Nikolaj Moretti

Nikolaj Moretti

PhD candidate at PIK Potsdam and the University of Potsdam

Research

Publications

Rechtfertigt Klimapolitik eine Erhöhung der Verschuldung? Eine grün-goldene Regel für die Klimapolitik

Edenhofer, O., Eydam, U., Heinemann, M., Kalkuhl, M., Moretti, N., published in Perspektiven der Wirtschaftspolitik (in Kürze), 2025

Dieser Artikel präsentiert eine Komponente einer modifizierten Investitionsregel für die Klimapolitik, die in Anlehnung an die goldene Regel der Finanzwissenschaft als „grün-goldene Regel“ bezeichnet wird. Die Höhe der Neuverschuldung von den vermiedenen Klimaschäden abhängig gemacht. Wir zeigen beispielhaft, dass bei Grenzschäden (Social Costs of Carbon) von 200 Euro pro Tonne eine zusätzliche Neuverschuldung von insgesamt 161 Milliarden Euro bis 2030 möglich wird, sofern die Emissionsziele des Klimaschutzgesetzes 2020-2030 erreicht werden.

Interaction effects between dynamic hybrid products and traditional deferred annuities in the German life insurance market

Moretti, N., Bartels, J., published in Financial Markets and Portfolio Management, 2021

In this paper, we study interaction effects between dynamic hybrid products and traditional deferred annuity contracts that are sold by the same insurance company. We build a model including a detailed representation of the profit participation mechanism and analyse it using a Monte Carlo simulation.

Working Papers

A Green-Golden Rule for Climate Policy

Edenhofer, O.; Eydam, U.; Heinemann, M.; Kalkuhl, M.; Moretti, N., published in ‘SSRN’, 2025

We elaborate a fiscal rule that conditions the admissible deficit for a government on the observed reduction in carbon emissions based on a welfare economic framework. We call this adaptation of the classical “golden rule of public finance” to the climate context “green-golden rule”. The conceptualization of climate-investment as reduction in carbon emissions has a key advantage: Carbon emissions are measurable in t/CO2 and homogeneous with returns given by the Social Cost of Carbon. This makes it possible to overcome the major criticisms to the golden rule, namely the difficulty to assess the returns on public investment and the vagueness of the definition of invesmtent and the connected “creative accounting critique”. We quantify a quantity version and a price version of the rule for the case of Germany.

Trading deficits for investment: Optimal deficit rules for present-biased governments

Bergmann, T. Moretti, N., published in CEPA Discussion Paper, 2025

In this paper, we characterize the optimal deficit-rule for a present-biased government, accounting for the distortion of long-term investment it induces. We analyze the effect of a shock to the productivity of investment on the optimal deficit-cap. Furthermore, we compare the welfare outcome of a balanced budget rule, the absence of any deficit rule, and a benchmark deficit rule.

Fiscal Policy and Energy Price Shocks

Blanz, A., Eydam, U., Heinemann, M., Kalkuhl, M., Moretti, N., published in CEPA Discussion Paper, 2023

In this paper, we analyse the effect of different fiscal policy measures in response to a non-anticipated energy price shock in a real-business-cycle model with heterogeneous households differing ith respect to their energy consumption and savings capacity.

Work in Progress

Overcoming the Climate Policy Dilemma: The Role of Debt and Redistribution under Intergenerational Borrowing Constraints

Ongoing

We investigate the effect of (intergenerational) borrowing constraints on climate policy in a simple political economy model where households differ in income. Binding borrowing constraints increase implicit discount rates. We analyze how intra- and intergenerational transfers can increase support for climate policy. (With Matthias Kalkuhl and Maximilian Kellner)