill instead! A big pumped hydro dam takes VASTLY less metal and energy to make than batteries, and lasts for 100 years. Professor Andrew Blakers of the Australian National University says 2 days storage should be provided by off-river pumped hydro systems which are faster and cheaper to build than on-river. (You just slowly pump the water in later. Cover in floating solar panels to reduce evaporation and you’re done!) The world has 100 TIMES more sites than we need. https://re100.eng.anu.edu.au/global/ We might need an hour or two sodium battery capacity to kick in and give the pumped-hydro a chance to work. (Sodium is less toxic, less fire prone, and 30% cheaper than lithium. And SUPER-abundant in sea-salt!) In summary: don’t cheat. Don’t over-emphasise the sunk energy costs in building MASSIVE batteries that most renewable energy papers conclude we do not need in the first place!