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Gaspar do Amaral

Energy and the power system

The Abyss of Rigour: The Illusion of Cheap Energy and the Death of Synchronous Inertia

Having energy is not enough; it has to arrive stable: the illusion of cheap energy when the inertia of the machines disappears

Gaspar do Amaral · 28 March 2026

Translated from the Portuguese original. This version was issued on 27 October 2026.

PDF (11 pages)Discussion on LinkedIn (in Portuguese)

Original illustration of the article, with its texts in Portuguese. Title: “O Abismo do Rigor: A Ilusão da Energia Barata e a Morte da Inércia Síncrona”, Eng.º Gaspar do Amaral. On the left, the “Campo da Retórica Económica” (field of economic rhetoric): a man with a megaphone among charts — “Deflação do preço grossista” (wholesale price deflation), “Competitividade ibérica” (Iberian competitiveness) — and speech bubbles: “Custo marginal zero” (zero marginal cost), “Simplificação conveniente” (convenient simplification), “Certeza do mercado” (market certainty), “As baterias já são mais baratas que o gás. Conetividade contingente!” (batteries are already cheaper than gas. Contingent connectivity!), “Diluição de custos fixos” (dilution of fixed costs). In the middle, “O Abismo do Rigor” (the abyss of rigour), crossed by a broken “Ponte da ‘flexibilidade’” (bridge of “flexibility”) above “Previsões económicas” (economic forecasts) and three warning signs: “Risco de blackout” (blackout risk), “Jitter energético” (energy jitter), “Falha de resiliência” (resilience failure); a chain is marked “Leis da física” (laws of physics). On the right, the “Fortaleza da Engenharia de Sistemas” (fortress of systems engineering): power lines, “Inércia síncrona” (synchronous inertia), engineers at control panels — “Frequência 50,0 Hz” (frequency 50.0 Hz), “Controlo de ROCOF” (ROCOF control), “Qualidade de sinal” (signal quality) — and two signs: “A rede elétrica é uma máquina síncrona, não um mercado de commodities” (the power grid is a synchronous machine, not a commodities market). © Aprecisa.com
Original illustration of the article, with its texts in Portuguese. Title: “O Abismo do Rigor: A Ilusão da Energia Barata e a Morte da Inércia Síncrona”, Eng.º Gaspar do Amaral. On the left, the “Campo da Retórica Económica” (field of economic rhetoric): a man with a megaphone among charts — “Deflação do preço grossista” (wholesale price deflation), “Competitividade ibérica” (Iberian competitiveness) — and speech bubbles: “Custo marginal zero” (zero marginal cost), “Simplificação conveniente” (convenient simplification), “Certeza do mercado” (market certainty), “As baterias já são mais baratas que o gás. Conetividade contingente!” (batteries are already cheaper than gas. Contingent connectivity!), “Diluição de custos fixos” (dilution of fixed costs). In the middle, “O Abismo do Rigor” (the abyss of rigour), crossed by a broken “Ponte da ‘flexibilidade’” (bridge of “flexibility”) above “Previsões económicas” (economic forecasts) and three warning signs: “Risco de blackout” (blackout risk), “Jitter energético” (energy jitter), “Falha de resiliência” (resilience failure); a chain is marked “Leis da física” (laws of physics). On the right, the “Fortaleza da Engenharia de Sistemas” (fortress of systems engineering): power lines, “Inércia síncrona” (synchronous inertia), engineers at control panels — “Frequência 50,0 Hz” (frequency 50.0 Hz), “Controlo de ROCOF” (ROCOF control), “Qualidade de sinal” (signal quality) — and two signs: “A rede elétrica é uma máquina síncrona, não um mercado de commodities” (the power grid is a synchronous machine, not a commodities market). © Aprecisa.com

Introduction: “To drive a car, it is not enough to put fuel in it”

A few elementary analogies:

Nobody acquires a transport asset merely to contemplate a “full tank” at rest. The purchase is aimed at operational performance: guaranteed torque, reliable motion and the integrity of the journey between point A and point B. In the power system, the “fuel” is the electron (raw energy), but “performance” is defined by Quality of Service (QoS) — keeping the voltage stable and controlling the frequency rigorously. As Vaclav Smil shows in Energy and Civilization, the real driver of GDP is not the theoretical price of energy, but its energy density and the resilience of its delivery.

The penetration of renewables with electrochemical storage resembles a highly efficient digital banking system: it speeds up flows, but lacks intrinsic backing (except for synthetic emulation through grid-forming inverters, which still lack the scale and critical mass to replace the kinetic energy of the large rotating masses). Synchronous inertia is, in this context, the “physical gold” in the vault of the Central Bank. As under the gold standard, we may not draw on that reserve every day, but it is its physical existence — the rotating masses in synchronism — that ensures that our unit of account, the 50 Hz, does not suffer a catastrophic devaluation in a millisecond of contingency. Without this backing of stability, the grid loses its verticalidade (verticality, the author’s term for standing firm on solid foundations) and the system collapses under its own volatility.

1. The Blank Cheque in the Iberian Peninsula: The Chronicle of Technical Abdication

The origin of today’s instability lies in a “blank cheque” written to economic rhetoric at the expense of the physics of the grid. This process took shape at critical legislative moments in the Iberian Peninsula.

The legislative context (Portugal)

Decreto-Lei n.º 15/2022 (Portugal) and Real Decreto-ley 20/2022 (Spain) consolidated the mechanism of Contingent Access (flexible connections). It is essential to clarify the engineering of this process: conditional access is not an Iberian eccentricity; it appears explicitly in the Grids Package and in the directives of the European Commission as a tool for optimising the use of the grid:

The legislative context (Spain)

Under the aegis of the Ministry for the Ecological Transition and the Demographic Challenge (MITECO), the face of the Spanish Electricity System (SEE) was changed by laws aimed at the “Iberian exception” and at the massive acceleration of renewable GW. That is, this Iberian Exception, not recommended in the European Union, lowered the marginal price but increased the opportunity cost through the degradation of signal quality, something that the system-services (balancing) markets in Spain have also reflected with rising prices:

Analysis of Iberian convergence

Comparing these documents, one sees a regulatory symmetry within MIBEL (the Iberian Electricity Market). In both countries:

  1. Acceleration vs. inertia: laws were made to inject electrons quickly (volume), but the management of synchronous inertia and of system services (stability) was left dependent on flexibility mechanisms and the secondary market, not on an immediate structural physical requirement.
  2. Conditional connectivity: the figure of “Access and Connection” in Spain mirrors “Contingent Access” in Portugal, where the developer accepts being disconnected at times of grid saturation so that more capacity-reservation titles can be issued.

This legislative structure reinforces the central thesis: the system is being managed with a “full tank” logic (GW targets), while systems engineering struggles to maintain torque and reliability (operational stability) in the face of a physical infrastructure that does not keep up with the speed of the legislated paper in the Iberian Peninsula.

The paradox of grid-forming and synchronous compensators

The full recognition that synchronous inertia is vital is found in the very plans of the Iberian system operators (REN and REE), which provide for the installation of synchronous compensators. [...] The fact that we need to install synchronous compensators and, in future, deploy grid-forming inverters on a massive scale [...] proves the central thesis: inertia has to be restored at very high CAPEX costs, reflected in the Access Tariffs:

Table in the original (in Portuguese). Columns: country/region · rigour strategy (2022–2026) · technical relevance. France — “Base Nuclear Firme” (firm nuclear base): guarantees synchronous inertia and compliance with Regulation (EU) 2019/943. Germany — “Compensadores Síncronos” (synchronous compensators): massive investment in hardware to compensate for the loss of rotating machines. Iberia — “Conetividade Contingente” (contingent connectivity): transfer of the stability risk from the operator to the end user. © Aprecisa.com
Table in the original (in Portuguese). Columns: country/region · rigour strategy (2022–2026) · technical relevance. France — “Base Nuclear Firme” (firm nuclear base): guarantees synchronous inertia and compliance with Regulation (EU) 2019/943. Germany — “Compensadores Síncronos” (synchronous compensators): massive investment in hardware to compensate for the loss of rotating machines. Iberia — “Conetividade Contingente” (contingent connectivity): transfer of the stability risk from the operator to the end user. © Aprecisa.com

2. Voltage Control, the RfG and the Iberian “Risk Premium”

Portuguese excellence: Portugal complies rigorously with the European network codes (Requirements for Generators, RfG), and has a dynamic voltage-control system far superior to Spain’s.

The bill for instability: the ENTSO-E expert panel report confirmed that the central problem of the Iberian blackout was deficient voltage control in Spain.

However, because we operate in a synchronous block (MIBEL), our neighbour’s structural weakness is reflected in our bill.

The fallacy of substitution and the masters’ rebuttal

The economic concept: “Batteries (BESS) replace gas because the marginal cost is lower.”

The rebuttal of rigour:

3. “Contingent Connectivity” vs. European Standards

The idea that industrial consumption should be “flexible” (that is, interruptible without notice) collides with the rules of ENTSO-E (Regulation (EU) 2019/943). High-value industry does not survive on “energy if and when available”. Conventional batteries (grid-following) are static energy-shifting converters. They inject active power, but provide no mechanical inertia, nor do they have the thermal oversizing to inject the massive fault currents (10 kA to 20 kA).

Analysis of the Recitals and Articles of the Regulation shows that there are several evident areas that could be explored in the context of the article, especially with regard to system stability and the transition to renewable energy:

Benoît Chevalier and Steve Keen (The Debunking Economics) argue that productivity is linked to available exergy (useful energy). A system that imposes dispatch restrictions on the consumer is transferring the cost of the grid’s inefficiency to the OPEX of factories.

4. The Paradigm of “Conditional Connectivity” (DL 15/2022)

Separating the concepts: grid flexibility vs. synchronous inertia — a common mistake in macroeconomic analysis is to merge congestion management with dynamic stability. Conditional access manages power flows (it prevents the thermal saturation of cables). Synchronous inertia manages the variation of frequency (the ROCOF). They are orthogonal axes. Solving local congestion with flexibility does not give the system back the global kinetic mass it has lost. In practice, new power stations were authorised to connect on the undertaking that they would be “cut” (curtailment) whenever the grid saturates.

That is, Conditional Access serves to manage cables that are heating up (congestion), not to manage the grid’s lack of inertia.

5. Riding Roughshod over Technical Opinions (DL 30-A/2022)

At the height of the energy crisis (after Ukraine), the simplification of environmental and technical licensing aimed at rapid decarbonisation targets. In engineering, however, “fast” is often the opposite of “robust”.

6. Relevance of the References: The Final Confrontation

Table in the original (in Portuguese). Columns: world reference · concept applied to the Decree-Laws (2022–2026) · engineering diagnosis. Gretchen Bakke — the grid is a machine that demands balance in real time: DL 15/2022 treats the grid like a data warehouse, ignoring that the electron does not wait in a queue. Nicholas Georgescu-Roegen — the Entropy Law in the economic process: the dispersal of generation (simplified by DL 30-A/2022) increases the disorder of the system and the costs of managing it. Thomas Homer-Dixon — the ingenuity gap: politicians believe that technology (batteries) solves everything, ignoring the physics of synchronous inertia. Jean-Marc Jancovici — energy is the “slave” of the modern economy: if the slave is “flexible” (intermittent), industrial production becomes erratic and loses global competitiveness. © Aprecisa.com
Table in the original (in Portuguese). Columns: world reference · concept applied to the Decree-Laws (2022–2026) · engineering diagnosis. Gretchen Bakke — the grid is a machine that demands balance in real time: DL 15/2022 treats the grid like a data warehouse, ignoring that the electron does not wait in a queue. Nicholas Georgescu-Roegen — the Entropy Law in the economic process: the dispersal of generation (simplified by DL 30-A/2022) increases the disorder of the system and the costs of managing it. Thomas Homer-Dixon — the ingenuity gap: politicians believe that technology (batteries) solves everything, ignoring the physics of synchronous inertia. Jean-Marc Jancovici — energy is the “slave” of the modern economy: if the slave is “flexible” (intermittent), industrial production becomes erratic and loses global competitiveness. © Aprecisa.com

7. Data Audit: Wholesale Price vs. System Cost

The “argumentative decoration” (a term coined by João Vermelho Neves) that focuses only on the wholesale market hides the costs of:

  1. System services: the cost of maintaining fast reserve to compensate for renewable jitter.
  2. Grid reinforcement (CAPEX): the investment by REN and REE that will be spread over the tariff, cancelling out the savings in generation.
  3. Security of supply: dependence on interconnections that ENTSO-E and ACER monitor with growing concern, a regulatory “yellow card”.
Original illustration, with its texts in Portuguese (some in English): “O Abismo do Rigor: Estabilidade de Frequência vs. Volatilidade Legislativa” (frequency stability vs. legislative volatility), Eng.º Gaspar do Amaral. On the left, “Cenário A: O Lastro do Rigor (Modelo Síncrono Tradicional)” (scenario A: the backing of rigour, traditional synchronous model): turbogenerators and synchronous machines, “Inércia Síncrona” (synchronous inertia), “Ouro Físico — Banco Central” (physical gold — central bank), the wave “50 Hz Perfeitamente Estável — Linha de Base Sólida” (perfectly stable 50 Hz — solid baseline), “Determinismo Energético” (energy determinism), “Qualidade de Serviço (QoS)” (quality of service) and “Robustez da Rede e Serviços de Sistema” (grid robustness and system services). On the right, “Cenário B: O Abismo da Volatilidade (Modelo Renovável Baseado em Inversores)” (scenario B: the abyss of volatility, inverter-based renewable model): the wave “50 Hz com Jitter — Alto ROCOF, Incerteza Operacional” (50 Hz with jitter — high ROCOF, operational uncertainty), “Sistema Estocástico” (stochastic system), “Dependência de Mercados de Ajuste” (dependence on balancing markets), “Metas de GW Instalados (Depósito Cheio)” (installed-GW targets, full tank), “Conetividade Condicionada” (conditional connectivity), “Conversores Eletrónicos” (electronic converters) and “Banco Digital” (digital bank). In the middle, a car cut in two: “Componentes Mecânicos Desgastados ou Ausentes” (worn or missing mechanical components). © Aprecisa.com
Original illustration, with its texts in Portuguese (some in English): “O Abismo do Rigor: Estabilidade de Frequência vs. Volatilidade Legislativa” (frequency stability vs. legislative volatility), Eng.º Gaspar do Amaral. On the left, “Cenário A: O Lastro do Rigor (Modelo Síncrono Tradicional)” (scenario A: the backing of rigour, traditional synchronous model): turbogenerators and synchronous machines, “Inércia Síncrona” (synchronous inertia), “Ouro Físico — Banco Central” (physical gold — central bank), the wave “50 Hz Perfeitamente Estável — Linha de Base Sólida” (perfectly stable 50 Hz — solid baseline), “Determinismo Energético” (energy determinism), “Qualidade de Serviço (QoS)” (quality of service) and “Robustez da Rede e Serviços de Sistema” (grid robustness and system services). On the right, “Cenário B: O Abismo da Volatilidade (Modelo Renovável Baseado em Inversores)” (scenario B: the abyss of volatility, inverter-based renewable model): the wave “50 Hz com Jitter — Alto ROCOF, Incerteza Operacional” (50 Hz with jitter — high ROCOF, operational uncertainty), “Sistema Estocástico” (stochastic system), “Dependência de Mercados de Ajuste” (dependence on balancing markets), “Metas de GW Instalados (Depósito Cheio)” (installed-GW targets, full tank), “Conetividade Condicionada” (conditional connectivity), “Conversores Eletrónicos” (electronic converters) and “Banco Digital” (digital bank). In the middle, a car cut in two: “Componentes Mecânicos Desgastados ou Ausentes” (worn or missing mechanical components). © Aprecisa.com

8. Conclusions

Resilience engineering is not free

The ENTSO-E Expert Panel Report shows that engineering solves the problems of intermittency, but physics presents the bill. Energy has not become cheaper overall; its real cost has been transferred from the “Generation Bill” to the mega-bill of CAPEX for supporting infrastructure (grid-forming batteries, pumped-storage hydro, synchronous compensators and very-low-latency digital networks). We wrote a blank cheque to “flexibility”, and now physics is presenting the bill for instability.

Physics does not accept adjectives

We can legislate “flexibility” and call energy “cheap”, but the power grid, like any high-precision communications system, demands Verticalidade (verticality) and Rigour. Without massive investment in inertia, redundancy and signal stability, the “blank cheque” written by politics will be cashed by physics, in the form of lost industrial competitiveness and the erosion of technological sovereignty in the Iberian Peninsula.

Eng. Gaspar do Amaral

Annex A — References and their relevance

For further reading, consult the sources on which this analysis rests:

  1. Vaclav Smil: Energy Transitions — on the impossibility of leaping over the laws of thermodynamics.
  2. Dieter Helm: Burn Out — the economics of falling oil prices and the farce of subsidies.
  3. Jean-Marc Jancovici: Manicore — the inseparable relationship between stable energy and GDP.
  4. Robert Ayres: Energy, Complexity and Wealth Maximization — why the quality of energy defines the wealth of nations.
  5. Joseph Tainter: The Collapse of Complex Societies — the rising cost of maintaining hyper-complex networks.
  6. Nicholas Georgescu-Roegen: The Entropy Law and the Economic Process — the father of bioeconomics on the inevitable degradation of systems.
  7. Helmuth Trischler: The Anthropocene — a historical perspective on technology and the limits of the planet.
  8. Steve Keen: The New Economics — a critique of neoclassical theory, which ignores energy.
  9. Thomas Homer-Dixon: The Carbon Shift — the complexity of the transition and the risks of rupture.
  10. Gretchen Bakke: The Grid — the biography of humanity’s largest machine and its present fragility.

Methodological note

What this page is. A translation of the article the author published on LinkedIn on 28 March 2026; the full Portuguese version is on this site. The cover illustration, the two tables and the final illustration are the original images, with their texts in Portuguese, and translated captions. The links to sources are those of the original.

Names of laws and the author’s terms. Portuguese and Spanish laws (Decreto-Lei, Real Decreto-ley) have no official English translation and keep their names, with an explanation in brackets; the European regulation is cited by its official English name, Regulation (EU) 2019/943. “O Abismo do Rigor” (The Abyss of Rigour) and Verticalidade (verticality) are the author’s own concepts; the first is translated in the title and both are kept in Portuguese in the text, with a translation.

Changes of form, not of content. The section headings follow the numbering of the original; the separator lines were left out. Obvious slips in the Portuguese page were corrected only in the translation: a doubled comma and a doubled full stop, two misspelt words (“Istoo”, “decoracão”), “União Europa” and “Península Ibéria” (European Union, Iberian Peninsula), and the formula for carbon dioxide, which appears in the Portuguese page as unrendered code (“$CO_{2}$”) and is written here as CO2. The “@” before the name of João Vermelho Neves (a LinkedIn mention) was left out. The two “[...]” in section 1 are in the original.

The discussion is on LinkedIn (in Portuguese)

Comments on this text are made on LinkedIn, where the article was shared in Portuguese. You are welcome to write in English. Agree, disagree or add data: every well-founded objection receives a reply.

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Gaspar do Amaral · Original in Portuguese of 28 March 2026, published on this site; translation issued on 27 October 2026 · Figures and tables © Aprecisa.com · AI-assisted