5.1. Comparative Analysis at the National Level
5.1.1. Descriptive Statistics of the Principal Variables
Table 2 presents the descriptive statistics of the principal variables for the entire panel of 320 observations.
The panel is characterised by considerable heterogeneity. Sectoral gross value added ranges from 87.7 million euros (mining and quarrying in Croatia) to over 277 billion euros (manufacturing in Italy), which reflects the different economic scales of the observations included. The mean value of eco-investment is 176.4 million euros per observation, with the standard deviation more than twice the mean, indicating a highly skewed distribution influenced by the large economies. Eco-expenditure is on average approximately four times higher than eco-investment (736.4 compared with 176.4 million euros), which suggests that within the sample, enterprises direct considerably more resources towards the current consumption of environmental services than towards capital outlays for environmental protection. The median I/E ratio of 0.58 confirms this pattern at the observation level - in more than half of the observations by country, sector and year, expenditure exceeds investment.
5.1.2. National Profiles
Table 3 presents the mean annual values of eco-investment, eco-expenditure and their ratio for each country, aggregated across all four sectors. The countries are ranked by the I/E ratio.
A clearly pronounced dominance of the expenditure-oriented model is observed. Eight of the ten countries have an I/E ratio below 0.8, which means that their current environmental expenditure significantly exceeds capital investment in environmental protection. Only Estonia (I/E = 1.46) and Slovenia (I/E = 0.87) approach or surpass equilibrium between the two types of environmental efforts.
The variation in the absolute and relative levels of environmental efforts is also substantial. Austria allocates the largest share of GDP to eco-expenditure (1.19%), followed by Spain (0.60%) and Italy (0.45%). By contrast, eco-investment as a share of GDP is comparatively low across all countries, ranging from 0.054% (Italy) to 0.407% (Slovenia). These results show that in the countries under consideration, environmental protection efforts are directed predominantly towards current expenditure rather than towards capital investment in cleaner technologies or pollution abatement infrastructure.
5.1.3. Dynamics over Time
Table 4 presents the total values of eco-investment and eco-expenditure (sum across the four sectors) at the beginning and at the end of the period under review, together with the percentage change.
During the period 2015-2022, two distinct development trajectories stand out. With regard to environmental expenditure, almost all countries record real growth. The only exception is Croatia. The strongest growth is registered by Austria - +879%. This result, however, is partly attributable to a structural break in the reporting methodology in 2018. The remaining countries show more moderate growth, ranging from 23% in France to 134% in Slovenia.
With regard to environmental investment, the picture is considerably more heterogeneous. Five countries - Austria, Spain, Slovenia, Belgium and France - increase their real eco-investment during the period. The largest growth is in Austria (+198%) and Spain (+152%). At the same time, five other countries record substantial declines. These are Romania (−81%), Estonia (−72%), Italy (−62%), Croatia (−54%) and Bulgaria (−17%).
This divergence points to a growing separation between two groups of countries. The first group comprises those that are expanding capital investment in environmental protection. The second comprises those in which investment is declining despite an increase in current expenditure. The latter pattern - rising expenditure accompanied by simultaneously declining investment - may be interpreted as a shift from transformational to sustaining environmental strategies. This is observed in a number of countries in Eastern and Southern Europe.
5.2. Sectoral Analysis
5.2.1. Sectoral Profiles
Table 5 presents the mean values of the intensity of eco-investment and eco-expenditure by sector, averaged across all ten countries for the period 2015-2022. The four sectors are characterised by substantially differing profiles of environmental efforts.
Agriculture stands out as the sector with the highest expenditure intensity. Eco-expenditure amounts to an average of 16.75% of sectoral gross value added. This value is an order of magnitude higher than that in the remaining three sectors. It reflects the substantial costs borne by agricultural enterprises for environmental protection services, including waste management, water purification and compliance with environmental regulations. By contrast, the intensity of eco-investment in agriculture is considerably lower - 2.34% of GVA. This yields an approximate I/E ratio of 0.14, which is the lowest among the sectors under consideration. In this sense, agriculture emerges as a typical sector with a sustaining model of environmental strategy.
The electricity sector presents the most balanced profile. The intensity of eco-investment in this sector is 2.24% of GVA, whilst the intensity of eco-expenditure is 2.11% of GVA. This is the only sector in which, on average, capital investment in environmental protection matches or exceeds current expenditure. This result corresponds to the capital-intensive nature of the energy sector and to the ongoing investment in emissions reduction, particularly in the areas of air pollution control and wastewater management.
Manufacturing accounts for the largest absolute volumes of both investment and expenditure. Nevertheless, it exhibits the lowest relative intensities - 0.50% and 0.91% of GVA, respectively. The large economic scale of the sector leads to a “dilution” of environmental efforts when they are expressed as a share of value added. Mining and quarrying is characterised by moderate intensity values - 1.19% and 1.49% of GVA - and displays a near-equilibrium between investment and expenditure.
5.2.2. Cross-Country Differences in Sectoral Investment Intensity
Table 6 presents the distribution of eco-investment intensity by country and sector, revealing considerable heterogeneity behind the averaged sectoral values.
The cross-country differences within individual sectors are substantial. In agriculture, Belgium directs 9.92% of sectoral gross value added towards eco-investment. This is considerably more than the next country - Slovenia at 5.52%. At the same time, Spain records zero values. In the electricity sector, Slovenia (8.51%) and Estonia (5.38%) invest at levels that are several times higher than the sample average. This reflects the importance of environmental compliance in the energy sector in smaller economies with a concentrated production structure. In manufacturing, the variation is more limited, ranging from 0.16% to 1.03%. This suggests more homogeneous behaviour across countries with regard to environmental investment in this sector. In mining and quarrying, Romania stands out with an investment intensity of 4.41%. This value is driven by investment directed towards environmental compliance in the extractive sector.
5.2.3. Cross-Country Differences in Sectoral Expenditure Intensity
Table 7 presents the corresponding values of eco-expenditure intensity.
The intensity of expenditure in agriculture reveals particularly large differences between countries. Austria records an average of 71.02% of sectoral gross value added directed towards eco-expenditure. This value probably reflects both the structural break in 2018 and the broad scope of environmental services utilised in Austrian agriculture, including a significant share of organic production and costs for agro-environmental compliance. Belgium (28.65%), Spain (18.82%), France (16.01%) and Italy (16.21%) also record high levels of expenditure intensity in agriculture. By contrast, Estonia (0.12%) and Croatia (0.16%) show negligibly low values. These differences may be partly explained by differences in national reporting methodologies and by differences in the scope of activities classified as environmental protection services.
In the electricity sector, Slovenia (9.86%) and Romania (6.66%) stand out with high expenditure intensity. By contrast, Belgium (0.10%) and Spain (0.24%) record minimal values in this sector. These differences probably reflect variations in the energy mix, the age of the production infrastructure and the extent to which environmental protection costs are borne internally by the energy sector.
5.2.4. Investment-to-Expenditure Ratio by Country and Sector
Table 8 presents the I/E ratio for each country-sector combination, providing the most detailed view of the orientation of environmental efforts.
Table 8 shows that the orientation of environmental efforts varies to the same extent within individual countries as between them. For example, Austria is clearly expenditure-oriented in agriculture (I/E = 0.01) and manufacturing (0.24), but strongly investment-oriented in the electricity sector (17.39). In a similar manner, Estonia combines a high investment orientation in electricity (13.80) and agriculture (4.32) with an expenditure-oriented model in manufacturing (0.38). This within-country variation underscores the importance of sectoral disaggregation - national averages conceal substantially differing environmental strategies at the sectoral level.
In cross-sectoral terms, a clear pattern emerges. Agriculture is dominated by expenditure in most countries, with the exception of Croatia (5.15) and Estonia (4.32). The electricity sector is more investment-oriented, with six of the nine countries recording an I/E ratio above unity. Manufacturing is predominantly expenditure-oriented, with only Bulgaria (1.85) and Slovenia (1.00) reaching or exceeding equilibrium between investment and expenditure. Mining and quarrying presents a mixed picture, with ratios ranging from 0.03 (Croatia) to 2.65 (Estonia).
5.3. Towards a Typology of Environmental Strategies
On the basis of the results from the preceding sections, this part proposes a typology of environmental strategies built upon two dimensions - the intensity of eco-investment and the intensity of eco-expenditure, measured as a share of gross value added. The aim of this typology is not to rank countries normatively but to reveal differences in the structure of environmental efforts and in the prevailing orientation of environmental behaviour.
The typology is derived directly from the conceptual distinction already introduced between environmental investment and environmental expenditure. The joint examination of the two indicators makes it possible not only to assess the level of environmental efforts but also to identify their internal profile. In this way, it becomes apparent whether the environmental strategy is oriented to a greater extent towards transformation and expansion of capacity, or towards the maintenance of current environmental functioning and compliance.
For each country, the mean value for the period 2015-2022 was calculated for both indicators - the intensity of eco-investment and the intensity of eco-expenditure. On this basis, the countries were positioned within four quadrants defined by the median values of the sample. The use of the median is of a pragmatic and analytical nature - it allows a clear distinction between relatively high and relatively low values whilst at the same time limiting the influence of extreme observations. In this sense, the proposed classification should be regarded as relative to the specific sample and as an interpretive tool rather than as a universal scheme with fixed boundaries.
5.3.1. Conceptual Logic of the Typology
The combination of the two dimensions - the intensity of eco-investment and the intensity of eco-expenditure - makes it possible to distinguish four principal strategic profiles.
The first profile encompasses countries with high intensity in both dimensions. Here, environmental efforts combine substantial current expenditure with active investment in new capacity, which is why this quadrant may be defined as a model of active transformation.
The second profile includes countries with high investment but low expenditure intensity. In these countries, the environmental orientation is more strongly directed towards capital construction and modernisation than towards current maintenance, which is why this model is defined as investment focus.
The third profile is characterised by high expenditure but low investment intensity. It reflects a dominance of current environmental compliance activities and the maintenance of existing systems, without a corresponding expansion of capacity. This quadrant is defined as a sustaining model.
The fourth profile includes countries with low intensity in both dimensions. Here, environmental efforts are limited in both current and investment terms, which is why this model is designated as passive.
5.3.2. Characterisation of the Four Quadrants
Quadrant 1: Active Transformation (high investment, high expenditure). Slovenia, Belgium and France combine above-median intensities in both dimensions, which distinguishes them as the countries with the highest overall intensity of environmental efforts in the sample. This profile implies the simultaneous maintenance of substantial current expenditure on environmental services and active investment in environmental protection capacity. Among the three countries, Slovenia displays the most balanced model, with an I/E ratio of 0.87, indicating a relative equilibrium between the investment and expenditure components. Belgium and France also fall within this quadrant, but their environmental profile is more clearly expenditure-oriented, with I/E ratios of 0.49 and 0.48, respectively. This means that even within the group of the most active countries, current expenditure remains higher than capital investment. Consequently, belonging to the active transformation quadrant does not signify investment dominance but rather high intensity in both indicators. The position of these countries may be linked to comparatively developed environmental policy frameworks, which simultaneously create sustained pressure for compliance and incentives for long-term investment in environmental infrastructure and cleaner technologies.
Quadrant 2: Investment Focus (high investment, low expenditure). Romania and Estonia are distinguished by above-median eco-investment intensity coupled with below-median eco-expenditure intensity. This profile points to an environmental strategy in which capital outlays carry greater weight than the current maintenance of existing systems. In both countries, the high investment intensity is concentrated in specific sectors. In Estonia, it is associated primarily with the electricity sector, whilst in Romania it is linked to mining and quarrying. This shows that the investment focus does not stem from evenly distributed environmental efforts but from specific sectoral needs and regulatory requirements. At the same time, the dynamic analysis reveals a sharp decline in real eco-investment during the period 2015-2022 - by 72% in Estonia and by 81% in Romania. This calls into question the sustainability of this model and suggests that the classification reflects a residual effect of an earlier investment cycle rather than a durably established strategic orientation. Should this trend persist, both countries could shift towards a more passive environmental profile.
Quadrant 3: Sustaining Model (low investment, high expenditure). Austria and Spain are characterised by above-median eco-expenditure values and below-median eco-investment values. This delineates a profile of environmental orientation dominated by the current functioning of existing environmental protection systems. The I/E ratios are the lowest in the sample - 0.08 for Austria and 0.09 for Spain. This means that capital investment represents less than one-tenth of current expenditure - a pronounced disproportion that has no analogue in the other quadrants. In the case of Austria, this profile is strongly influenced by the exceptionally high expenditure intensity in agriculture - 71.02% of GVA. Before 2018, Austrian agricultural eco-expenditure was approximately 150 million euros per year. After 2018, it rose to over 5 billion euros. This probably reflects a fundamental change in the scope of classified activities, including agro-environmental payments and a broader spectrum of environmental services, rather than an actual tenfold increase in operational costs. In the case of Spain, the profile is shaped by more evenly distributed but likewise substantial expenditure intensities, which are particularly visible in agriculture, where they reach 18.82% of GVA. The sustaining model admits a dual interpretation. On the one hand, it may reflect mature environmental systems that have already been constructed and are functioning effectively. In such a situation, the need for new capital outlays is objectively lower. On the other hand, this model may signal a structural deficit of investment in the renewal and modernisation of environmental infrastructure. In the long term, this could lead to the ageing of existing systems and a decline in their effectiveness. Distinguishing between the two interpretations requires additional information that lies beyond the scope of the present study, including data on the age and technical condition of environmental infrastructure, as well as on the specific policy instruments that determine the balance between current expenditure and capital investment.
Quadrant 4: Passive Model (low investment, low expenditure). Bulgaria, Italy and Croatia are characterised by below-median values in both dimensions. This positions them as the countries with the most limited relative environmental efforts in the sample. This profile does not necessarily signify a disregard for environmental concerns in absolute terms - this applies particularly to Italy, which is the third largest economy in the sample and generates substantial absolute volumes of eco-investment and eco-expenditure. The position in this quadrant rather reflects the fact that when environmental efforts are related to the economic scale of the respective sectors, these three countries allocate relatively fewer resources compared with the rest.
The position of Italy is particularly illustrative. The intensity of eco-investment is 0.85% of GVA, whilst the intensity of eco-expenditure is 4.57% of GVA. Both indicators remain below the median values for the sample, despite the fact that in absolute terms Italian eco-expenditure, averaging 7,651 million euros per year, is the second highest after France. This case illustrates an important methodological feature: the absolute size of environmental efforts and their relative intensity may lead to substantially different classifications. This underscores the need for analysis of both dimensions. Bulgaria and Croatia, as smaller economies, show limited environmental efforts in both absolute and relative terms. Bulgarian eco-investment intensity is 1.04% of GVA - immediately below the median threshold of 1.315%, which makes the country a borderline case. With a slightly higher investment intensity, Bulgaria could be reclassified into Quadrant 2. Croatia shows the lowest values in the sample in both dimensions - 0.47% for investment and 1.55% for expenditure - which positions it furthest from the active transformation model. The dynamic analysis further compounds the picture for this quadrant. All three countries record a decline in real eco-investment during the period 2015-2022. The decrease is 62% for Italy, 54% for Croatia and 17% for Bulgaria. At the same time, eco-expenditure grows moderately - by 27% for Italy and 33% for Bulgaria - or declines slightly - by 9% for Croatia. This pattern, in which investment contracts whilst expenditure remains stable or grows, may be interpreted as a gradual transition from residual investment activity to an entirely sustaining regime. Should this trend persist, it raises concerns about the long-term capacity of these countries to modernise their environmental infrastructure and to meet the growing requirements of European environmental policy, including the objectives of the European Green Deal.
5.3.3. Sectoral Typology
The same analytical logic may be applied at the sectoral level. When averaged across all ten countries, the four sectors under consideration occupy clearly distinct positions in the investment-expenditure space. Agriculture falls consistently within the sustaining model quadrant, displaying the highest expenditure intensity - 16.75% of GVA - coupled with moderate investment intensity - 2.34%. This confirms that in this sector, environmental efforts are oriented primarily towards current maintenance and compliance.
The electricity sector is closest to the active transformation quadrant, with comparatively balanced values of eco-investment and eco-expenditure - 2.24% and 2.11% of GVA, respectively. This profile is consistent with the capital-intensive nature of the sector, the high degree of regulatory pressure and the need for technological modernisation.
Manufacturing falls within the passive quadrant, with the lowest values in both dimensions - 0.50% for investment and 0.91% for expenditure. This result is particularly important, as it shows that the significant environmental footprint of the sector in absolute terms does not necessarily translate into high relative environmental intensity. A “dilution” effect, generated by the large value added, is probably at work here.
Mining and quarrying occupies an intermediate position with moderate values - 1.19% for investment and 1.49% for expenditure. It does not display a clearly pronounced predominance of either component but remains closer to a balanced profile than to an extreme dominance of expenditure or investment.
The sectoral typology confirms that environmental efforts are highly unevenly distributed across the economy. Sectors with high capital intensity and concentrated sources of pollution, such as electricity and mining and quarrying, are more inclined towards more balanced or investment-oriented profiles. By contrast, sectors with dispersed impacts and high current compliance costs, such as agriculture, are dominated by the expenditure component. In this way, the sectoral analysis further develops the national typology and shows that the structure of environmental efforts depends to a considerable extent on the technological and regulatory characteristics of the specific industry.
5.3.4. Limitations of the Typology
The proposed typology has analytical value but should be interpreted with several important caveats. First, the boundaries between quadrants are defined on the basis of the median values within the specific sample. This means that the classification is relative rather than absolute. Should the composition of the sample change, the median thresholds would also change, which could lead to the reclassification of certain borderline cases. Second, the typology is based on mean values for the entire period 2015-2022 and therefore does not capture within-period dynamic changes. It is possible for a given country to have an investment-oriented average profile whilst at the same time recording a decline in investment towards the end of the period. Third, the indicator used for eco-expenditure covers the intermediate consumption of environmental protection services and does not encompass all possible forms of current environmental expenditure. Consequently, the expenditure dimension may be partially underestimated for some countries and sectors. Fourth, the typology is of a descriptive and interpretive rather than normative nature. It does not presuppose that one quadrant is by definition superior to another. The optimal ratio between eco-investment and eco-expenditure depends on a range of factors, including the degree of development of environmental infrastructure, the sectoral structure of the economy, the phase of technological adaptation and the specific design of public policies.