Environmental and technological determinants of organization
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Environmental Policy Stringency and Technological Innovation:
Evidence from Patent Counts
by
Ivan Hascic‡, Nick Johnstone
‡ and Christian Michel
†
May 7th, 2008
Abstract
This paper examines the impact of public environmental policy, as reflected in expenditures on
pollution abatement and control, on innovations in environment-related technology. The analysis is
conducted using patent data for a panel of 16 countries between 1985 and 2004. It is found that
there are important differences in innovation effects of resources spent in the public vs. private
sector and resources spent on pollution control activities vs. directly on R&D. These results are
broadly confirmed with a subsequent analysis on a broader cross-section of 33 countries over the
period 2001-2006, using an alternative measure of environmental policy stringency.
JEL codes: O31; O38; Q55; Q58
Keywords: Environmental Policy; Technological Innovation; Patents
‡ [email protected], [email protected] Empirical Policy Analysis Unit, OECD Environment
Directorate, 2 rue André Pascale, 75775 Paris Cedex 16, France
† Department of Economics, Oxford University, Manor Road, Oxford, United Kingdom
1
1. Introduction
There is currently much interest in the role of public policy in inducing innovations in technologies
which help reduce environmental impacts of economic activity. In many industrialized countries,
significant progress has been achieved during the past several decades on this front. For example,
emissions of pollutants into air and water have been greatly reduced1 and some advances have been
achieved in waste management.2 Most likely, this has been achieved due to structural changes in
economic activity (e.g., less emission-intensive production such as coal fired power plants), input
substitution (e.g., using coal with lower sulphur content), as well as via technological
improvements (incl. end-of-pipe solutions such as scrubbers, or production process innovations
such as fluidized bed combustion).
Understanding the factors that have determined this process is important for several
reasons. First, despite significant progress achieved to date, air and water pollution remains an
important public policy issue due its negative impacts on human health (see e.g., Cohen et al. 2005)
and ecosystem functions (see e.g., Islam and Tanaka 2004 and Lorenz 1995). Moreover, further
emissions reductions will require action on the part of more diffuse sources of pollution and may
therefore be more difficult to achieve, as their identification and measurement are complicated.
Finally, while emissions of many “traditional” pollutants are currently more-or-less controlled, new
“emerging” pollutants may become relatively more important in the future. In this context,
technological innovation is important because it allows society to further reduce environmental
impacts or to achieve a given environmental goal at lesser cost (see e.g., Kneese and Schultze
1977).
1 Between 1990 and 2005, emissions of SOx and NOx have fallen by 72% and 33% respectively in the
European Union (EU15) and 37% and 26% in the US. In some OECD countries emissions have actually
increased, notably in Australia and New Zealand with 25%-58% increase in emissions. Emissions causing
increased levels of water pollution have also been reduced in many countries. For example, the proportion of
population connected to public wastewater treatment plants has increased from 46% to 68% in OECD
countries during the last 25 years. However, enormous differences remain across countries – while as much
as 98% of population is connected in the Netherlands and the UK, the share is only 35% in Mexico and
Turkey (OECD 2007a). 2 Between 1990 and 2005, the volume of municipal waste generated per capita has remained stable in the US
(750 kg), had dropped slightly in Japan (from 410 to 400 kg), and has increased sharply in the European
Union (EU15) (from 430 to 570 kg) (OECD 2007a).
2
In the last several decades, OECD countries have introduced a number of policy measures
with the objectives to reduce environmental impacts of economic activity. However, it is difficult
to predict the effect of such policies on the pattern of technological innovation. While private (firm-
level) incentives to environment-friendly innovations may play some role3, it is public policy that
often plays the pivotal role in creating demand for technological innovation in environment-related
technologies, although its impact may vary across countries, pollutants, and over time.
In 1932, John Hicks observed that a change in the relative prices of factors of production
will motivate firms to invent new production methods in order to economise the use of a factor
which has become relatively expensive. This idea, originally developed in the context of labour
economics, came to be known as the “induced innovation hypothesis”. Applied to the public policy
framework, this implies that if governments could affect relative input prices, or otherwise change
the opportunity costs associated with the use of environmental resources, firms‟ incentives to seek
improvements in production technology would be increased. Indeed, since markets often fail to put
a price on environmental resources, the price of many environmental assets is to a large extent
formed by government regulation. Depending on the stringency of a regulation, the change in
opportunity costs of pollution then translates into increased cost of some factors of production.
Since this effect is unobservable to a researcher, pollution abatement and control expenditure
(PACE) can serve as an imperfect proxy for the changes in opportunity costs involved.
PACE has been used to examine the links between environmental regulation and
innovation in two distinct manners. In one case, the focus has been on the effects of PACE
expenditures on (plant-, sector-, or country-level) differences in productivity growth by examining
whether a given level of PACE has more or less greater impact on productivity (e.g., Gray and
Shadbegian 2003; Morgenstern, Pizer and Shih 2001; Jorgenson and Wilcoxen 1990; Gollop and
Roberts 1983; see also Jaffe et al. 1995 and papers cited therein). The basic question is whether, the
impact of a given level of PACE on productivity is more or less than unity. For instance, some
investments targeted at reducing environmental impacts may increase (or decrease) the efficiency
3 For instance, recycling of secondary materials to reduce input costs, consumer demand for „defensive‟
measures, etc.
3
associated with the use of other factors of production in production more generally (see Labonne
and Johnstone 2007 for discussion on this issue; see also Morgenstern, Pizer and Shih 2001).
In the second case, the focus has been on the effects of PACE on one aspect of productivity
– notably technological innovation, using patent data (e.g., Popp 2003; Brunnermeier and Cohen
2003; Jaffe and Palmer 1997; Lanjouw and Mody 1996). However, empirical evidence on the
effect of stringency of environmental policy on innovative behaviour remains limited, both with
respect to the overall effects of environmental policy on technological innovation, as well as the
more specific question of the extent to which this is reflected in patent activity. Nevertheless, there
is now increasing empirical evidence to support the contention that environmental policies do lead
to technological innovation. For recent reviews of the empirical literature on this theme see
Vollebergh (2007) and Jaffe, Newell and Stavins (2002).
This paper continues in the tradition of the latter approach and studies the effects of public
environmental policy (as proxied by PACE) and other factors on innovation in environmental
technologies, using patent data for an unbalanced panel of 16 countries for the period 1985-2004.
Unlike previous studies which used PACE at the sectoral level, this is the first econometric study
using PACE data at the cross-country level.4 The key hypothesis to be explored is the effect of
public environmental policy on innovation; and in particular, the possibly differential effect across
the alternative economic sectors undertaking PAC activities (i.e. public sector, private sector,
specialized producers). The role of government environmental R&D is also examined.
2. Data construction and interpretation
2.1. Patent counts as a measure of environment-related innovation
Patent data have been used as a measure of technological innovation because they focus on outputs
of the inventive process (Griliches 1990). This is in contrast to many other potential candidates
(e.g. research and development expenditures, number of scientific personnel, etc.) which are at best
imperfect indicators of the innovative performance of an economy since they focus on inputs.
4
Moreover, patent data provide a wealth of information on the nature of the invention and the
applicant, the data is readily available (if not always in a convenient format), discrete (and thus
easily subject to statistical analysis), and can be disaggregated to specific technological areas.
Significantly, there are very few examples of economically significant inventions which have not
been patented (Dernis and Guellec 2001).
However, patents are an imperfect measure of technological innovation for several reasons.
First, there is variation in the propensity for inventors to patent across countries and sectors. This is
due in part to the level of protection afforded by the patent, but also to the possibility of
appropriating rents from innovation by other means depending upon market conditions (e.g.,
industrial secrecy). In the empirical section of this paper, this concern over differences in the
propensity to patent is addressed by including a variable reflecting the overall patenting activity to
control for these effects across countries and over time.
Second, it is difficult to distinguish between the „value‟ of different patents on the basis of
patent applications. Most clearly, the use of unweighted patent counts would attribute the same
importance to patents for which there were no successful commercial applications with those which
are highly profitable. In this paper, this concern is addressed by using data on patent applications to
the European Patent Office (EPO), rather than individual patent offices.5 Through the EPO, the
applicant designates as many of the EPO member states for protection as it desires, rather than
applying to individual European patent offices among the 32 contributing countries. If the
application is successful, the patent is transferred to the individual national patent offices
designated for protection in the application. Given that EPO applications are more expensive than
applications to national patent offices, inventors typically first file a patent application in their
home country, and then apply to the EPO if they desire protection in multiple European countries
due to perceived market opportunities. As such, patent applications to the EPO are likely to be of
greater commercial value than the mean value of patent applications at national patent offices.
4 It is important to study these effects in a cross-country manner because large differences in per capita
emissions across countries exist (e.g., Australia‟s SOx emissions are almost 5-times higher than the OECD
average (OECD 2007a)).
5
While the use of EPO applications introduces a „quality‟ threshold to ensure that only
relatively valuable patents are included in the analysis, it introduces a potential source of bias.
While the European market is significant, it is still expected that there will be some bias toward
applications from European inventors (see Dernis and Guellec 2001). For a given invention, a
German inventor will be more likely to patent at the EPO than an American inventor. In the
empirical analysis undertaken in this study the bias associated with the use of EPO applications is
addressed through the inclusion of both country fixed effects and a control variable reflecting data
on total EPO applications by inventor country for all technology areas.
And finally, it can be difficult to identify relevant patent applications. Drawing upon
existing efforts to define „environmental‟ activity in sectoral terms, some previous studies have
related patent classes to industrial sectors using concordances (e.g., Jaffe and Palmer 1996). The
weaknesses of such approach are twofold. First, if the industry of origin of a patent differs from
industry of use of the patent, then it is not clear to which industrial sector a patent should be
attributed in the analysis. This is important when studying specifically “environmental” technology
because in this case the demand (users of technology) and supply (inventors of technology) of
environmental innovation may involve different entities. Often, “environmental” innovations
originate in industries which are not specifically environmental in their focus. For example,
technologies aimed at reducing wastewater effluents from the pulp & paper industry are often
invented by the manufacturing or chemicals industry (see e.g., Popp et al. 2007). On the other hand,
some “environmental” industries invent technologies which are widely applicable in non-
environmental sectors (e.g., processes for separation of packaging waste; separation of vapours and
gases).
More fundamentally, sectoral classifications are, by definition, based on commercial
outputs. As such there will be a bias toward the inclusion of patent applications from sectors that
produce environmental goods and services. The application-based nature of the patent
classification systems allows for a richer characterisation of relevant technologies. Consequently,
5 Using data on application, rather than granted patents, is more useful for international comparisons because
granting frequency varies across countries and over time (see e.g., Griliches 1990).
6
in this study patent classifications are used, rather than those of industrial or sectoral
classifications.6 Specifically, relevant patents were identified using the International Patent
Classification (IPC) system. However, IPC classes may be too broad for many areas of
“environmental” technology, leading to two possible types of error when searching for relevant
patents – inclusion of irrelevant patents and exclusion of relevant patents from the selected
classifications. Therefore keyword searches were used to filter only the relevant patents.
Patent data were extracted from the OECD Patent Database (OECD 2007b) using a search
algorithm based on a selection of IPC classes combined with keyword searches to target specific
areas of environment-related technology (Annex 1 gives the list of classes included; for the
complete search strategy see Schmoch 2003).7 The patent data are used to construct counts of
patent applications to the EPO in selected areas of environmental technology (air pollution, water
pollution, waste disposal, noise protection, and environmental monitoring), classified by inventor
country (country of residence of the inventor) and priority date (the earliest application date within
a given patent family). A panel of patent counts for a cross-section of all countries and over a time
period of 27 years (1978-2004) was obtained. Figure 1 shows the total number of EPO patent
applications by OECD countries in the five environmental domains. It shows that while water and
air pollution innovations have been increasing rapidly, the growth has been slower in the fields of
noise protection and environmental monitoring. Innovations related to waste disposal reached a
peak in 1991 and have declined since.
(Insert Figure 1 about here.)
Figure 2 gives patent counts in environmental technology for selected countries which have
exhibited significant levels of innovation. Germany has the highest number of patents, but relative
to the US and Japan, this partly reflects the „home bias‟ in EPO applications. France and the UK
6 While Jaffe and Palmer (1996) used patent totals (environmental and non-environmental patents) to study
the effect of environmental regulation on innovation, Lanjouw and Mody (1995) and Brunnermeier and
Cohen (2003) focus on environmental patents only, and their approach is thus similar to ours. However,
details on the selection of patent classes they used are not provided. 7 Following the discussion above, the search strategy includes not only „environmental‟ patent classes
covering end-of-pipe innovations, but also more general patent classes covering innovations related to
changes in production processes. In the absence of inclusion and exclusion keywords, the search algorithm
could overstate the former relatively to the latter.
7
both have at least 1000 patent applications over the period. These five countries represent between
74% and 84% of patent applications in each of the five domains. Germany alone, is responsible for
the highest number of filings in air, water, waste, and noise, while environmental monitoring is
dominated by the US and Japan.
(Insert Figure 2 about here.)
While Germany, Japan, the US, France and the UK are consistently important in
environmental technologies examined, other significant innovators in specific areas have included
Sweden (air), the Netherlands (water, monitoring), Italy (waste, noise) and Switzerland (noise)
(Table 1).
(Insert Table 1 about here.)
However, a comparison of the productivity of inventive activity across countries needs to
account for relative differences in the size of countries‟ scientific capacity.8 In Table 2, the counts
are weighted by country‟s gross domestic expenditure on R&D (GERD) to yield a measure of
patent intensity. On this basis, Germany as well as a number of smaller countries such as Austria,
Denmark, Switzerland, and Finland achieve the highest innovation output per dollar of R&D
expenditure.
(Insert Table 2 about here.)
2.2. Pollution abatement and control expenditures
Public policy may induce innovation by changing relative factor prices or introducing production
constraints. However, measurement of this effect is complicated because cross-country (or cross-
sectoral) data on regulatory stringency are rarely available or are not commensurable.
Consequently, various types of proxies have been used in the literature, including PACE measured
at the macroeconomic (e.g., Lanjouw and Mody 1996) or sectoral level (e.g., Brunnermeier and
Cohen 2003), the frequency of inspection visits (e.g., Jaffe and Palmer 1997), or various types of
derived measures (e.g., Johnstone et al. 2007).
8 For example, Madsen (2007) used the ratio of patents and real R&D expenditures as an indicator of
countries‟ research productivity.
8
The use of PACE data is very common in the empirical literature because it is one of the
few sources of quantitative information on environmental “compliance costs”. PACE includes
spending on PAC activities that are defined as “purposeful activities aimed directly at the
prevention, reduction and elimination of pollution or nuisances arising as a residual of production
processes or the consumption of goods and services” (OECD 2007c).9 This definition excludes
expenditure on natural resource management and risk prevention (such as prevention of natural
disasters and hazards), on nature protection (such as the protection of endangered species, the
establishment of natural parks and green belts), and on the exploitation and mobilisation of natural
resources (such as the supply of drinking water). Also excluded is expenditure that may primarily
satisfy health and safety requirements (such as expenditure intended for workplace protection) or
expenditure on the improvement of the production process for commercial or technical reasons,
even when they have environmental benefits (OECD 2007c).
However, PACE is only an imperfect measure of regulatory stringency. Several reasons
have been identified in the literature, including (a) the difficulty of identifying expenditures on
environmental compliance compared to what they would have been in the absence of
environmental regulations. The difficulty of establishing an appropriate baseline arises because
even in the absence of government regulation firms may still invest in such projects in order to
limit their potential exposure to liability and improve their environmental image with customers
(Jaffe et al. 1995); (b) Next, there is an important distinction between end-of-pipe solutions and
production process innovations, suggesting that it may be difficult for respondents to assign
expenditures to the latter. Specifically, firms may be unable to distinguish between the different
investment motives associated with adoption of integrated technologies. For example, what
proportion of expenditure on a new production process that increases material efficiency (and thus
reduces input costs) should be assigned to PAC? (see e.g., Lanjouw and Mody 1996); (c) Further,
firms could have an incentive to “strategically” overstate their PAC expenditures in order to
9 In this paper, consistent with this definition, the PACE data include only expenditure that is incurred
directly for PAC purposes (e.g., as a consequence of government environmental policies). Expenditure that
has positive environmental effects without being directly motivated by environmental concerns (e.g., energy
efficiency) is not included here. For the complete definition see Annex 2.
9
encourage regulators to weaken the degree of regulatory stringency, a common concern with
survey data; (d) Another concern associated with the use of aggregate measures of PACE to proxy
for stringency relates to cross-country differences in industrial composition. Countries with a lot of
polluting industry will have relatively high environmental compliance costs, regardless of the
stringency of their regulations (Levinson 1999); (e) Finally, despite significant efforts undertaken
to date, collection of PACE data is not fully harmonized across countries (OECD 2007c).
Despite these shortcomings, the PACE data is a rare source of information on the
opportunity costs created by countries‟ environmental policies and as such, if handled and
interpreted carefully, can be useful to study the effects of public environmental policies on
technological innovation. In particular, changes in opportunity costs due to increased regulatory
stringency, as proxied by higher PACE, are hypothesised to increase innovative behaviour targeted
at reducing environmental impacts of economic activity.
The PACE data used in this paper have been obtained from a series of annual surveys
published in OECD (2007c; 2003; 1996). The data are disaggregated into six environmental
domains -- including air, water, waste, land, noise, and monitoring (Table 3). In addition,
expenditures are disaggregated by the nature of the costs incurred, including (a) investment
expenditure, (b) internal current expenditure, and (c) transfer payments (such as subsidies and fees)
that are directly aimed at pollution abatement and control according to the abater principle (i.e.
sector where the PAC activity occurs) (OECD 2007c).10
Hence, PAC expenditure comprises actual
outlays and is thus conceptually different from PAC cost.
(Insert Table 3 about here.)
PACE is also disaggregated by the economic sector where the PAC activity occurs,
including the public sector, the business sector, and private and public specialised producers of
PAC services. Public PAC measures, which mainly concern waste and wastewater treatment, may
either be done directly by governments (central, regional, and local) and government agencies
10
Excluded are (a) calculated cost items (e.g. depreciation of fixed capital, cost of capital) as only actual
outlays are recorded, and (b) payments of interest, fines and penalties for non-compliance with environmental
regulations or compensations to third parties etc. as they are not directly linked with a PAC activity (OECD
2007c).
10
(further referred to as public sector) or be purchased as services from publicly-owned firms (further
referred to as public specialized producers). Private PAC measures, which mostly relate to
treatment or prevention of pollution to air and water and hazardous waste disposal from firm‟s own
operating activities, may either be done directly by the business sector or be purchased as services
from private specialized producers.11
Our dataset spans 30 countries for the period from 1985 to 2004. Three alternative PACE
variables are constructed representing PACE by the public sector including public specialized
producers (PACE_Public), PACE by the private sector (PACE_Private), and a dummy variable
(D_PrivateSP) with a unit value when data on private specialized producers is available and zero
otherwise.12
The PACE variables constructed and their interpretation are summarized in Table 4.
(Insert Table 4 about here.)
While there are a number of missing observations, Figures 3 and 4 provide time-series of
expenditures by the public and private sectors for selected countries in which the data is relatively
complete. In the case of public sector PACE Germany and Denmark appear to have relatively high
expenditures. For private sector PACE the two countries with the highest average percentages
(Czech Republic and Poland) have fallen recently.
(Insert Figures 3 and 4 about here.)
2.3. Other explanatory variables
In addition to regulatory stringency, which may induce innovation indirectly, governments often
encourage innovation directly through targeted R&D spending. Since PAC expenditures do not, by
definition, include expenditures on R&D, we use data on government budget appropriations and
outlays for R&D with the objective of control and care of the environment (GBAORD_Env). The
11
Specialized producers have grown in importance over the recent years as many of these activities have
increasingly been privatised or outsourced (e.g., municipal waste collection services, water and wastewater
treatment) (OECD 2007c). 12
Data on PACE by the public sector (PACE_Public) reported in OECD (2007c, 2003, 1996) include PACE
by public specialized producers. However, data on PACE by the business sector reported in OECD (2007c,
2003) do not, by construction, include PACE by private specialized producers (PACE_PrivateSP). This data
is available separately for some countries and some years. In order to avoid losing observations, and still be
able to isolate the “average” effect of private specialized producers, a new variable is constructed as a sum of
those two, PACE_Private = PACE_Business + PACE_PrivateSP, and a dummy variable (D_PrivateSP) is
created with a unit value when the data is available and zero otherwise. However, data on PACE by the
11
data are taken from the OECD Research and Development Statistics database (OECD 2007d) and
are normalized by GDP. The sign on this variable is expected to be positive.13
Aside from public policy, there are other important determinants of patenting activity for
environment-friendly technologies. Above all, the propensity of inventors from a particular country
to patent is likely to change over time, both because different strategies may be adopted to capture
the rents from innovation (e.g., Cohen et al. 2000) and because legal conditions may change
through time (e.g., Ginarte and Park 1997). In addition, inventors from non-European countries are
less likely to patent at the EPO (home country bias). For meaningful empirical analyses it is
therefore important to control statistically for these differences in the propensity to patent. As such
a variable was included reflecting total EPO patent applications (EPO_Total) filed across the
whole spectrum of technological areas (not only environmental). This variable thus serves both as a
„scale‟ and as a „trend‟ variable in that it controls for control for differences in the effects of the
size of an economy, its research capacity, etc. on innovation as well as changes in general
propensity to patent over time and across countries. The sign on this variable is expected to be
positive. Table 5 provides basic descriptive statistics for the dependent and explanatory variables.
(Insert Table 5 about here.)
3. Empirical model and results
An empirical model is developed in order to evaluate the effects of environmental policy and other
factors on patenting activity in selected areas of environmental technology. The following reduced-
form equation is specified:
tiititititi EPOGBAORDPACEEPATENTS ,,3,2,1, [1]
where i = 1,…,16 indexes country and t = 1985,…,2004 indexes year. The dependent variable is
measured by the number of patent applications in selected areas of environmental technology (air
pollution, water pollution, waste management, noise protection, and environmental monitoring).
private sector reported in OECD (1996) include also private specialized producers. Consequently, the dummy
variable equals unity for these observations.
12
The explanatory variables include a vector of proxies for regulatory stringency (PACEi,t),
government expenditures on environmental R&D (GBAORDi,t), and total EPO filings (EPOi,t).
Fixed effects ( i ) are introduced to capture unobservable country-specific heterogeneity. All the
residual variation is captured by the error term ( ,i t ). A negative binomial model is used to
estimate equation [1] (for details on count data models see e.g., Cameron and Trivedi 1998;
Maddala 1990; Hausman, Hall and Griliches 1984).
In the first model, a narrow definition of environmental technology is applied and a patent
count in technologies related to air pollution, water pollution and waste disposal is used as a
dependent variable. This is because these are the domains that are most affected by PAC
expenditures (OECD 2007c). Second, a broader definition of environmental technology is applied
and a patent count related to air pollution, water pollution, waste disposal, noise protection and
environmental monitoring is used as a dependent variable.
Alternative specifications are estimated for a pooled model and by including country fixed
effects. Applying a likelihood ratio test, we reject the null hypothesis that the fixed effects model
and the pooled model are equivalent. Hence, further discussion concerns only the results of the
fixed effects model. Table 6 (columns 1 and 2) gives estimated coefficients of the negative
binomial model using an unbalanced panel of 16 countries14
between 1985 and 2004.15
The
presence of missing observations and all-zero outcomes of patent count for some countries reduce
the size of the sample to 150 in the models estimated.
(Insert Table 6 about here.)
Differences in countries‟ scientific capacity and propensity to patent are mostly explained
by overall EPO patenting activity (EPO_Total), which is positive and statistically significant at the
1% level and higher in both models estimated.
13
Although these expenditures are also included in total R&D (GERD), the value of government expenditure
on environmental R&D is far too small to cause any problems of correlation. 14
Australia, Austria, Belgium, Canada, Finland, France, Germany, Italy, Japan, Korea, Netherlands,
Portugal, Slovakia, Sweden, United Kingdom, United States. 15
No PACE data is available for 1986.
13
Next we focus on variables which explain the direction of patenting. The estimated
coefficient of PACE by the private sector has a positive sign and is statistically significant at the
1% level and higher in both models estimated. The additional average effect of PACE by private
specialised producers is negative but insignificant. These results indicate that the cost-reduction
pressures in the private sector are effective in inducing inventive activity (and that the private
sector protects them through patenting).
The estimated coefficient of public sector PACE is insignificant in both models estimated.
The hypothesis that PACE by the public sector leads to increased patenting activity cannot be
confirmed. Several factors may be at play, including (a) lower inventive activity in the public
sector since cost increases (e.g., due to environmental compliance) do not provide the right signals
to innovate.16
This is well-known as public agencies are not profit maximizers and often face soft
budget constraints; (b) lower propensity to patent of public agencies because of their lesser concern
with rent appropriation (even if they do innovate, they do not patent). The importance of this effect
could be tested by including a variable which reflects the different propensity to patent for specific
technologies by the private and public sectors. Unfortunately this data is not available.
When it comes to government environmental R&D (GBAORD_Env), the estimated
coefficients have a positive sign and are statistically significant at the 5% level, suggesting that
government-financed research is a significant determinant of innovations in PAC activities.
Our results can be compared directly with those of previous studies. While Jaffe and
Palmer (1997) found that PACE had no impact on patenting activity (negative and insignificant
coefficient), Brunnermeier and Cohen (2003) found a positive and significant (5%) effect of PACE
on patenting. However, and as noted above, they used different definitions of „environmental‟
patents. Moreover, neither of these studies distinguished PACE for the public and private sectors.
And most importantly, their sample only included the U.S., with disaggregation across sectors.
Finally, an alternative measure of environmental policy stringency, based upon responses
to a survey of Chief Executive Officers undertaken by the World Economic Forum (WEF 2001,
16
However, innovation occurs if the signal is explicit – such as in the case of public funds being explicitly
devoted to environmental R&D (the coefficient on GBAORD is positive and significant).
14
through 2006), is used to complement the analysis. The results (columns 3 and 4 in Table 6)
broadly confirm the previous findings. Although the variable (WEF_STRNG) only represents the
average levels during 2001-2006, due to little variation in the index over time, the empirical
estimates provide a strong indication that more stringent environmental policies tilt the direction of
innovation towards more environment-friendly technologies.
4. Conclusions
This paper examines the impact of public environmental policy, as reflected in pollution abatement
and control expenditures, on innovations in environment-related technology. It is the first study to
look at these issues using a panel of countries. A strong relationship is found between patenting in
environmental technologies and general propensity to patent, government expenditures on
environmental R&D, and private (but not public) PACE expenditures. This suggests that the
stringency of environmental policy may be an effective means of inducing innovation if it is
translated in PAC expenditures by the private sector. In the public sector, expenditures on PAC
activities do not have a significant effect on environmental patenting and, if technological
innovation is the goal, public resources should rather be spent directly on R&D. These results are
broadly confirmed with a subsequent analysis on a broader cross-section of countries, using an
alternative measure of environmental policy stringency.
One of the important limitations of this research is the relatively small sample size. The
primary constraint on increasing sample size arises from missing observations with respect to the
PACE variable. Moreover, the use of PACE data as a proxy for regulatory pressure is not entirely
satisfactory. In an attempt to address these limitations, an alternative measure of regulatory
stringency at the aggregate level, which is commensurable across countries, is used in this paper.
In order to overcome the shortcomings in this paper and previous research, further work in
this area might include the development and analysis of a panel dataset for a sub-sample of
countries in which regulatory stringency for a particular pollutant is commensurable across
countries. This might be feasible for pollutants where performance standards with similar points of
incidence are commonly applied.
15
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18
Table 1. Number of EPO patent applications (1978-2004 annual average)
Air Water Waste Noise Monitoring AWW ALL sum
Australia 2.23 6.08 5.03 3.41 3.10 20.59 25.02 297
Austria 5.43 8.41 6.68 6.23 2.48 35.49 43.56 525
Belgium 2.56 6.27 4.45 4.10 5.59 21.41 30.34 360
Canada 3.81 9.23 4.49 5.85 3.43 30.85 39.51 466
Czech Republic 1.29 1.67 1.64 1.33 0.67 3.29 3.39 22
Denmark 3.69 4.87 4.91 5.98 1.88 20.28 25.43 309
Finland 3.23 4.55 3.99 3.16 4.88 17.76 25.56 297
France 16.59 28.30 30.33 24.06 24.88 126.25 183.60 2225
Germany 92.00 86.17 81.37 73.50 38.39 448.51 581.10 7000
Greece 1.03 1.35 1.13 1.33 0.83 3.47 3.60 31
Hungary 1.07 1.93 2.27 1.33 0.70 4.67 5.15 52
Iceland 0.00 0.38 0.00 0.00 0.00 0.83 0.83 1
Ireland 0.84 1.80 1.00 1.22 1.25 3.48 4.19 34
Italy 7.69 9.91 12.18 10.19 5.33 49.80 65.16 769
Japan 69.87 39.62 42.45 33.58 44.06 283.88 378.73 4429
Korea 2.08 4.51 4.02 3.25 1.58 13.03 15.57 125
Luxembourg 1.33 0.67 0.50 1.33 1.00 2.22 2.74 18
Mexico 0.00 1.00 1.00 0.00 0.00 2.00 2.00 3
Netherlands 3.97 11.02 7.21 6.81 7.52 37.65 54.02 662
New Zealand 0.96 1.05 0.80 1.67 0.73 1.83 1.89 16
Norway 1.30 3.14 2.11 1.88 1.81 8.42 10.02 120
Poland 0.88 1.49 2.40 1.33 0.80 3.77 4.26 29
Portugal 1.00 1.05 1.00 1.50 1.00 1.91 2.13 12
Slovakia 0.00 0.90 1.00 1.00 0.00 1.63 1.85 8
Spain 1.35 3.34 2.74 4.29 2.17 9.22 11.66 130
Sweden 8.02 9.70 8.15 7.45 6.23 44.88 58.67 715
Switzerland 6.70 9.37 9.23 8.89 5.29 41.28 56.16 681
Turkey 1.00 1.00 0.00 2.00 0.00 2.00 2.50 6
UK 13.56 22.41 13.54 10.35 14.45 90.59 119.77 1453
US 52.21 80.12 51.85 49.58 72.13 332.12 474.80 5707
OECD Total 292.50 347.49 286.17 359.95 336.42 1642.60 2212.95 26504
Note: AWW = Air + Water + Waste; ALL = Air + Water + Waste + Noise + Monitoring
Care has been taken to avoid double-counting of patents which fall in multiple categories.
19
Table 2. Number of EPO patent applications per dollar of R&D expenditure (Gross Domestic
Expenditures on R&D, in billions of US dollars, using PPP and 2000 prices)
Air Water Waste Noise Monitoring AWW ALL
Australia 0.38 1.02 0.85 0.57 0.52 3.46 4.21
Austria 1.78 2.76 2.19 2.05 0.81 11.65 14.31
Belgium 0.62 1.52 1.08 0.99 1.35 5.19 7.35
Canada 0.32 0.79 0.38 0.50 0.29 2.63 3.37
Czech Republic 0.73 0.95 0.94 0.76 0.38 1.88 1.94
Denmark 1.64 2.16 2.18 2.65 0.83 8.98 11.27
Finland 1.19 1.67 1.47 1.16 1.80 6.53 9.39
France 0.57 0.97 1.04 0.82 0.85 4.32 6.28
Germany 2.19 2.05 1.94 1.75 0.91 10.69 13.84
Greece 1.34 1.76 1.47 1.74 1.09 4.53 4.70
Hungary 1.39 2.51 2.95 1.73 0.91 6.07 6.69
Iceland 0.00 3.39 0.00 0.00 0.00 7.52 7.52
Ireland 1.11 2.37 1.32 1.61 1.65 4.58 5.52
Italy 0.56 0.72 0.89 0.74 0.39 3.64 4.76
Japan 0.85 0.48 0.52 0.41 0.54 3.47 4.63
Korea 0.13 0.27 0.24 0.20 0.10 0.79 0.94
Luxembourg 3.39 1.71 1.27 3.39 2.54 5.65 6.97
Mexico 0.00 0.33 0.33 0.00 0.00 0.65 0.65
Netherlands 0.58 1.61 1.05 0.99 1.10 5.49 7.88
New Zealand 1.33 1.46 1.11 2.31 1.01 2.54 2.62
Norway 0.68 1.64 1.10 0.98 0.94 4.40 5.23
Poland 0.38 0.64 1.03 0.57 0.34 1.62 1.84
Portugal 1.16 1.22 1.16 1.74 1.16 2.22 2.47
Slovakia 0.00 1.80 1.99 1.99 0.00 3.25 3.69
Spain 0.25 0.62 0.51 0.80 0.40 1.71 2.16
Sweden 1.19 1.44 1.21 1.11 0.93 6.69 8.74
Switzerland 1.35 1.89 1.86 1.79 1.07 8.32 11.32
Turkey 0.45 0.45 0.00 0.90 0.00 0.90 1.12
UK 0.54 0.89 0.54 0.41 0.57 3.58 4.74
US 0.26 0.40 0.26 0.25 0.36 1.65 2.36
Note: AWW = Air + Water + Waste; ALL = Air + Water + Waste + Noise + Monitoring
Care has been taken to avoid double-counting of patents which fall in multiple categories.
20
Table 3. Environmental domains related to PAC activities
En
vir
on
men
tal
mgm
t
En
vir
on
men
tal
pro
tect
ion
Po
lluti
on
abat
emen
t an
d
con
tro
l (P
AC
)
1. Protection of ambient air and climate
2. Wastewater management
3. Waste management
4. Protection and remediation of soil,
groundwater and surface water
5. Noise and vibration abatement
6. Protection against radiation
7. Protection of biodiversity and landscape
8. Research & Development
9. Other environmental protection activities
Nat
ura
l
reso
urc
e
mgm
t
Source: Adapted from OECD (2007: 9-18). For further details see CEPA (2000).
Table 4. PACE variables and their interpretation
Coefficient on variable Interpretation
PACEPublic
Effect of PACE by the public sector (incl. public SP)
PACEPrivate
Effect of PACE by the private sector (incl. private SP)
PACEPrivate
* DPrivateSP
Additional average effect of PACE by private specialized
producers, for the subsample of countries where such data
is available.
Table 5. Descriptive statistics for the sample of 16 countries
Variable Unit Obs Mean Std. dev. Min Max
PATENTS_AWW count 648 31.28 60.98 0 287
PATENTS_ALL count 648 40.50 78.37 0 375
PACE_Public % GDP 302 0.60 0.38 0.10 4.00
PACE_Private % GDP 206 0.59 0.37 0.00 2.50
D_PrivateSP binary 206 0.05 0.21 0 1
GBAORD_env_n % GDP 417 0.0153 0.0095 0.0004 0.0471
EPO_Total count (thousands) 948 1.7105 4.3878 0.0002 30.9420
Note: PATENTS_AWW includes counts for air pollution, water pollution, and waste disposal
PATENTS_ALL includes counts for air pollution, water pollution, waste disposal, noise
protection, and environmental monitoring.
21
Table 6. Regression estimates of NB models with country fixed effects
Dependent variable: Air pollution;
Water pollution;
Waste disposal
Air pollution,
Water pollution,
Waste disposal,
Noise protection;
Environmental
monitoring
Air pollution;
Water pollution;
Waste disposal
Air pollution,
Water pollution,
Waste disposal,
Noise protection;
Environmental
monitoring
(1) (2) (3) (4)
PACE_Public -0.058 0.011
(0.123) (0.111)
PACE_Private 0.364***
0.325***
(0.112) (0.100)
PACE_Private -0.100 -0.046
× D_PrivateSP (0.069) (0.062)
WEF_STRNG_avg
0.648***
0.601***
(0.129) (0.124)
GBAORD_env_n 10.025**
8.187**
20.824***
19.662***
(4.377) (3.940) (3.127) (3.059)
EPO_totals 0.018***
0.023***
0.023***
0.026***
(0.003) (0.003) (0.002) (0.002)
Intercept 3.096***
3.188***
-2.597***
-2.329***
(0.243) (0.241) (0.743) (0.714)
Observations 150 150 626 626
Groups 16 16 33 33
Log-likelihood -471.47 -497.91 -1821.38 -1946.26
Wald chi2 63.90 116.47 235.46 290.93
(Prob > chi2) (0.000) (0.000) (0.000) (0.000)
Notes:
*,
** and
*** refer to 10%, 5% and 1% level of statistical significance. Standard errors are in
parentheses. The dependent variable is the count of patent applications in a given technological area. When
fixed effects are included, the intercept represents the average value of the country-specific fixed effects.
22
Figure 1. Number of EPO Patent Applications in Selected Areas of Environmental
Technology
Figure 2. Number of EPO Patent Applications in Environmental Technology, by Inventor
Country
23
Figure 3. PACE expenditures by the public sector (incl. public SP) in selected countries
Figure 4. PACE expenditures by the business sector and private specialised producers in
selected countries
24
Annex 1. Patent classes and keywords for selected areas of environmental technology
AIR POLLUTION IPC class Keywords
Separating dispersed particles from gases or vapour , e.g. air, by
electrostatic effect B03C 3/00
(exhaust, effluent,
flue, combustion,
waste) AND (gas,
gases, smoke, air)
Processes for making harmful chemical substances harmless, or less
harmful, by effecting a chemical change in the substances A62D 3/00
Separating dispersed particles from gases or vapours by gravity, inertia,
or centrifugal forces B01D 45/00
Filters or filtering processes specially modified for separating dispersed
particles from gases or vapours B01D 46/00
Separating dispersed particles from gases, air or vapours by liquid as
separating agent B01D 47/00
Separating dispersed particles from gases, air or vapours by other
methods B01D 49/00
Combinations of devices for separating particles from gases or vapours B01D 50/00
Auxiliary pre-treatment of gases or vapours to be cleaned B01D 51/00
Chemical or biological purification of waste gases, e.g. engine exhaust
gases, smoke, fumes, flue gases, aerosols B01D 53/00
Chemical or biological purification of waste gases B01D 53/34-36
Dust extraction equipment on grinding or polishing machines B24B 55/06-10
Details of, or accessories for, apparatus for shaping the material;
Exhausting or laying dust B28B 17/04
Accessories specially adapted for for removing or laying dust, e.g. by
spraying liquids; for cooling work B28D 7/02
Details of, or accessories for, portable power-driven percussive tools;
Removing or laying dust by liquid or by exhausting dust-loaded air B25D 17/14-18
Auxiliary measures taken, or devices used, in connection with loading
or unloading; Preventing escape of dust B65G 69/18
Materials not provided for elsewhere; for dust-laying or dust-
absorbing C09K 3/22
Use of additives to fuels or fires for particular purposes for reducing
smoke development C10L 10/02
Arrangements for confining or removing dust, fly, or the like D01H 11/00
Blast furnaces; Dust arresters C21B 7/22
Manufacture of steel; Removal of waste gases or dust; Offtakes or
separating apparatus for converter waste gases or dust C21C 5/38-40
Means or methods for preventing, binding, depositing, or removing
dust; Preventing explosions or fires E21F 5/00
Exhaust or silencing apparatus for rendering innocuous by thermal or
catalytic conversion of noxious components of exhaust F01N 3/08-38
Apparatus for treating combustion-air, fuel, or fuel-air mixture, by
catalysts F02M 27/02
Combustion apparatus with arrangements for burning uncombusted
material from primary combustion F23B 5/00
Combustion apparatus characterised by arrangements for returning
combustion products or flue gases to the combustion chamber for
completing combustion
F23C 9/06
Shaft or like vertical or substantially vertical furnaces; Arrangements of
dust collectors F27B 1/18
Electrical control of exhaust gas treating apparatus F01N 9/00
25
WATER POLLUTION IPC class Keywords
Accommodation for crew or passengers; Soil-water discharges B63B 29/16
Barges or lighters for collecting pollution from open water B63B 35/32
Arrangements of installations for treating waste-water or sewage B63J 4/00
Materials for treating liquid pollutants, e.g. oil, gasoline, fat C09K 3/32
Treatment of water, waste water, or sewage C02F 1/00
Biological treatment of water, waste water, or sewage C02F 3/00
Aeration of stretches of water C02F 7/00
Multistep treatment of water, waste water or sewage C02F 9/00
Devices for treatment of sludge C02F 11/00
Apparatus for cleaning or keeping clear the surface of open water E02B 15/00
(NOT 15/02)
Methods or installations for obtaining or collecting drinking water or
tap water E03B 3/00
WASTE DISPOSAL IPC class Keywords
Processes for making harmful chemical substances harmless, or less
harmful, by effecting a chemical change in the substances A62D 3/00
( exhaust, effluent,
flue, combustion,
waste) AND (gas,
gases, smoke, air)
Treatment of water, waste water, sewage, or sludge
C02F
(exhaust, effluent,
flue, combustion)
AND (gas, gases,
smoke, air) Chemical or biological purification of waste gases
B01D 53/34-
36
Disposal of solid waste B09B
Cremation furnaces; Consuming waste by combustion F23G
Treating radioactively contaminated material; Decontamination
arrangements therefor G21F 9/00
NOISE PROTECTION IPC class Keywords
Details of, or accessories for, portable power-driven percussive tools;
Arrangements of noise damping means of exhaust silencers B25D 17/11-12
Arrangements for absorbing or reflecting air transmitted noise from
road or railway traffic E01F 8/00
Sanitary or other accessories for lavatories; Noise-reducing means
combined with flushing valves E03D 9/14
Constructions and structures; Noise or sound insulation, absorption, or
reflection E04B 1/82-90
Flooring; Separately-laid insulating layers; Other additional insulating
measures; Floating floors for sound insulation E04F 15/20
Doors, windows, or like closures for special purposes; Border
constructions for insulation against noise E06B 5/20
Silencing apparatus characterised by method of silencing F01N 1/00
Exhaust or silencing apparatus, or parts thereof having two or more
separate silencers in series or in parallel F01N 7/02-04
Silencers specially adapted for steam engines F01B 31/16
Acoustic insulation F02B 77/13
Air intakes for gas-turbine plants or jet-propulsion plants having
provisions for noise suppression F02C 7/045
Intake silencers, combined air cleaners and silencers specially adapted
for, or arranged on, internal-combustion F02M 35/12-14
Devices or appurtenances for use in, or in connection with, pipes or
pipe systems; Noise absorbers F16L 55/033
26
Silencing means for blasting operations F42D 5/055
Methods or devices for protecting against, or damping of, acoustic
waves, e.g. sound G10K 11/16
Insulating elements for vehicles, e.g. for sound insulation B60R 13/08
sound, noise
Ground or aircraft-carrier-deck installations for reducing engine or jet
noise; Protecting airports from jet erosion B64F 1/26
Protection of permanent way against development of dust or against the
effect of wind, sun, frost, or corrosion; Means to reduce development of
noise
E01B 19/00
Design or layout of roads, e.g. for noise abatement, for gas absorption E01C 1/00
Plants characterised by the form or arrangement of the jet pipe or
nozzle; F02K 1/
.. using fluid jets to influence the jet flow for attenuating noise .. 1/34
.. nozzles having means, e.g. a shield, reducing sound radiation in a
specified direction .. 1/44
.. nozzles having means for adding air to the jet or for augmenting the
mixing region between the jet and the ambient air, e.g. for silencing .. 1/46
Detonation-wave absorbing or damping means; Blasting mats F42D 5/05
Filtering, cooling, or silencing cooling-air F01P 11/12
Air intakes for gas-turbine plants or jet-propulsion plants F02C 7/04
Heat or noise insulation F02C 7/24
Means in valves for absorbing fluid energy for preventing water-
hammer or noise F16K 47/02
Devices or appurtenances for use in, or in connection with, pipes or
pipe systems; Energy absorbers; Noise absorbers F16L 55/02
NOT (F41,
G01, H01, H02,
H03, H04, H05)
(absorb, reduc,
abate, barrier,
prevent, deaden,
dampen, anti) AND
(sound, noise)
NOT (F01N) silencer
ENVIRONMENTAL MONITORING IPC class Keywords
Investigating or analysing materials by determining their chemical
or physical properties
G01N
((toxi, pollu, contaminat,
monitor) AND (water,
air, atmos, soil))
OR
((water, air, atmos, soil)
AND (effluent, flue,
exhaust, water))
OR
(environment AND
(water, air, atmos, soil))
OR
((water, air, atmos, soil)
AND (analys, measur))
Measurement of mechanical vibrations or ultrasonic, sonic, or
infrasonic waves
G01H
(NOT 1/00) noise
Investigating or analysing materials by specific methods: water G01N 33/18
Investigating or analysing materials by specific methods: Earth
materials G01N 33/24
Measuring X-radiation, gamma radiation, corpuscular radiation, or
cosmic radiation
G01T 1/00
(NOT 1/29-40)
Details of radiation-measuring instruments G01T 7/00
Note: Keyword searches were applied on titles of patent documents. All keywords were used with a wildcard.
27
Annex 2. Environmental domains related to PAC activities
1 Protection of ambient air and climate
1.1 Prevention of pollution through in-process modifications -- for the protection of ambient air;
for the protection of climate and ozone layer
1.2 Treatment of exhaust gases and ventilation air -- for the protection of ambient air; for the
protection of climate and ozone layer
1.3 Measurement, control, laboratories and the like
1.4 Other activities
2 Wastewater management
2.1 Prevention of pollution through in-process modifications
2.2 Sewerage networks
2.3 Wastewater treatment
2.4 Treatment of cooling water
2.5 Measurement, control, laboratories and the like
2.6 Other activities
3 Waste management
3.1 Prevention of pollution through in-process modifications
3.2 Collection and transport
3.3 Treatment and disposal of hazardous waste -- thermal treatment; landfill; other
3.4 Treatment and disposal of non-hazardous waste -- incineration; landfill; other
3.5 Measurement, control, laboratories and the like
3.6 Other activities
4 Protection and remediation of soil, groundwater and surface water
4.1 Prevention of pollutant infiltration
4.2 Cleaning up of soil and water bodies
4.3 Protection of soil from erosion and other physical degradation
4.4 Prevention and remediation of soil salinity
4.5 Measurement, control, laboratories and the like
4.6 Other activities
5 Noise and vibration abatement (excluding workplace protection)
5.1 Preventive in-process modifications at the source -- road and rail traffic; air traffic; industrial
and other noise
5.2 Construction of anti noise/vibration facilities -- Road and rail traffic; Air traffic; Industrial and
other noise
5.3 Measurement, control, laboratories and the like
5.4 Other activities
6 Protection against radiation (excluding external safety)
6.1 Protection of ambient media
6.2 Transport and treatment of high level radioactive waste
6.3 Measurement, control, laboratories and the like
6.4 Other activities
Source: Adapted from OECD (2007: 17-18). For further details see CEPA (2000).