Working Paper · Energy Economics

Electricity Market Structure and Consequences for Wind and Solar Uptake in the EU-27

AUTHORS Grafström · Halvarsson · Herold · Vinberg
COVERAGE EU-27 · 2000–2022
FUNDING Swedish Competition Authority
METHODS Panel FE · AB-GMM · Bias Correction

Does market concentration impede renewable deployment?

This paper examines whether concentration in electricity generation affects the deployment of wind and solar capacity across the 27 European Union member states over 2000–2022. Market concentration is measured by the generation share of the largest electricity producer, and deployment is measured as installed wind and solar capacity relative to total national capacity.

Using dynamic estimation methods that account for persistence, unobserved heterogeneity, and reverse causality, the analysis finds no systematic relationship between market concentration and subsequent wind or solar deployment — a result robust across alternative measures, bias-corrected estimators, balanced samples, and extensive heterogeneity analyses.

Core finding
Within the EU institutional setting, market concentration per se is not a first-order constraint on renewable uptake.
Deployment is primarily driven by policy settings — particularly feed-in tariffs — and by the path dependence inherent in installed capacity. This cautions against extrapolating country-specific findings to EU-wide policy conclusions.
27
EU Member States
Annual country-level panel drawn primarily from Eurostat and the European Commission, 2000–2022.
23yr
Time Span
One of the first harmonized EU-wide assessments spanning more than two decades of energy transition.
32%
Wind + Solar Share by 2022
Up from 1.5% in 2000. Wind at 15.7%, solar at 16.3% of total installed capacity.
55%
Average Largest Producer Share
Ranging from 24% (Finland) to 88% (Cyprus), reflecting wide cross-country variation in market structure.
EU-27 average renewable capacity share (wind + solar) — selected years
2000
1.5%
2005
3.9%
2010
7.8%
2015
17.4%
2020
25.5%
2022
32.0%

Source: Eurostat / European Commission. Own calculations.

Effect of market concentration on renewable deployment

The table below reports estimates across pooled OLS, fixed-effects OLS, and Arellano–Bond GMM, for both the full sample and a bias-corrected balanced panel following Chen et al. (2019). The coefficient of interest is the lagged market share of the largest producer (MSt−1).

Base Sample Balanced Sample
Dependent variable: Renewable sharet (1) OLS (2) FE-OLS (3) AB-GMM (4) FE-OLS (7) FE-OLS (8) AB-GMM
Renewable sharet−1 1.016***(0.010) 1.003***(0.021) 0.747***(0.087) 0.996***(0.023) 0.823***(0.087)
Market sharet−1 (MSt−1) — key coefficient −0.003(0.003) 0.006(0.007) −0.006(0.025) −0.063***(0.019) 0.007(0.013) −0.010(0.025)
Observations 515515485516 399378
AR(2) p-value 0.152 0.115
Bias correction [bootstrapped SE] 0.003 [0.033] 0.049 [0.058]

All models include full sets of country and year fixed effects. Column (4) excludes the lagged dependent variable — its significant negative coefficient cannot be interpreted causally due to dynamic panel bias. Robust standard errors in parentheses. *** p<0.01.


What does drive renewable deployment?

Path Dependence

The strongest predictor is lagged renewable share — deployment is self-reinforcing through accumulated know-how, supply chains, and learning-by-doing.

Feed-In Tariffs

The only policy variable consistently significant across FE-OLS and AB-GMM specifications. Support scheme design matters more than market structure.

Regional Catch-Up

Eastern and Western Europe show more positive within-country concentration slopes than Northern Europe — reflecting deployment acceleration despite incumbent dominance.

Not Market Structure

Concentration, unbundling, competitive market rules, independent power producers, and fossil fuel subsidies all yield null or fragile effects.

Empirical strategy

The baseline specification is a dynamic panel model with country and year fixed effects, estimated to address endogeneity from reverse causality between concentration and renewable deployment. The dynamic structure captures the strong persistence in renewable capacity stocks.

RSit = α · RSit−1 + γ · MSit−1 + x′it−1β + δt + ci + εit
RS = renewable share (wind + solar, % of installed capacity)  ·  MS = largest producer market share  ·  ci = country FE  ·  δt = year FE

Estimators

Pooled OLS, Fixed Effects OLS, and Arellano–Bond (1991) GMM. Triangulated to guard against dynamic panel bias and instrument proliferation.

Bias Correction

Split-sample bias-correction following Chen, Chernozhukov & Fernández-Val (2019) on a balanced panel of 21 countries, with bootstrapped standard errors.

Identification

Lagged levels as internal instruments under Arellano–Bond orthogonality conditions. AR(1)/AR(2) and Hansen tests reported throughout.

Robustness

Alternative outcome variables (solar/wind separate, log capacity, incl. hydro), alternative concentration proxies, 5-year interval data, and retail-market measures.

Replication & Data

This paper comes with a fully reproducible Python pipeline alongside the original Stata code. Data is publicly available from Eurostat, the European Commission, World Bank, and OECD.

GitHub Repository

Full data, cleaning scripts, analysis code, and output tables. The Python replication uses linearmodels for panel estimation, with the original Stata do-files preserved for reference.

Python linearmodels pandas Stata panel FE AB-GMM EU-27
View on GitHub → Download Paper

Primary Data

Eurostat installed capacity. European Commission electricity market pocketbook. Annual, 2000–2022.

Market Structure

World Bank Global Power Market Structure Database (GPMSD). Regulatory regime classifications.

Policy Variables

OECD feed-in tariff database (wind + solar, USD/kWh). OECD fossil fuel support as % of GDP.

Macroeconomic

World Bank: GDP per capita, natural resource rents. European Commission: electricity consumption, net imports.

Jonas Grafström
Luleå University of Technology
The Ratio Institute jonas.grafstrom@ltu.se
Daniel Halvarsson
The Ratio Institute daniel.halvarsson@ratio.se
Theo Herold
Hanken School of Economics
Helsinki GSE · Ratio Institute theo.herold@hanken.fi
Nadja Vinberg
The Ratio Institute

Financial support from the Swedish Competition Authority (Konkurrensverket) is gratefully acknowledged.