Klimapolitik ohne Standortnachteile

In the absence of a broad international agreement, national climate policies are less efficient, due to carbon leakage, and more costly, due to causing unemployment and a loss of competitiveness on international markets. As, in many countries, a substantial fraction of emissions results from the production of intermediate goods, such as electricity or transportation services, we investigate whether the above negative side-effects can be addressed by a policy mix that (partially) contains the effects of climate policy to the intermediate goods sector. We use a four-sector general equilibrium model to study a policy mix that consists of taxing emissions and subsidizing the intermediate good. We show that such containment is a second-best approach to combat carbon leakage and to maintain a favorable international market position. Also, it can help to reduce climate-policy-induced unemployment.

Technological Diversity and Cost Uncertainty

In many industries, different technologies are used simultaneously for the production of a homogeneous good. Such diversification is socially beneficial, because it reduces the transmission of factor price volatility, like oil-price shocks, to consumer prices. Therefore, many countries have implemented policies aimed at increasing technological diversification. The question is whether such policies are necessary. We use a two-stage investment model to address this question in the setting of perfect competition and of a monopoly. We show that factor price uncertainty leads to diversification, if capital is not too expensive, and that this diversification is due to each firm investing in a diversified technology portfolio. An important implication of this form of diversification is that technological diversity is socially optimal, even in the case of a monopoly. Thus policy intervention is unnecessary and might even be detrimenta

Environmental Policy à la Carte: Letting Firms Choose their Regulation

Environmental policy often has to be devised under informational constraints, like uncertainty and asymmetric information. We consider an environmental policy that aims at reducing the welfare losses caused by asymmetric information while being sufficiently simple for implementation. In this policy, firms can choose between being regulated with an emission tax or a permit market. This serves as a screening device; the firms reveal private information by choosing an instrument. We show that such a menu of policy options improves upon conventional environmental policy. Furthermore, the optimal policy is simple and thus easily implementable. The approach is also theoretically interesting, because the simultaneous use of price- and quantity-based instruments induces an asymmetry into the pricesversus- quantities decision compared to Weitzman’s criterion. Especially, there can be an optimal pooling equilibrium where all firms choose the tax, but it is never optimal that all firms participate in permit trading.Environmental Policy, Asymmetric Information, Screening, Uncertainty, Prices-versus-Quantities

Adaptation to catastrophic events with two layers uncertainty: Central planner perspective

We study the optimal adaptation to extreme climate events by the central gov- ernment in a setup where events are dynamically uncertain and the government does not know the true probabilities of events. We analyze dierent policy decision rules minimizing expected welfare losses for sites with dierent expected damages from the catastrophic event. We nd out under which conditions it is optimal to wait before implementation of a prevention measures to obtain more information about the underlying probabilistic process. This waiting time crucially depends on the information set of the planner and the implemented learning procedure. We study dierent learning procedures on behalf of the planner ranging from simple perfect learning to two-layers Bayesian updating in the form of Dirichlet mixture processes

Temporary and permanent technology lock-ins in the quality-differentiated Bertrand competition

We consider a setting where strategic behavior of r&d firms can lead to different types of a technology lock-in, permanent or temporary, in an eventually inferior technology. The simple setting with one incumbent and one potential entrant may lead to a wide variety of possible strategic regimes. We study conditions on relative market strength of the incumbent and the entrant which lead to different strategic actions and demonstrate, that such a strategic behavior is not always socially suboptimal, since it may lead to faster development of the existing technology due to persistent threat of the potential entrant. We further elaborate on the selection of support tools which may induce the development of new technology in the second-best world and establish criteria for these tools to be social welfare improving ones

Optimal Mix of Policy Instruments and Green Technology Transitions

Green innovation is a key element in fighting climate change. But there are several challenges that need to be addressed in managing a green technology transition, both in terms of interacting market failures (environmental externality, public good nature of innovation, strategic behaviour of incumbents protecting an emission-intensive technology) and as the structure of the technology market (whether the new technology is offered by a monopolistic incumbent or whether there is some competition induced by market entrants) will evolve throughout the transition. In this paper, we investigate the question what constitutes the optimal policy at different stages of the technology transition and for different market structures. We first analyse a policy mix that can implement a first-best outcome. We show that this mix will differ between different market settings and for different stages of the technology transition. Second, we investigate the choice between a push policy (subsidy for the new technology) and a pull strategy (tax on the old technology) and show that throughout the transition, the policy should be switched, often even more than once. Overall, our results indicate that managing a green technology transition requires a sequence of different policies attuned to the state of the transition and that this sequence differs substantially for different cases, for example, different levels of environmental damage or different cost advantages of the incumbent over entrants

Unilateral climate policy and optimal containment in an open economy

In the absence of a broad international agreement, national climate policies NEWLINE are less efficient, due to carbon leakage, and more costly, due to causing NEWLINE unemployment and a loss of competitiveness on international markets. As, NEWLINE in many countries, a substantial fraction of emissions results from the production NEWLINE of intermediate goods, such as electricity or transportation services, NEWLINE we investigate whether the above negative side-effects can be addressed by NEWLINE a policy mix that (partially) contains the effects of climate policy to the intermediate NEWLINE goods sector. We use a four-sector general equilibrium model to NEWLINE study a policy mix that consists of taxing emissions and subsidizing the intermediate NEWLINE good. We show that such containment is a second-best approach NEWLINE to combat carbon leakage and to maintain a favorable international market NEWLINE position. Also, it can help to reduce climate-policy-induced unemployment

Environmental Policy à la Carte: Letting Firms Choose their Regulation

Environmental policy often has to be devised under informational constraints, like uncertainty and asymmetric information. We consider an environmental policy that aims at reducing the welfare losses caused by asymmetric information while being sufficiently simple for implementation. In this policy, firms can choose between being regulated with an emission tax or a permit market. This serves as a screening device; the firms reveal private information by choosing an instrument. We show that such a menu of policy options improves upon conventional environmental policy. Furthermore, the optimal policy is simple and thus easily implementable. The approach is also theoretically interesting, because the simultaneous use of price- and quantity-based instruments induces an asymmetry into the pricesversus-quantities decision compared to Weitzman’s criterion. Especially, there can be an optimal pooling equilibrium where all firms choose the tax, but it is never optimal that all firms participate in permit trading

Dynamic heterogeneous R&D with cross-technologies interactions

In many countries, inducing large-scale technological changes has become an important policy objective, as in the context of climate policy or energy transitions. Such large-scale changes require the development of strongly interlinked technologies. But current economic models have little flexibility for describing such linkages. We present a model of induced technological change that covers a fairly large set of cross-technology interactions and that can describe a wide variety of long-run developments. Using this model, we analyse and compare the development induced by optimal fifrm behaviour and the socially optimal dynamics. We show that the structure of cross-technology interactions is highly important. It shapes the dynamics of technological change in the decentralised and the socially optimal solution, including the prospects of continued productivity growth. It determines whether the decentralised and the socially optimal solution have similar or qualitatively difffferent dynamics. Finally, it is highly important for the question whether simple r&d policies can induce effifficient technological change