<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Omie on lo0 — Tech Blog</title><link>https://blog.lo0.es/en/tags/omie/</link><description>Recent content in Omie on lo0 — Tech Blog</description><generator>Hugo -- gohugo.io</generator><language>en</language><lastBuildDate>Sun, 14 Jun 2026 03:00:00 +0200</lastBuildDate><atom:link href="https://blog.lo0.es/en/tags/omie/index.xml" rel="self" type="application/rss+xml"/><item><title>Energy per token in Spain: methodology, the electricity market and the cases of speculation</title><link>https://blog.lo0.es/en/posts/energy-per-token-spain-methodology-electricity-market-speculation/</link><pubDate>Sun, 14 Jun 2026 03:00:00 +0200</pubDate><guid>https://blog.lo0.es/en/posts/energy-per-token-spain-methodology-electricity-market-speculation/</guid><description>&lt;blockquote>
&lt;p>Notation: amounts in &lt;strong>euros (N €)&lt;/strong>, decimals with a point. The whole article is focused on
the &lt;strong>Spanish electricity market&lt;/strong> (OMIE). The dollar symbol is not used (on this site it is
a formula delimiter).&lt;/p>
&lt;/blockquote>
&lt;h2 id="what-this-article-covers">What this article covers&lt;/h2>
&lt;p>This is the second article of the &lt;strong>energy&lt;/strong> track (C2), and deliberately longer, because it puts
together two things that are almost never told together: the &lt;strong>technical methodology&lt;/strong> of measuring
energy per token, and the &lt;strong>reality of the Spanish electricity market&lt;/strong> that puts a price on that
energy. For an inference platform in Spain, the J/token figure is half the story; the other half is
that those kilowatt-hours are bought in a market that is &lt;strong>marginal-priced, volatile and with
documented cases of manipulation&lt;/strong>. Anyone who sizes the electricity cost of a cluster without
understanding how the price is formed in OMIE, and why it has tripled in a year, is building
30–50 % of the TCO on sand. This article covers the measurement, the market, the cases of
speculation and the strategies for not being left exposed. No partisan opinions: data, market
mechanics and documented facts, with their sources.&lt;/p>
&lt;hr>
&lt;h2 id="the-identity-energy-per-token-and-why-the-price-rules">The identity: energy per token, and why the price rules&lt;/h2>
&lt;p>Energy per token comes from the identity set out in the &lt;a href="https://blog.lo0.es/en/posts/cost-performance-energy-three-axes-llm-inference/">opening article&lt;/a>:&lt;/p>
$$\text{energy per token (J)} = \frac{\text{average power (W)}}{\text{throughput (tok/s)}}$$
&lt;p>And the &lt;strong>electricity cost per token&lt;/strong> is that energy multiplied by the price of electricity:&lt;/p>
$$\text{electricity cost per token} = \text{energy per token (kWh)} \times \text{PUE} \times \text{price (€/kWh)}$$
&lt;p>Here is the point of this article: the first two factors (energy and PUE) are controlled by your
engineering; the third, the &lt;strong>price&lt;/strong>, is set by the Spanish electricity market, and it is the one
that moves most. The same workload, with the same efficiency, can cost three times as much in
electricity depending on the month, not because of the technology but because of OMIE. That is why
measuring energy per token well is necessary but not sufficient: you have to understand the price
variable that multiplies it.&lt;/p>
&lt;hr>
&lt;h2 id="methodology-measuring-energy-per-token-without-fooling-yourself">Methodology: measuring energy per token without fooling yourself&lt;/h2>
&lt;p>Before the market, the measurement. As we saw in &lt;a href="https://blog.lo0.es/en/posts/ai-energy-benchmarking-frameworks-metrics-state-of-the-art/">the energy introduction&lt;/a>,
the energy-per-token figure has four instrumentation decisions that change the
result:&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Decision&lt;/th>
&lt;th>Trap&lt;/th>
&lt;th>Good practice&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>Sampling frequency&lt;/td>
&lt;td>coarse sampling misses the prefill peaks&lt;/td>
&lt;td>sample finely (sub-second)&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Board vs node&lt;/td>
&lt;td>the GPU alone underestimates by 10–20 %&lt;/td>
&lt;td>measure the whole node or declare the limit&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Time window&lt;/td>
&lt;td>including warm-up or shutdown distorts the J/token&lt;/td>
&lt;td>align the window with the measured workload&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Idle baseline&lt;/td>
&lt;td>attributing or subtracting changes the number&lt;/td>
&lt;td>decide and document it&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;div class="diagram" style="max-width:780px;margin:1rem auto;">
&lt;svg viewBox="0 0 780 200" role="img" aria-label="Alignment of the measurement window: the DCGM power and the tool throughput must cover the same interval, with no warm-up or shutdown" xmlns="http://www.w3.org/2000/svg">
&lt;style>.ax{fill:none;stroke:currentColor;stroke-width:1}.bx{fill:none;stroke:currentColor;stroke-width:1.3}.dsh{fill:none;stroke:currentColor;stroke-width:1.2;stroke-dasharray:4 3}.tl{font:600 12px sans-serif;fill:currentColor}.ts{font:11px sans-serif;fill:currentColor}&lt;/style>
&lt;line class="ax" x1="40" y1="150" x2="740" y2="150"/>
&lt;text x="360" y="175" class="ts">time →&lt;/text>
&lt;rect class="dsh" x="60" y="60" width="90" height="90"/>
&lt;text x="62" y="52" class="ts">warm-up (discard)&lt;/text>
&lt;rect class="bx" x="150" y="40" width="420" height="110"/>
&lt;text x="300" y="33" class="tl">measurement window (aligned)&lt;/text>
&lt;text x="165" y="95" class="ts">power (DCGM) ── J integrated here&lt;/text>
&lt;text x="165" y="115" class="ts">throughput (tool) ── tokens counted here&lt;/text>
&lt;rect class="dsh" x="570" y="60" width="90" height="90"/>
&lt;text x="572" y="52" class="ts">shutdown (discard)&lt;/text>
&lt;text x="40" y="195" class="ts">Energy is the integral of power over time; if the power window and the token window do not match, the J/token does not match the throughput.&lt;/text>
&lt;/svg>
&lt;/div>
&lt;p>The golden rule: &lt;strong>the same window for the power and for the tokens&lt;/strong>. If DCGM integrates the
power of one interval and the benchmark tool counts the tokens of another, the J/token means
nothing. With that settled, you already have the energy per token; the rest of the article is about
what multiplies it.&lt;/p>
&lt;hr>
&lt;h2 id="the-spanish-electricity-market-how-the-price-is-formed">The Spanish electricity market: how the price is formed&lt;/h2>
&lt;p>In Spain (and Portugal), the wholesale price of electricity is set by &lt;strong>OMIE&lt;/strong> (Operador del
Mercado Ibérico de Energía), which runs the day-ahead market and &lt;strong>sets the price for each hour&lt;/strong>
(&lt;a href="https://www.omie.es/">OMIE&lt;/a>). The system is &lt;strong>marginal-priced&lt;/strong> (&lt;em>pay-as-clear&lt;/em>): each hour
supply (the plants, ordered from cheapest to most expensive) and demand are matched, and &lt;strong>the price
for everyone is that of the last plant to enter&lt;/strong>, the marginal one. That marginal price &lt;strong>is the
same across all of Spain&lt;/strong> (except the Canaries) and applies to all agents &lt;strong>regardless
of their initial bid&lt;/strong> (&lt;a href="https://www.energiaysociedad.es/omie-cual-es-su-importancia-para-el-sistema-electrico-espanol-y-portugues/">Energía y Sociedad&lt;/a>).&lt;/p>
&lt;div class="diagram" style="max-width:780px;margin:1rem auto;">
&lt;svg viewBox="0 0 780 250" role="img" aria-label="OMIE marginal clearing: supply ordered from cheap to expensive (renewables, nuclear, gas) crosses demand and the price for everyone is that of the last plant to enter" xmlns="http://www.w3.org/2000/svg">
&lt;style>.ax{fill:none;stroke:currentColor;stroke-width:1}.st{fill:none;stroke:currentColor;stroke-width:1.6}.dsh{fill:none;stroke:currentColor;stroke-width:1.2;stroke-dasharray:4 3}.tl{font:600 12px sans-serif;fill:currentColor}.ts{font:11px sans-serif;fill:currentColor}&lt;/style>
&lt;line class="ax" x1="60" y1="40" x2="60" y2="200"/>
&lt;line class="ax" x1="60" y1="200" x2="700" y2="200"/>
&lt;text x="20" y="120" class="ts" transform="rotate(-90 20 120)">€/MWh&lt;/text>
&lt;text x="360" y="228" class="ts">MWh offered (merit order) →&lt;/text>
&lt;path class="st" d="M60,195 L180,193 L180,180 L320,176 L320,150 L440,140 L440,90 L560,60"/>
&lt;text x="95" y="188" class="ts">renewables ~0&lt;/text>
&lt;text x="230" y="170" class="ts">nuclear&lt;/text>
&lt;text x="360" y="132" class="ts">gas (marginal)&lt;/text>
&lt;line class="st" x1="430" y1="40" x2="430" y2="200"/>
&lt;text x="395" y="52" class="ts">demand&lt;/text>
&lt;line class="dsh" x1="60" y1="120" x2="430" y2="120"/>
&lt;text x="62" y="114" class="tl">marginal price: EVERYONE is paid it&lt;/text>
&lt;text x="60" y="245" class="ts">Renewables and nuclear, cheap to produce, are paid the price gas sets: hence the "windfall profits".&lt;/text>
&lt;/svg>
&lt;/div>
&lt;p>The consequence, central to understanding the bill: when &lt;strong>gas&lt;/strong> is the marginal plant (the usual
case in hours without sun or wind), &lt;strong>renewables, nuclear and hydro, dirt cheap
to produce, are paid the price of gas&lt;/strong>. That difference between production cost and price
received is what are called &lt;strong>&amp;ldquo;windfall profits&amp;rdquo;&lt;/strong>, the heart of the
debate about market design. For the buyer of electricity, a datacenter for
example, it means that the price paid &lt;strong>does not reflect the cost of generating&lt;/strong>, but that of the
most expensive technology needed that hour.&lt;/p>
&lt;hr>
&lt;h2 id="the-volatility-the-price-that-triples-in-a-year">The volatility: the price that triples in a year&lt;/h2>
&lt;p>The marginal-priced market, tied to gas in the expensive hours, produces &lt;strong>enormous volatility&lt;/strong>.
The 2026 data illustrates it: the Spanish wholesale price closed &lt;strong>May 2026 with an average of
54 €/MWh, more than triple the 16.92 €/MWh of the same month in 2025&lt;/strong>
(&lt;a href="https://www.merca2.es/2026/05/30/precio-luz-mayo-2026-disparo-2386473/">Merca2&lt;/a>). Tripling
in a year, without your consumption or your efficiency changing.&lt;/p>
&lt;p>And within a single day, the dispersion is brutal because of the effect of renewables: &lt;strong>solar and
wind enter at prices close to zero&lt;/strong>, and in the midday hours of May 2026 prices
reached &lt;strong>negative&lt;/strong> levels in several sessions (&lt;a href="https://www.merca2.es/2026/05/30/precio-luz-mayo-2026-disparo-2386473/">Merca2&lt;/a>).
The structural context: wind and solar went from &lt;strong>26 % of generation in 2019 to more
than 40 % in the first half of 2024&lt;/strong>, and over that period the wholesale price was &lt;strong>more than
40 % lower&lt;/strong> than it would have been with 2019 renewable levels
(&lt;a href="https://www.bde.es/f/webbe/SES/Secciones/Publicaciones/PublicacionesSeriadas/DocumentosOcasionales/23/Fich/do2316.pdf">Banco de España&lt;/a>).&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Reference&lt;/th>
&lt;th>Value&lt;/th>
&lt;th>Source&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>Wholesale May 2026&lt;/td>
&lt;td>&lt;strong>54 €/MWh&lt;/strong>&lt;/td>
&lt;td>Merca2&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Wholesale May 2025&lt;/td>
&lt;td>&lt;strong>16.92 €/MWh&lt;/strong>&lt;/td>
&lt;td>Merca2&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Year-on-year variation&lt;/td>
&lt;td>&lt;strong>+219 %&lt;/strong> (×3.2)&lt;/td>
&lt;td>derived&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Solar hours 2026&lt;/td>
&lt;td>prices close to &lt;strong>0 or negative&lt;/strong>&lt;/td>
&lt;td>Merca2&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Renewables in generation&lt;/td>
&lt;td>26 % (2019) → &amp;gt;40 % (2024)&lt;/td>
&lt;td>Banco de España&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;p>The reading for a cluster: the electricity part of the TCO &lt;strong>is not a fixed number, it is a variable
with a range of 3× year on year and from zero-price hours to peak hours within the day&lt;/strong>. Sizing the
energy cost with an annual average price and forgetting about it is ignoring the biggest risk in the
model.&lt;/p>
&lt;hr>
&lt;h2 id="the-structure-of-the-bill-wholesale-is-not-what-you-pay">The structure of the bill: wholesale is not what you pay&lt;/h2>
&lt;p>It is worth not confusing the &lt;strong>wholesale price&lt;/strong> (the OMIE pool price, the one the headlines talk
about) with what a company actually pays. On top of the wholesale price come:&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Component&lt;/th>
&lt;th>What it is&lt;/th>
&lt;th>Nature&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>Energy (wholesale)&lt;/td>
&lt;td>the OMIE price hour by hour&lt;/td>
&lt;td>variable, volatile&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Access tolls&lt;/td>
&lt;td>use of the transmission and distribution networks&lt;/td>
&lt;td>regulated&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Charges&lt;/td>
&lt;td>system costs (past renewables, etc.)&lt;/td>
&lt;td>regulated&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Taxes&lt;/td>
&lt;td>IEE (special electricity tax) + VAT&lt;/td>
&lt;td>fiscal&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;p>The result: the &lt;strong>industrial retail&lt;/strong> price a datacenter pays is well above the
wholesale price, since tolls, charges and taxes can &lt;strong>double&lt;/strong> the price of pure energy. That is
why this article always distinguishes between the wholesale price (~0.054 €/kWh in May 2026) and
industrial retail (~0.12 €/kWh): for the TCO the second one matters, but the first is the one that
moves and drags the second with it. A large company can access the wholesale market more
directly (via a supplier or a representative), reducing the mark-up, but taking on the
exposure to volatility that comes with it.&lt;/p>
&lt;p>There is also the &lt;strong>PVPC&lt;/strong> (Precio Voluntario al Pequeño Consumidor), the regulated tariff indexed
to the wholesale price for small consumers; a datacenter does not use PVPC, but its existence explains
why the volatility of the pool reaches public opinion and political debate directly, and,
with it, the regulation that ends up affecting everyone.&lt;/p>
&lt;hr>
&lt;h2 id="the-20212022-crisis-the-origin-of-the-problem">The 2021–2022 crisis: the origin of the problem&lt;/h2>
&lt;p>Today&amp;rsquo;s volatility is not new: it originates in the &lt;strong>gas crisis of 2021–2022&lt;/strong>. When
the price of gas shot up (the marginal plant in many hours), the marginal-pricing system
passed that price on to &lt;strong>all&lt;/strong> electricity, including that generated by cheap renewables, nuclear and
hydro. The result was wholesale prices that were several times the historical
levels and massive &lt;strong>&amp;ldquo;windfall profits&amp;rdquo;&lt;/strong> for generators of cheap
technologies that were paid the price of gas. That episode is what motivated both the &lt;strong>Iberian
exception&lt;/strong> (capping gas in price formation) and the European debate about &lt;strong>redesigning the
market&lt;/strong>, and it explains why, years later, the price is still a first-order risk
variable for anyone consuming a lot of megawatt-hours. For a multi-year TCO model,
the lesson is that the Spanish electricity price has shown it can &lt;strong>multiply within
months&lt;/strong> through external factors (gas geopolitics), and that no assumption of a &amp;ldquo;stable&amp;rdquo; price
survives an episode like that unless it is covered by contract.&lt;/p>
&lt;hr>
&lt;h2 id="the-cases-of-speculation-and-manipulation">The cases of speculation and manipulation&lt;/h2>
&lt;p>The volatility of marginal pricing creates incentives to &lt;strong>manipulate&lt;/strong> the price, and in Spain there are
&lt;strong>documented cases with final CNMC fines&lt;/strong>. The largest sanctions on utilities for
manipulating the wholesale market (&lt;a href="https://nadaesgratis.es/jose-luis-ferreira/manipulacion-del-precio-en-el-mercado-electrico-espanol">Nada es Gratis&lt;/a>):&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Company&lt;/th>
&lt;th>CNMC fine&lt;/th>
&lt;th>Concept&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>&lt;strong>Iberdrola&lt;/strong>&lt;/td>
&lt;td>&lt;strong>25 million €&lt;/strong>&lt;/td>
&lt;td>manipulation of the wholesale price via hydro plants&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>&lt;strong>Naturgy&lt;/strong>&lt;/td>
&lt;td>&lt;strong>19.5 million €&lt;/strong>&lt;/td>
&lt;td>manipulation of the wholesale market&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>&lt;strong>Endesa&lt;/strong>&lt;/td>
&lt;td>&lt;strong>5.8 million €&lt;/strong>&lt;/td>
&lt;td>manipulation of the wholesale market&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;p>The &lt;strong>Iberdrola&lt;/strong> case is the most illustrative of how marginal pricing is gamed: between
&lt;strong>30 November and 23 December 2013&lt;/strong>, the company &lt;strong>raised the prices of several
hydro plants&lt;/strong> so that &lt;strong>they would not clear despite the high prices in the
day-ahead market&lt;/strong> (&lt;a href="https://nadaesgratis.es/jose-luis-ferreira/manipulacion-del-precio-en-el-mercado-electrico-espanol">Nada es Gratis&lt;/a>).
The mechanism: &lt;strong>withhold&lt;/strong> cheap water (not bidding it, or bidding it at a prohibitive price) so that
the clearing needs a more expensive plant, &lt;strong>pushing up the marginal price paid to your whole
portfolio&lt;/strong>. In a &lt;em>pay-as-clear&lt;/em> system, withdrawing cheap capacity raises the price of &lt;strong>everything&lt;/strong>
you sell that hour; the incentive to manipulate is embedded in the design.&lt;/p>
&lt;p>OMIE has supervision mechanisms and carries out audits to prevent manipulation
(&lt;a href="https://www.energiaysociedad.es/omie-cual-es-su-importancia-para-el-sistema-electrico-espanol-y-portugues/">Energía y Sociedad&lt;/a>),
and the CNMC sanctions it when it is detected; the fines above are the proof that it happens. For
the buyer, the relevant point is not to assign blame, but to recognise that &lt;strong>the price paid is
formed in a market where manipulation is possible and has happened&lt;/strong>, and that therefore
exposure to that price is a risk to manage, not a figure to accept.&lt;/p>
&lt;hr>
&lt;h2 id="the-other-speculation-hoarding-grid-capacity-and-the-new-2026-law">The other speculation: hoarding grid capacity (and the new 2026 law)&lt;/h2>
&lt;p>There is a second form of speculation, distinct from price manipulation, that affects
&lt;strong>directly&lt;/strong> anyone who wants to build a datacenter: the &lt;strong>hoarding of access and connection
permits&lt;/strong> to the grid. For years, many developers reserved &lt;strong>connection capacity&lt;/strong> at
grid nodes for projects (mostly renewable) that &lt;strong>had no real intention or capacity
to build&lt;/strong>, blocking that capacity for firm projects and speculating on the value of the
permit. Since an inference platform is a &lt;strong>demand facility&lt;/strong> that needs its connection
point, this bottleneck hits it squarely: grid capacity is a scarce and
hoarded resource.&lt;/p>
&lt;p>The regulatory response of 2026 targets exactly that. The Government (Ministry for the Ecological
Transition) finalised a set of rules, within the framework of &lt;strong>Royal Decree-Law 7/2026&lt;/strong>, to &lt;strong>free up
grid capacity and fight speculation&lt;/strong>, ensuring that firm requests can
connect (&lt;a href="https://elperiodicodelaenergia.com/el-gobierno-ultima-una-normativa-para-liberar-la-capacidad-de-las-redes-electricas-y-combatir-la-especulacion/">El Periódico de la Energía&lt;/a>,
&lt;a href="https://www.fieldfisher.com/es-es/locations/espana/actualidad/nuevo-paquete-regulatorio-energias-renovables">Fieldfisher&lt;/a>).
The central mechanism, with &lt;strong>effect from 22 March 2026&lt;/strong>:&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Element&lt;/th>
&lt;th>Detail&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>Who pays&lt;/td>
&lt;td>holders of access and connection permits for &lt;strong>demand facilities&lt;/strong>&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>What they pay&lt;/td>
&lt;td>a &lt;strong>monthly charge&lt;/strong> for &amp;ldquo;reserving&amp;rdquo; capacity until entering operation&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>How it is calculated&lt;/td>
&lt;td>transmission and distribution tolls &lt;strong>× a &amp;ldquo;k factor&amp;rdquo;&lt;/strong>&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Modulation&lt;/td>
&lt;td>by voltage level and by the &lt;strong>delay&lt;/strong> in commissioning&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>k factor&lt;/td>
&lt;td>to be set by resolution of the Secretary of State for Energy&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;p>The logic: if reserving capacity &lt;strong>costs every month&lt;/strong> and the cost &lt;strong>grows with the delay&lt;/strong>,
hoarding stops being free and the speculator releases the capacity it is not going to use. For a
&lt;strong>real&lt;/strong> datacenter project the implication is twofold: (1) that charge on the reserved capacity has
to be budgeted &lt;strong>during construction&lt;/strong>, and (2) there is a strong incentive to &lt;strong>build
quickly&lt;/strong>, since every month of delay in starting up adds to the charge. In other words, the new law turns
commissioning time into an explicit cost. For the TCO model and the timetable of the
proposal, this is a figure to build in from the start: grid capacity is no longer reserved
&amp;ldquo;just in case&amp;rdquo; for free, and the construction schedule now has a bill attached.&lt;/p>
&lt;hr>
&lt;h2 id="the-design-debate-why-marginal-pricing-rewards-speculation">The design debate: why marginal pricing rewards speculation&lt;/h2>
&lt;p>The underlying problem is not just that some companies manipulate: it is that &lt;strong>the market design
rewards doing it&lt;/strong>. In a &lt;em>pay-as-clear&lt;/em> system (everyone is paid the marginal price), a generator with
a lot of cheap capacity has a perverse incentive: &lt;strong>withdrawing part of its cheap capacity&lt;/strong> raises
the marginal price it is paid &lt;strong>for all the capacity it does sell&lt;/strong>. If you control enough market share, the
extra revenue from raising the price of your whole portfolio can exceed what you lose by not selling
the withdrawn capacity. That is exactly what the CNMC sanctioned in the hydro case.&lt;/p>
&lt;p>The design alternatives under debate:&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Design&lt;/th>
&lt;th>How it pays&lt;/th>
&lt;th>Effect on the incentive to speculate&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>&lt;strong>Pay-as-clear&lt;/strong> (current)&lt;/td>
&lt;td>everyone is paid the marginal price&lt;/td>
&lt;td>high: withdrawing capacity raises the price of everything&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>&lt;strong>Pay-as-bid&lt;/strong>&lt;/td>
&lt;td>each one is paid its own bid&lt;/td>
&lt;td>lower incentive, but strategic bidding&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>&lt;strong>Long-term contracts / PPA&lt;/strong>&lt;/td>
&lt;td>fixed bilateral price&lt;/td>
&lt;td>takes volume out of the pool, reduces exposure&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;p>There is no technical consensus that &lt;em>pay-as-bid&lt;/em> is better (it introduces its own problems of
strategic bidding), and the reform of the European electricity market has opted more for &lt;strong>promoting
long-term contracts (PPA and CfD)&lt;/strong> than for changing the pool mechanism. For the
buyer, the practical conclusion is the same as for the regulator: &lt;strong>taking your volume out of the pool
through forward contracts&lt;/strong> is the most direct way of not being exposed to the marginal price, and to
whoever manipulates it.&lt;/p>
&lt;hr>
&lt;h2 id="the-iberian-exception-a-patch-with-an-expiry-date">The Iberian exception: a patch with an expiry date&lt;/h2>
&lt;p>Faced with the gas price crisis of 2021–2022, the European Commission granted Spain and Portugal
an &lt;strong>exception&lt;/strong> allowing them to &lt;strong>cap the price of the gas used to produce electricity&lt;/strong>
(&lt;a href="https://www.merca2.es/2026/05/30/precio-luz-mayo-2026-disparo-2386473/">market context&lt;/a>).
The &amp;ldquo;Iberian exception&amp;rdquo; partially decoupled the electricity price from gas, containing the peaks.
It is relevant for a multi-year cost projection because it is a &lt;strong>regulatory mechanism with
limited duration&lt;/strong>: any 36-month TCO model has to consider what happens to the price if the
exception changes or expires. Regulation is another price variable, not just the market.&lt;/p>
&lt;hr>
&lt;h2 id="what-it-means-for-the-electricity-cost-of-a-cluster">What it means for the electricity cost of a cluster&lt;/h2>
&lt;p>Putting together energy per token (technical) with the Spanish price (market), the electricity cost per
token of an example node (8×H100, 0.78 kWh per million tokens with PUE) &lt;strong>according to the price
scenario&lt;/strong>:&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Price scenario (Spain)&lt;/th>
&lt;th>€/kWh&lt;/th>
&lt;th>Electricity cost / 1M tokens&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>Solar hour / negative price&lt;/td>
&lt;td>~0&lt;/td>
&lt;td>~0&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>May 2025 (low wholesale)&lt;/td>
&lt;td>0.017&lt;/td>
&lt;td>~0.013 €&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>May 2026 (average wholesale)&lt;/td>
&lt;td>0.054&lt;/td>
&lt;td>~0.042 €&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Industrial retail (with tolls and taxes)&lt;/td>
&lt;td>~0.12&lt;/td>
&lt;td>~0.094 €&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Peak hour / crisis&lt;/td>
&lt;td>0.20+&lt;/td>
&lt;td>~0.16 €&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;p>The range is more than &lt;strong>10×&lt;/strong> between the solar hour and the peak hour, and &lt;strong>3×&lt;/strong> year on year at the
level of the average. Over a fleet consuming megawatt-hours a year, that variability is the difference
between a comfortable TCO and a suffocated one, and it does not depend on your technology but on
&lt;strong>when and how you buy the energy&lt;/strong>.&lt;/p>
&lt;hr>
&lt;h2 id="strategies-for-not-being-left-exposed">Strategies for not being left exposed&lt;/h2>
&lt;p>This is where the technical figure turns into a decision. Four levers for managing
exposure to the Spanish price, from the least to the most structural:&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Strategy&lt;/th>
&lt;th>What it does&lt;/th>
&lt;th>Trade-off&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>&lt;strong>Indexed tariff&lt;/strong>&lt;/td>
&lt;td>you pay the wholesale price hour by hour&lt;/td>
&lt;td>cheap on average, maximum exposure to volatility&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>&lt;strong>Fixed / forward tariff (OMIP)&lt;/strong>&lt;/td>
&lt;td>price locked by contract&lt;/td>
&lt;td>predictability, you pay a premium for the insurance&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>&lt;strong>PPA with a renewable plant&lt;/strong>&lt;/td>
&lt;td>you buy directly from a solar/wind farm&lt;/td>
&lt;td>stable price and low carbon, requires volume and term&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>&lt;strong>Solar self-consumption&lt;/strong>&lt;/td>
&lt;td>you generate on site&lt;/td>
&lt;td>you cover the sunlight hours almost free, capex and space&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>&lt;strong>Temporal scheduling&lt;/strong>&lt;/td>
&lt;td>move shiftable load to cheap hours&lt;/td>
&lt;td>only applies to the non-urgent (batch, fine-tuning)&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;div class="diagram" style="max-width:780px;margin:1rem auto;">
&lt;svg viewBox="0 0 780 210" role="img" aria-label="Energy purchasing strategies against volatility: indexed exposes, fixed/PPA stabilise, self-consumption and scheduling exploit the cheap hours" xmlns="http://www.w3.org/2000/svg">
&lt;style>.bx{fill:none;stroke:currentColor;stroke-width:1.3}.tl{font:600 12px sans-serif;fill:currentColor}.ts{font:11px sans-serif;fill:currentColor}&lt;/style>
&lt;rect class="bx" x="20" y="50" width="170" height="56" rx="6"/>&lt;text x="32" y="72" class="tl">Indexed&lt;/text>&lt;text x="32" y="90" class="ts">maximum exposure&lt;/text>
&lt;rect class="bx" x="210" y="50" width="170" height="56" rx="6"/>&lt;text x="222" y="72" class="tl">Fixed / PPA&lt;/text>&lt;text x="222" y="90" class="ts">predictability (premium)&lt;/text>
&lt;rect class="bx" x="400" y="50" width="170" height="56" rx="6"/>&lt;text x="412" y="72" class="tl">Self-consumption&lt;/text>&lt;text x="412" y="90" class="ts">sunlight hours ~free&lt;/text>
&lt;rect class="bx" x="590" y="50" width="170" height="56" rx="6"/>&lt;text x="602" y="72" class="tl">Scheduling&lt;/text>&lt;text x="602" y="90" class="ts">batch at cheap hours&lt;/text>
&lt;text x="20" y="140" class="ts">← more market exposure · more control / predictability →&lt;/text>
&lt;text x="20" y="180" class="ts">For online inference (non-shiftable): fixed tariff/PPA + self-consumption. For batch/fine-tuning: schedule to off-peak or solar hours.&lt;/text>
&lt;/svg>
&lt;/div>
&lt;p>The sensible combination for an inference platform in Spain: &lt;strong>a PPA or a fixed tariff&lt;/strong> for the
base load (online inference, which cannot be moved), &lt;strong>solar self-consumption&lt;/strong> to cover the midday
hours almost free, and &lt;strong>scheduling&lt;/strong> of the shiftable work (training, overnight batch) towards the
off-peak or peak-solar hours. That turns the volatility of marginal pricing from &lt;strong>risk&lt;/strong> into
&lt;strong>opportunity&lt;/strong>: the same zero-price hours that sink generators&amp;rsquo; revenue are the
cheap hours for whoever consumes.&lt;/p>
&lt;hr>
&lt;h2 id="solar-self-consumption-the-numbers-for-a-cluster">Solar self-consumption: the numbers for a cluster&lt;/h2>
&lt;p>Spain is one of the best places in Europe for solar, and for a datacenter self-consumption
has a clear cost logic. The numbers, for illustration:&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Parameter&lt;/th>
&lt;th>Reference value&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>Solar output in Spain&lt;/td>
&lt;td>~1,400–1,600 kWh per kWp per year&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Capex of an industrial installation&lt;/td>
&lt;td>~600–900 € per kWp&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Panel service life&lt;/td>
&lt;td>~25–30 years&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Electricity cost avoided (retail)&lt;/td>
&lt;td>~0.12 €/kWh&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;p>For a &lt;strong>100 kWp&lt;/strong> installation (warehouse roof): it generates ~150 MWh/year, with a capex of
~70,000–90,000 €. At 0.12 €/kWh avoided, it saves ~18,000 €/year, with a &lt;strong>payback of ~4–6 years&lt;/strong> and
then ~20 years of almost free energy. The snag: a cluster consumes 24/7 and solar only produces by
day, so self-consumption &lt;strong>covers a fraction&lt;/strong>, the midday hours, not everything. But those midday
hours are precisely the ones with &lt;strong>low or negative wholesale prices&lt;/strong>, so self-consumption and the
market complement each other: at night you buy cheap (off-peak), by day you generate. The &lt;em>avoided cost&lt;/em> is
not only that of the energy, it is that of &lt;strong>not being exposed&lt;/strong> to the non-existent solar peak and to
daytime volatility. For a cluster with roof space available, self-consumption is the most solid
structural lever on electricity cost in Spain.&lt;/p>
&lt;hr>
&lt;h2 id="annual-electricity-tco-three-scenarios-for-a-cluster-in-spain">Annual electricity TCO: three scenarios for a cluster in Spain&lt;/h2>
&lt;p>Putting it all together, the annual electricity cost of an 8×H100 node (~7.84 kW with PUE, ~68,700 kWh/year at
100 % utilisation) according to the purchasing strategy, in Spain:&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Strategy&lt;/th>
&lt;th>Effective €/kWh&lt;/th>
&lt;th>Annual electricity cost&lt;/th>
&lt;th>Exposure&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>Indexed (unhedged)&lt;/td>
&lt;td>~0.08 (variable)&lt;/td>
&lt;td>&lt;strong>~5,500 €&lt;/strong> ±a lot&lt;/td>
&lt;td>maximum to volatility&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Fixed / renewable PPA&lt;/td>
&lt;td>~0.06 (stable)&lt;/td>
&lt;td>&lt;strong>~4,120 €&lt;/strong>&lt;/td>
&lt;td>low, predictable&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>PPA + solar self-consumption&lt;/td>
&lt;td>~0.045 (mixed)&lt;/td>
&lt;td>&lt;strong>~3,090 €&lt;/strong>&lt;/td>
&lt;td>low + minimal carbon&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;p>The difference between the worst and the best strategy is &lt;strong>~2,400 €/year per node&lt;/strong>, before counting
the risk: the indexed option can shoot up in a bad month, while PPA+solar is stable and low.
Over a fleet of dozens of nodes and a 36-month horizon, the choice of &lt;strong>how the energy is bought&lt;/strong>
moves the TCO as much as a hardware decision, and it is a lever decided with
contracts, not with engineering. This number feeds directly into the TCO model of the FinOps track
(A8) and the sizing of the proposal.&lt;/p>
&lt;hr>
&lt;h2 id="ppas-the-central-lever-and-its-small-print-in-2026">PPAs: the central lever (and its small print in 2026)&lt;/h2>
&lt;p>Of all the strategies, the &lt;strong>PPA&lt;/strong> (Power Purchase Agreement, a long-term energy purchase
contract) is the most important piece for a datacenter in Spain today, and it deserves a
section of its own because its current situation is &lt;strong>exceptionally favourable… with a catch&lt;/strong>.&lt;/p>
&lt;h3 id="what-a-ppa-is-in-short">What a PPA is, in short&lt;/h3>
&lt;p>A PPA is a &lt;strong>bilateral, long-term contract&lt;/strong> (typically &lt;strong>10–12 years&lt;/strong> in Spain) between
a consumer and a renewable generator, at a &lt;strong>locked price&lt;/strong> per MWh. It takes your volume out of the
OMIE pool: instead of paying the marginal price hour by hour (with its volatility and its exposure to
manipulation), you pay the contract price. There are two families: &lt;strong>physical&lt;/strong> (you receive the energy from
that farm) and &lt;strong>financial/virtual&lt;/strong> (a &lt;em>swap&lt;/em> covering the difference against the market); and two
profile forms: &lt;strong>pay-as-produced&lt;/strong> (you pay for what the farm generates, when it generates, cheap but
intermittent) and &lt;strong>baseload&lt;/strong> (a guaranteed flat profile, more expensive but firm).&lt;/p>
&lt;h3 id="prices-today-historic-lows">Prices today: historic lows&lt;/h3>
&lt;p>Spain is living a unique moment in PPA prices. &lt;strong>Solar PPAs fell to a historic low
of 32.5 €/MWh in the fourth quarter of 2025&lt;/strong>, with the most competitive percentiles &lt;strong>below
30 €/MWh&lt;/strong>, half the French level (&lt;a href="https://www.pv-magazine.es/2026/02/04/la-canibalizacion-provoca-una-caida-record-de-los-precios-de-los-ppas-fotovoltaicos-en-espana-hasta-los-325-e-mwh/">pv-magazine&lt;/a>,
&lt;a href="https://elperiodicodelaenergia.com/la-canibalizacion-acerca-el-precio-de-los-ppas-solares-a-30-mwh-en-espana-la-mitad-que-en-francia/">El Periódico de la Energía&lt;/a>).
Wind sits at around &lt;strong>50–60 €/MWh&lt;/strong>. To put it in context: a solar PPA at 30 €/MWh is
&lt;strong>~0.030 €/kWh&lt;/strong>, less than half the industrial retail price (~0.12 €/kWh) and well below the
volatile wholesale price.&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Technology (PPA, Spain 2026)&lt;/th>
&lt;th>Price&lt;/th>
&lt;th>Reference&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>Solar photovoltaic&lt;/td>
&lt;td>&lt;strong>~32.5 €/MWh&lt;/strong> (percentiles &amp;lt;30)&lt;/td>
&lt;td>pv-magazine&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Wind&lt;/td>
&lt;td>&lt;strong>~50–60 €/MWh&lt;/strong>&lt;/td>
&lt;td>market&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>Industrial retail (for comparison)&lt;/td>
&lt;td>~120 €/MWh&lt;/td>
&lt;td>—&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;h3 id="why-so-cheap-cannibalisation">Why so cheap: cannibalisation&lt;/h3>
&lt;p>The fall is no accident: it is the &lt;strong>cannibalisation&lt;/strong> of photovoltaics. The more solar is installed,
the more midday hours there are with wholesale prices close to zero or negative, which &lt;strong>sinks the value
captured&lt;/strong> by solar (captured prices have fallen below 15 €/MWh), and with it the
price at which farms sign PPAs (&lt;a href="https://www.energiaestrategica.com/espana-atraviesa-un-cierre-de-la-ventana-de-ppas-solares-mientras-el-nuevo-real-decreto-busca-aliviar-la-industria/">Energía Estratégica&lt;/a>).
With &lt;strong>more than 40 GW competing for 30 GW of demand&lt;/strong>, there is an excess of solar supply that cheapens the
PPA. For the industrial consumer it is a historic opportunity; for the solar developer, a crisis
of profitability, hence the talk of the &amp;ldquo;closing of the solar PPA window&amp;rdquo; and of the new
Royal Decree seeking to &lt;strong>restore industrial competitiveness&lt;/strong>.&lt;/p>
&lt;h3 id="spain-european-leader-in-ppas">Spain, European leader in PPAs&lt;/h3>
&lt;p>This is no marginal phenomenon: in &lt;strong>2024 Spain was the country with the most PPAs signed in Europe for the sixth
consecutive year, with 47 agreements for 4.66 GW&lt;/strong> of renewable capacity (&lt;a href="https://www.energiaysociedad.es/energias-renovables/ppaa/">market sources&lt;/a>).
The market is deep, liquid and mature, which makes it easier for a datacenter to find a counterparty.&lt;/p>
&lt;h3 id="the-catch-for-a-datacenter-annual-energy--firm-power">The catch for a datacenter: annual energy ≠ firm power&lt;/h3>
&lt;p>Here is the small print that decides the architecture. A cheap solar PPA &lt;strong>offsets energy over
the year&lt;/strong>, but &lt;strong>does not guarantee physical power every hour&lt;/strong>. And an AI datacenter &lt;strong>cannot
stop&lt;/strong> because there is no wind one January night or because the solar curve falls at dusk
(&lt;a href="https://elperiodicodelaenergia.com/la-gran-decision-energetica-de-los-data-centers">El Periódico de la Energía&lt;/a>).
This is the difference between &lt;strong>energy&lt;/strong> (kWh per year, which the solar PPA covers dirt cheap) and &lt;strong>firm
power&lt;/strong> (kW available for all 8,760 hours, which the sun does not provide). The sector sums it up like this: Spain is now
forced to talk about &lt;strong>firm energy&lt;/strong> (&lt;a href="https://revistacloud.com/los-centros-de-datos-obligan-a-espana-a-hablar-de-energia-firme">Revista Cloud&lt;/a>).&lt;/p>
&lt;p>The consequence for the design of the proposal: a solar PPA at 30 €/MWh is the &lt;strong>ideal cost floor
for the sunlight hours&lt;/strong>, but it has to be &lt;strong>combined&lt;/strong> to cover the rest: a &lt;strong>hybrid PPA&lt;/strong>
(solar + wind, which complement each other over time), &lt;strong>baseload&lt;/strong> for the flat part, or &lt;strong>storage&lt;/strong>
(batteries, which RDL 7/2026 also promotes) to move energy from the sunlight hours to the night. The
sensible energy architecture of a Spanish datacenter in 2026 is not &amp;ldquo;a solar PPA&amp;rdquo;, it is &lt;strong>a cheap
solar PPA as the daytime base + firmness for the hours without sun&lt;/strong> (wind, baseload, batteries or the grid
as backup). Anyone who signs only the cheap solar PPA and discovers in production that they have no firm
power in the small hours will have optimised the cost of the energy and ignored that of &lt;strong>availability&lt;/strong>,
which for an inference platform with an SLO is non-negotiable.&lt;/p>
&lt;h3 id="the-context-the-datacenter-boom-in-spain">The context: the datacenter boom in Spain&lt;/h3>
&lt;p>All of this is happening in the middle of a &lt;strong>boom&lt;/strong>: Spain is positioning itself as the epicentre of southern Europe in
datacenters, with investments of billions and installed capacity doubling towards 2026
(&lt;a href="https://www.datacenterdynamics.com/es/features/data-centers-en-espa%C3%B1a-hacia-2026-un-boom-de-90000-millones-en-proyectos/">DCD&lt;/a>).
The appeal combines cheap renewable PPAs, industrial land more accessible than in other European
digital capitals, and EU jurisdiction. The constraint that tempers it is exactly the one in C2: &lt;strong>the cost of
energy is low but firm power and grid capacity are the bottlenecks&lt;/strong>, and
both are managed with the combination of a hybrid PPA, storage and a connection schedule that
does not fall foul of the hoarding charge.&lt;/p>
&lt;hr>
&lt;h2 id="the-sovereign-and-carbon-angle">The sovereign and carbon angle&lt;/h2>
&lt;p>For a sovereign proposal, Spain has a double advantage worth quantifying. First,
&lt;strong>carbon&lt;/strong>: the Spanish grid runs at around &lt;strong>~150–170 gCO₂/kWh&lt;/strong> (a mix of renewables and gas), well
below Germany (~363) though above nuclear France (~20–60). Second,
&lt;strong>growing renewables&lt;/strong> (&amp;gt;40 % of generation), which pull the price and the carbon
down in the sunlight hours. The argument for the proposal: a cluster in Spain, with solar
self-consumption and a renewable PPA, can achieve at the same time a &lt;strong>low and predictable electricity
cost&lt;/strong> and a &lt;strong>competitive carbon per token&lt;/strong>, within EU jurisdiction. The volatility of marginal pricing is
not only a risk: managed well with contracting and scheduling, it is a cost lever that a
hyperscaler in another region does not exploit in the same way.&lt;/p>
&lt;p>Carbon, moreover, is &lt;strong>variable by the hour&lt;/strong>: in peak-solar hours the intensity of the Spanish
grid drops, so &lt;strong>moving shiftable load to those hours reduces both the cost and the
carbon per token at once&lt;/strong>. The same scheduling strategy serves both axes.&lt;/p>
&lt;hr>
&lt;h2 id="guarantees-of-origin-carbon-has-its-market-too">Guarantees of Origin: carbon has its market too&lt;/h2>
&lt;p>One nuance that connects price speculation with carbon reporting: in Spain (and the EU) there
is a market in &lt;strong>Guarantees of Origin (GoO)&lt;/strong>, certificates attesting that a quantity of
energy was produced from a renewable source. A company can &lt;strong>buy GoOs&lt;/strong> to declare that its
consumption is &amp;ldquo;green&amp;rdquo; in its &lt;strong>market-based&lt;/strong> carbon reporting, even though physically
the electricity it received from the grid had the average intensity of the mix. This creates two ways of
accounting for carbon, with different implications:&lt;/p>
&lt;table>
&lt;thead>
&lt;tr>
&lt;th>Method&lt;/th>
&lt;th>What it counts&lt;/th>
&lt;th>How the figure is brought down&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>
&lt;td>&lt;strong>By location&lt;/strong> (&lt;em>location-based&lt;/em>)&lt;/td>
&lt;td>the real intensity of the Spanish grid that hour&lt;/td>
&lt;td>generate/consume in clean hours; location&lt;/td>
&lt;/tr>
&lt;tr>
&lt;td>&lt;strong>By market&lt;/strong> (&lt;em>market-based&lt;/em>)&lt;/td>
&lt;td>according to the GoOs/PPAs contracted&lt;/td>
&lt;td>buy certificates or sign a PPA&lt;/td>
&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;p>&lt;strong>Location-based&lt;/strong> accounting rewards consuming when the Spanish grid is clean (solar
hours); &lt;strong>market-based&lt;/strong> allows the green attribute to be &amp;ldquo;bought&amp;rdquo; with GoOs. CSRD reporting normally
requires both. The word of caution: the GoO market is relatively cheap, and buying GoOs without
a real PPA behind them is a way of &lt;strong>dressing up&lt;/strong> the figure without changing the physical electricity
you consume, the cost equivalent of accounting &lt;em>greenwashing&lt;/em>. For an honest sovereign
proposal, the robust route is a &lt;strong>real PPA with a Spanish renewable farm&lt;/strong> (which does change the physical
origin and stabilises the price) plus &lt;strong>location-based&lt;/strong> measurement that rewards scheduling to clean
hours, rather than accumulating certificates.&lt;/p>
&lt;hr>
&lt;h2 id="hourly-intensity-the-red-eléctrica-figure">Hourly intensity: the Red Eléctrica figure&lt;/h2>
&lt;p>Spain publishes the &lt;strong>carbon intensity of the grid hour by hour&lt;/strong> (via Red Eléctrica / esios and
ElectricityMaps), and it varies enormously over the day: on a sunny spring afternoon it can
drop to ~80–100 gCO₂/kWh, and on a cold, windless night, with gas cycles, exceed ~250. That
hourly figure is what makes &lt;strong>carbon-aware scheduling&lt;/strong> possible: moving training,
document ingestion or overnight batch to the hours of lowest intensity reduces the carbon per token
of the shiftable work at no technical cost. It is the same lever as price-based scheduling, since the
cheap hours and the clean ones largely coincide in Spain, because both are set by the excess of
solar and wind. Measuring carbon per token &amp;ldquo;on an annual average&amp;rdquo; wastes this information; measuring it
&lt;strong>hour by hour&lt;/strong> and scheduling accordingly is what turns the figure into a real reduction.&lt;/p>
&lt;hr>
&lt;h2 id="energy-per-token-with-the-spanish-price-step-by-step">Energy per token, with the Spanish price, step by step&lt;/h2>
&lt;p>Closing the circle with a complete calculation for the example node, in Spain:&lt;/p>
&lt;ol>
&lt;li>&lt;strong>Energy per token&lt;/strong>: 5,600 W (8×H100) ÷ 2,800 tok/s = &lt;strong>2 J/token&lt;/strong> (board); ×PUE 1.4 =
2.8 J/token effective.&lt;/li>
&lt;li>&lt;strong>Energy per 1M tokens&lt;/strong>: 0.78 kWh (with PUE).&lt;/li>
&lt;li>&lt;strong>Electricity cost per 1M tokens&lt;/strong> by contracting model:
&lt;ul>
&lt;li>Indexed in a solar hour (~0 €/kWh): &lt;strong>~0 €&lt;/strong>.&lt;/li>
&lt;li>Renewable PPA (~0.05 €/kWh stable): &lt;strong>~0.039 €&lt;/strong>.&lt;/li>
&lt;li>Industrial retail (~0.12 €/kWh): &lt;strong>~0.094 €&lt;/strong>.&lt;/li>
&lt;/ul>
&lt;/li>
&lt;li>&lt;strong>Carbon per 1M tokens&lt;/strong>: 0.78 kWh × ~160 gCO₂/kWh = &lt;strong>~125 gCO₂&lt;/strong> (and less in solar
hours).&lt;/li>
&lt;/ol>
&lt;p>The message: the J/token is fixed (your engineering sets it); the &lt;strong>electricity cost per token varies more
than 10× depending on how and when you buy the energy&lt;/strong> in Spain. That is why this article devotes more
space to the market than to the measurement: measuring is 30 % of the problem; &lt;strong>buying well&lt;/strong> is 70 %.&lt;/p>
&lt;hr>
&lt;h2 id="limits-and-traps-data-driven">Limits and traps (data-driven)&lt;/h2>
&lt;ol>
&lt;li>&lt;strong>A misleading annual average price.&lt;/strong> Using an annual average hides the 3× year-on-year volatility
and the 10× intraday range. Model scenarios, not a point.&lt;/li>
&lt;li>&lt;strong>Indexed by default.&lt;/strong> The indexed tariff is cheap on average but leaves you exposed to every
peak and every episode of manipulation. For base load, hedge it.&lt;/li>
&lt;li>&lt;strong>Ignoring the Iberian exception.&lt;/strong> It is a regulatory mechanism with an expiry date; a 36-month TCO
has to consider it changing.&lt;/li>
&lt;li>&lt;strong>Forgetting hourly carbon.&lt;/strong> Carbon and price fall at the same time in solar hours;
scheduling the shiftable work improves both axes.&lt;/li>
&lt;li>&lt;strong>Confusing wholesale with what you pay.&lt;/strong> Industrial retail adds tolls and taxes on top of
the wholesale price; use your contract price, not the pool price.&lt;/li>
&lt;/ol>
&lt;p>With the Spanish price understood, the energy track continues towards measurement tools
in depth (C3) and energy in TCO and regulation (C8). But the lesson of C2 is that, in
Spain, &lt;strong>the energy cost of AI is not decided in the GPU alone: it is decided in how you buy the
electricity in a market that is marginal-priced, volatile and watched for manipulation.&lt;/strong>&lt;/p>
&lt;h2 id="closing">Closing&lt;/h2>
&lt;p>Energy per token is a number that engineering fixes with precision, so many joules per token,
measured in a window aligned with the throughput, and that the Spanish electricity market multiplies
by a factor that changes more than 10× depending on the hour and 3× depending on the year. That second half, the
price one, hardly ever appears in technical AI articles, and it is what decides 30–50 % of the TCO
of a cluster in Spain. The price is formed in a &lt;strong>marginal-priced&lt;/strong> market where cheap renewables
are paid the price of gas, where volatility has tripled the bill in a year, and where
there are &lt;strong>final CNMC fines&lt;/strong>, Iberdrola 25 M€, Naturgy 19.5 M€, Endesa 5.8 M€, that show
that manipulation is not theoretical. For a sovereign inference platform in Spain, the
conclusion the data supports is twofold: measure energy per token rigorously, &lt;strong>and buy the
electricity with your head&lt;/strong> — a PPA or fixed tariff for the base load, solar self-consumption for the sunlight
hours, and scheduling of the shiftable work to the cheap, clean hours. Spain offers abundant sun,
growing renewables and a reasonable average carbon figure; well contracted, its energy is a competitive
advantage, and badly contracted, the biggest risk in the model. The J/token is yours to decide; the euro per
token, the market&amp;rsquo;s, unless you take it out of the market with a contract.&lt;/p>
&lt;h2 id="see-also">See also&lt;/h2>
&lt;ul>
&lt;li>&lt;a href="https://blog.lo0.es/en/posts/mlperf-power-energy-efficiency-benchmark/">MLPerf Power&lt;/a> — the standard benchmark of energy efficiency (energy per query, performance-per-watt) and its limits.&lt;/li>
&lt;li>&lt;a href="https://blog.lo0.es/en/posts/llm-energy-leaderboards-wh-per-token/">LLM energy efficiency leaderboards&lt;/a> — the J/token rankings where the data this methodology produces is published: how to read them without falling for their biases.&lt;/li>
&lt;li>&lt;a href="https://blog.lo0.es/en/posts/watt-to-carbon-pue-grid-intensity-gco2-per-token/">From the watt to carbon: PUE, grid intensity and the real cost of a token&lt;/a> — the step after measuring J/token: turning that figure into gCO₂eq and into real electricity cost with PUE and the country&amp;rsquo;s energy mix.&lt;/li>
&lt;li>&lt;a href="https://blog.lo0.es/en/posts/levers-fewer-watts-per-token-llm-inference/">Energy efficiency levers in LLM inference&lt;/a> — which levers (quantization, batching, engine, schedulers) effectively reduce the J/token this methodology measures.&lt;/li>
&lt;/ul>
&lt;h2 id="sources">Sources&lt;/h2>
&lt;ul>
&lt;li>OMIE · Operador del Mercado Ibérico de Energía — &lt;a href="https://www.omie.es/">https://www.omie.es/&lt;/a>&lt;/li>
&lt;li>OMIE · precio del mercado diario — &lt;a href="https://www.omie.es/es/market-results/daily/daily-market/day-ahead-price">https://www.omie.es/es/market-results/daily/daily-market/day-ahead-price&lt;/a>&lt;/li>
&lt;li>Energía y Sociedad · importancia y precios de OMIE — &lt;a href="https://www.energiaysociedad.es/omie-cual-es-su-importancia-para-el-sistema-electrico-espanol-y-portugues/">https://www.energiaysociedad.es/omie-cual-es-su-importancia-para-el-sistema-electrico-espanol-y-portugues/&lt;/a>&lt;/li>
&lt;li>Nada es Gratis · manipulación del precio en el mercado eléctrico español (multas CNMC) — &lt;a href="https://nadaesgratis.es/jose-luis-ferreira/manipulacion-del-precio-en-el-mercado-electrico-espanol">https://nadaesgratis.es/jose-luis-ferreira/manipulacion-del-precio-en-el-mercado-electrico-espanol&lt;/a>&lt;/li>
&lt;li>Merca2 · el precio de la luz en mayo 2026 (54 €/MWh, ×3 interanual) — &lt;a href="https://www.merca2.es/2026/05/30/precio-luz-mayo-2026-disparo-2386473/">https://www.merca2.es/2026/05/30/precio-luz-mayo-2026-disparo-2386473/&lt;/a>&lt;/li>
&lt;li>Banco de España · el sector eléctrico ante el alza del gas (renovables y precio) — &lt;a href="https://www.bde.es/f/webbe/SES/Secciones/Publicaciones/PublicacionesSeriadas/DocumentosOcasionales/23/Fich/do2316.pdf">https://www.bde.es/f/webbe/SES/Secciones/Publicaciones/PublicacionesSeriadas/DocumentosOcasionales/23/Fich/do2316.pdf&lt;/a>&lt;/li>
&lt;li>El Periódico de la Energía · normativa para liberar capacidad de red y combatir la especulación — &lt;a href="https://elperiodicodelaenergia.com/el-gobierno-ultima-una-normativa-para-liberar-la-capacidad-de-las-redes-electricas-y-combatir-la-especulacion/">https://elperiodicodelaenergia.com/el-gobierno-ultima-una-normativa-para-liberar-la-capacidad-de-las-redes-electricas-y-combatir-la-especulacion/&lt;/a>&lt;/li>
&lt;li>Fieldfisher · Real Decreto-ley 7/2026, paquete regulatorio de renovables — &lt;a href="https://www.fieldfisher.com/es-es/locations/espana/actualidad/nuevo-paquete-regulatorio-energias-renovables">https://www.fieldfisher.com/es-es/locations/espana/actualidad/nuevo-paquete-regulatorio-energias-renovables&lt;/a>&lt;/li>
&lt;li>Bird &amp;amp; Bird · almacenamiento energético en el RDL 7/2026 — &lt;a href="https://www.twobirds.com/es/insights/2026/spain/almacenamiento-energetico-real-decreto-ley-7-2026">https://www.twobirds.com/es/insights/2026/spain/almacenamiento-energetico-real-decreto-ley-7-2026&lt;/a>&lt;/li>
&lt;li>pv-magazine · caída récord de los PPAs fotovoltaicos a 32,5 €/MWh — &lt;a href="https://www.pv-magazine.es/2026/02/04/la-canibalizacion-provoca-una-caida-record-de-los-precios-de-los-ppas-fotovoltaicos-en-espana-hasta-los-325-e-mwh/">https://www.pv-magazine.es/2026/02/04/la-canibalizacion-provoca-una-caida-record-de-los-precios-de-los-ppas-fotovoltaicos-en-espana-hasta-los-325-e-mwh/&lt;/a>&lt;/li>
&lt;li>El Periódico de la Energía · PPAs solares cerca de 30 €/MWh (mitad que Francia) — &lt;a href="https://elperiodicodelaenergia.com/la-canibalizacion-acerca-el-precio-de-los-ppas-solares-a-30-mwh-en-espana-la-mitad-que-en-francia/">https://elperiodicodelaenergia.com/la-canibalizacion-acerca-el-precio-de-los-ppas-solares-a-30-mwh-en-espana-la-mitad-que-en-francia/&lt;/a>&lt;/li>
&lt;li>Energía Estratégica · cierre de la ventana de PPAs solares y el nuevo RD — &lt;a href="https://www.energiaestrategica.com/espana-atraviesa-un-cierre-de-la-ventana-de-ppas-solares-mientras-el-nuevo-real-decreto-busca-aliviar-la-industria/">https://www.energiaestrategica.com/espana-atraviesa-un-cierre-de-la-ventana-de-ppas-solares-mientras-el-nuevo-real-decreto-busca-aliviar-la-industria/&lt;/a>&lt;/li>
&lt;li>El Periódico de la Energía · la gran decisión energética de los data centers (energía firme) — &lt;a href="https://elperiodicodelaenergia.com/la-gran-decision-energetica-de-los-data-centers">https://elperiodicodelaenergia.com/la-gran-decision-energetica-de-los-data-centers&lt;/a>&lt;/li>
&lt;li>Revista Cloud · los centros de datos obligan a España a hablar de energía firme — &lt;a href="https://revistacloud.com/los-centros-de-datos-obligan-a-espana-a-hablar-de-energia-firme">https://revistacloud.com/los-centros-de-datos-obligan-a-espana-a-hablar-de-energia-firme&lt;/a>&lt;/li>
&lt;li>DCD · boom de data centers en España hacia 2026 — &lt;a href="https://www.datacenterdynamics.com/es/features/data-centers-en-espa%C3%B1a-hacia-2026-un-boom-de-90000-millones-en-proyectos/">https://www.datacenterdynamics.com/es/features/data-centers-en-espa%C3%B1a-hacia-2026-un-boom-de-90000-millones-en-proyectos/&lt;/a>&lt;/li>
&lt;/ul></description></item></channel></rss>