WELFARE MEASUREMENT UNDER THREATS OF ENVIRONMENTAL CATASTROPHES

Welfare measures under threats of environmental catastrophes are studied using the "parable" apparatus of Weitzman and Lofgren [22]. The occurrence probability of the catastrophic event is driven (at least partly) by anthropogenic activities such as natural resource exploitation. Without external effects, the green NNP is a genuine welfare measure vis-à-vis a particular parable economy. Often, however, the occurrence hazard constitutes a public bad, treated as an externality by agents who ignore their own contribution to its accumulation. In such cases the green NNP, although accounting for the event hazard rate per se, fails to properly internalize future effects on the hazard rate of current economic activities and as a result overestimates welfare. The bias term associated with the green NNP is derived and expressed in a simply and interpretable form.green NNP, environmental catastrophes, hazard rate, uncertainty, Environmental Economics and Policy,

On the Dynamics of Competing Energy Sources

We characterize the dynamics of energy markets in which energy is derived from polluting (fossil) and clean (solar) resources. The analysis is based on geometric optimal control considerations. An important feature of solar energy technologies is that their cost of supply is predominantly due to upfront investment in capital infrastructure (rather than to actual supply rate) and this feature has important implications for the market allocation outcome. In particular, it gives rise to a threshold behavior in that solar energy is adopted only when the price of fossil energy exceeds a certain threshold. Under this condition solar technologies will (eventually) dominate energy supply by driving fossil energy altogether out of the energy sector. A tax on fossil energy can have a substantial impact since it changes the threshold price. A quantity restriction (e.g., a cap on fossil energy) allows for the coexistence of clean and polluting energy technologies also in the long run, and its effect on the use of fossil energy is more moderate.fossil and solar energy, characteristic curves, price thresholds, environmental regulation, Environmental Economics and Policy, Research and Development/Tech Change/Emerging Technologies, Research Methods/ Statistical Methods, Resource /Energy Economics and Policy,

ENDANGERED AQUIFERS: GROUNDWATER MANAGEMENT UNDER THREATS OF CATASTROPHIC EVENTS

Resource /Energy Economics and Policy,

ITERATIVE LEAST SQUARES ESTIMATION OF CENSORED REGRESSION MODELS WITH UNKNOWN ERROR DISTRIBUTIONS

Research Methods/ Statistical Methods,

KNOWLEDGE SPILLOVER, LEARNING INCENTIVES AND ECONOMIC GROWTH

Knowledge spillover implies that the social value of knowledge is higher than its private value and leads to insufficient private investment in human capital. This paper examines implications for economic growth and offers a remedy. An incentive mechanism that implements the socially optimal outcome is offered based on learning subsidy and flat income or consumption taxes (each levied at a different phase of the growth process). The scheme is self-financed in that the tax proceeds cover exactly the subsidy payments at each point of time.endogenous growth, human capital, knowledge spillover, learning incentives, linear taxes, International Development, C61, H21, O33, O38, O41,

RESOURCE EXPLOITATION, BIODIVERSITY LOSS AND ECOLOGICAL EVENTS

We study the management of a natural resource that supports ecosystems as well as human needs. The reduction in the resource base introduces a threat of occurrence of catastrophic ecological events, such as the sudden collapse of the national habitat that lead to severe loss of biodiversity. The event occurrence conditions involve uncertainty of various types, and the distinction among these types affects the optimal exploitation policies. When uncertainty is due to our ignorance of some aspects of the underlying ecology, the isolated equilibrium states characterizing optimal exploitation for many renewable resource problems become equilibrium intervals. Events triggered by genuinely stochastic environmental conditions maintain the structure of isolated equilibria, but the presence of event uncertainty shifts these equilibrium states relative to their position when occurrence conditions are known with certainty.ecosystem, resource management, event uncertainty, biodiversity, extinction, Resource /Energy Economics and Policy,

STOCHASTIC ENERGY DEMAND AND THE STABILIZATION VALUE OF ENERGY STORAGE

The economic value of energy storage to meet peak electricity demand is analyzed with an emphasis on the role of demand uncertainty. The concept of the stabilization value, which measures that part of the benefit of the storage project which is due solely to the stochastic demand components, is defined. The magnitude of the stabilization value, relative to the overall value of energy storage, is evaluated in terms of a simple model that accounts for the relevant characteristics of the electric power utility's production mix. It is found that neglecting the demand uncertainty can seriously bias the benefit assessment of the storage project as well as the determination of the optimal storage capacity.Resource /Energy Economics and Policy,

Endangered Species and Natural Resource Exploitation: Extinction vs. Coexistence

The threat on the survival of animal species due to intensive use of natural resources is incorporated within resource management models, paying special attention to uncertainty regarding the conditions that lead to extinction. The manner in which the potential benefits forgone due to the species extinction (denoted extinction penalty) induce more conservative exploitation policies is studied in detail. When the extinction penalty is ignored, the optimal policy is to drive the resource stock to a particular equilibrium level from any initial state. When the extinction penalty is considered and the conditions that lead to extinction are not fully understood (i.e., involve uncertainty), an interval of equilibrium states is identified, which depends on the penalty and the immediate extinction risk.Resource /Energy Economics and Policy,

Endogenous Discounting and Climate Policy

Under risk of abrupt climate change, the occurrence hazard is added to the social discount rate. As a result, the social discount rate (i) increases and (ii) turns endogenous to the global warming policy. The second effect bears profound policy implications that are magnified by economic growth. In particular, we find that greenhouse gases (GHG) emission should be terminated at a finite time so that the ensuing occurrence risk will vanish in the long run. Due to the public bad nature of the catastrophic risk, the second effect is ignored in a competitive allocation and unregulated economic growth will give rise to excessive emissions. In fact, the GHG emission paths under the optimal and competitive growth regimes lie at the extreme ends of the range of feasible emissions. We derive the Pigouvian hazard tax that implements the optimal growth regime.abrupt climate change, hazard rate, discounting, economic growth, emission policy, H23, H41, O13, O40, Q54, Q58,

UNCERTAINTY AND IRREVERSIBILITY IN GROUNDWATER RESOURCE MANAGEMENT

Optimal exploitation of renewable groundwater resources when extraction affects the probability of occurrence of an irreversible event is studied. The term irreversible signifies that the event occurrence renders the resource obsolete. It is found that uncertainty concerning the event occurrence has a profound effect. Under certainty - when the stock level below which the event occurs is known in advance - the optimal state process converges to a unique equilibrium state. Under uncertainty, when the event occurrence level is unknown, we identify equilibrium intervals and show that optimal processes initiated elsewhere converge to a boundary of one of these intervals. Inside an equilibrium interval, the expected loss due to the event occurrence is so high that it does not pay to extract in excess of recharge, even though under certainty doing so would be beneficial. These properties are illuminated by means of an example for which analytic solutions are derived.Resource /Energy Economics and Policy,