EU CBAM compliance is increasingly turning into a procurement problem rather than a reporting exercise. For exporters facing scrutiny over the carbon intensity of traded goods, the ability to secure verifiable low-carbon electricity attributes can determine whether EU sales remain defendable under tightening buyer requirements. In practical planning, the key variables are volume, delivery reliability and the cost of failure when the grid constrains output.
A “buyer map” built around CBAM-exposed heavy industry
A Serbia-focused planning framework groups demand for green electricity attributes around five CBAM-relevant categories that touch the country’s heavy industry: iron and steel, aluminium, fertilisers, cement, and electricity exports. Each segment has different electricity intensity and different willingness to pay for green attributes based on exposure to EU buyers, margin tightness and how much embedded emissions can be reduced through power procurement versus process change. The compliance implication is that a single generic procurement strategy is unlikely to fit all product lines.
Steel illustrates how route matters for economics. For an integrated steel route, electricity may not dominate direct emissions, but it still influences commercial outcomes because renewable procurement is increasingly treated as a gating criterion by EU buyers and because indirect emissions reductions are an early lever. Aluminium rolling and extrusion place electricity and heat inputs at the center of both unit costs and emissions narratives. Fertilisers depend on electricity directly and through gas-linked cost structures, while cement combines electricity intensity with process emissions that power alone cannot solve.
How many TWh of attributes are needed by 2028–2030
For 2028–2030, a financing-grade base case points to 1.5–2.5 TWh per year of contracted renewable attributes delivered through credible structures. A higher case reaches 3.0–4.0 TWh per year if EU customers harden supplier requirements and Serbian exporters lock in green procurement as a competitive shield. The ranges assume targeted procurement designed to reduce reportable indirect emissions and stabilise buyer confidence rather than instant full decarbonisation.
In a base case of 2.0 TWh per year, an indicative allocation across segments suggests roughly 0.6–0.8 TWh for steel and downstream metal fabrication tied to EU supply chains, 0.4–0.6 TWh for aluminium processors and metalworking clusters, 0.3–0.5 TWh for fertiliser and chemicals producers with EU exposure, 0.1–0.2 TWh for cement and building materials with export orientation, and 0.2–0.4 TWh for firm and green-label electricity export tranches or support structures providing green supply blocks to industry.
From TWh targets to MW build: why mix design affects deliverability
Turning annual targets into capacity requires assumptions about technology performance and system impact. Covering 2.0 TWh per year purely with solar typically implies about 1,200–1,400 MW of solar nameplate at a 17–19% capacity factor. That approach creates a synchronised midday volume profile that can collapse capture prices and force curtailment unless storage and exports scale alongside generation.
If the same 2.0 TWh is covered primarily by wind, the implied build is about 650–750 MW of onshore wind at a 32–38% capacity factor. Wind’s less synchronised output pattern can be absorbed with lower curtailment risk and less price cannibalisation. The most bankable structure described for attribute delivery is therefore not either/or: wind as a stability backbone paired with solar as a volume layer at strong nodes, with storage and aggregation acting as insurance against delivery shortfalls.
Cost envelope for a “firmed” supply platform
A credible base-case supply platform delivering around 2.0 TWh per year with manageable system stress is framed as 400–500 MW wind plus 400–600 MW solar, supported by 100–200 MW / 200–400 MWh of battery storage and backed by a portfolio-level aggregator that firms delivery blocks. The rationale is commercial: reducing the probability that industrial buyers pay for “green” PPAs while receiving unreliable attribute volumes due to congestion and curtailment.
CAPEX assumptions are presented as technology ranges that become decisive once grid works are included. Utility-scale solar typically lands at €0.55–0.90 million per MW in Serbia-like conditions, rising toward €0.95–1.10 million per MW where grid works are heavy. Onshore wind typically lands at €1.20–1.80 million per MW depending on civil works, access, turbine class and high-voltage distance from demand or evacuation points.
Battery systems sized for two hours commonly land at €0.35–0.55 million per MWh fully installed. Under one mixed base case—450 MW wind, 500 MW solar and 150 MW / 300 MWh batteries—the financing-grade all-in CAPEX envelope is estimated around €1.1–1.8 billion once owner costs, interconnection needs and realistic contingencies are included.
An upside case pushing toward 3.0–4.0 TWh per year—such as 700 MW wind, 800 MW solar and 200 MW / 400 MWh—moves the envelope toward €2.0–3.2 billion, driven less by turbine or module prices than by grid reinforcement intensity and the cost of building at second-tier nodes.
Returns under contracted delivery—and what curtailment does to them
Return profiles depend on whether projects operate as merchant assets or as industrial procurement infrastructure under long-term contracting structures aligned with attribute delivery needs under CBAM pressure. The most investable approach described uses long-term contracts often spanning 10–15 years with settlement terms allowing industrial buyers to treat power plus attributes as stable inputs rather than volatile trading positions.
Under those conditions, unlevered returns in the region are described as typically supporting a 7–10% band when cash flows are truly contracted and curtailment is contained. Wind is expected to show stronger resilience within that band because capture price erosion occurs more slowly with penetration and because curtailment dynamics are more event-driven than structurally synchronised like solar output at scale.
Curtailment sensitivity becomes central to underwriting because it directly reduces eligible volumes tied to CBAM-facing claims about low-carbon attributes. If the platform delivers 2.0 TWh per year, each 1% of curtailment corresponds to about 20 GWh of lost eligible volume; at an all-in green electricity value of €70–90/MWh this implies €1.4–1.8 million of annual value erosion per curtailment percentage point repeating each year.
The same framework estimates annual leakage rising from €2.8–3.6 million at 2% curtailment to €7.0–9.0 million at 5%, then €14–18 million at 10%, before considering second-order effects where remaining delivered volumes earn lower capture prices because the system saturates during peak renewable hours.
Equity IRR compression linked to curtailment levels
The impact on equity IRR is described as mechanical in conversion from lost value into project cash flows under contracted assumptions targeting an unlevered equity IRR of roughly 8–10%. Moving from 2% curtailment to 5% typically compresses IRR by about 60–120 basis points depending on debt sizing and whether curtailment is uncompensated.
A shift from 2% to 10% can compress IRR by roughly 150–250 basis points—potentially enough to push projects below institutional hurdle rates unless contracted prices are unusually strong or CAPEX is unusually low for the risk profile being taken on.
Wind-heavy portfolios are expected to show smaller IRR erosion at the same curtailment percentage because base capture prices are stronger and because curtailment tends to be more localised rather than structural across repeated hours that create chronic loss-making patterns.
Grid integration constraints: node saturation, balancing costs and delayed upgrades
The analysis highlights grid integration constraints as the largest hidden variable in any CBAM-aligned response because buyers ultimately care about delivered verifiable volumes rather than theoretical annual MWh output figures used in early planning models.
The first constraint is connection-node saturation: industrial-scale solar tends to cluster at a limited number of strong substations so marginal capacity becomes disproportionately expensive once those nodes saturate while also becoming more exposed to curtailment risk.
Other constraints include voltage and reactive-power management as recurring owner costs at scale; ramping and reserve needs where solar-heavy procurement creates steep daily ramps requiring absorption through hydro dispatch, batteries or cross-border trades; and balancing plus settlement costs where effective delivered cost includes PPA strike plus shaping plus imbalance plus replacement volumes during curtailment or outage periods—add-ons that can quietly add several euros per MWh if portfolios are not aggregated and actively managed.
Aggregation as the commercial enabler for firmed attribute delivery
This is where portfolio aggregation moves from optional optimisation into core commercial design under CBAM-facing expectations about verifiable low-carbon electricity attributes delivered reliably enough for buyer claims.
A portfolio-level aggregator can combine geographically diversified wind, node-optimised solar deployment, storage dispatch strategies and intraday repositioning to deliver firmed green blocks to CBAM-exposed industry while reducing forecast error, lowering imbalance costs and converting intermittent generation into deliverable procurement products.
For platforms delivering roughly 2.0–3.0 TWh per year, even a net improvement of €3–5/MWh from aggregation-related benefits translates into about €6–15 million of annual value—described as often determining whether projects survive downside scenarios or fail under stress conditions tied to congestion risk.
Grid upgrade slips: how delays propagate into early-year losses
The stress test flagged in planning focuses on grid-upgrade slip of 12–18 months rather than total system failure across all assets in a portfolio programme.
The failure mode in portfolio structures is described as partial delay where some nodes lag while others proceed; if planned capacity totalling around 300 MW is delayed by 18 months, deferred generation could reach roughly 700–1,000 GWh depending on whether it is wind- or solar-heavy output being postponed.
At €70–90/MWh this equates to €49–90 million of postponed revenue and attribute delivery concentrated in early years when financing carry costs and contract milestones matter most; equity IRR impacts are described as compressing by about 100–200 basis points in a disciplined base case and about 150–250 basis points in an aggressive upside case when delays coincide with increased grid CAPEX needs or forced merchant exposure.
Compliance implications across steel, aluminium, fertilisers, cement—and hydrogen-linked decarbonisation pathways
The practical conclusion drawn from these figures is that CBAM-exposed exporters cannot treat green electricity as a generic “PPA at the lowest strike.” They need portfolio solutions capable of delivering dependable attribute volumes under real grid constraints across sectors including cement, steel, aluminium and fertilisers—alongside electricity exports where interconnection economics can be decisive—and any hydrogen-related decarbonisation plans that rely on credible low-carbon power inputs.
For EU importers evaluating supplier claims under CBAM-linked scrutiny while operating within EU ETS dynamics under the broader European Green Deal policy architecture, these numbers underline why contract settlement terms must align with delivery reliability rather than only headline pricing.
For EU producers competing against imports from high-electricity-intensity supply chains, the same analysis suggests competitive pressure will increasingly shift toward those able to demonstrate verifiable low-carbon electricity attributes backed by firming structures resilient to curtailment patterns and grid-delivery timelines during both planning cycles leading up to compliance reporting requirements associated with CBAM implementation phases.

