Journées de l'optimisation 2007 Optimizations days

This paper is aimed at exploring the optimal timing of global environmental policies in a context of uncertainty concerning the sensitivity of climate to an increase of GHG concentration and the access to efficient carbon free technologies. Using a simplified integrated assessment model, we formulate a stochastic control problem which admits as solution a policy satisfying a precautionary principle and optimizing a global welfare criterion. Two sources of uncertainty are modeled: (i) the climate sensitivity which determines the long term goal of atmospheric carbon concentration, and (ii) the availability of carbon-free technologies.

We describe a model of Nash-Cournot competition among several generating companies, with Time of Use (TOU) pricing. The TOU pricing feature makes the model mathematically similar to a multicommodity model, with own and cross price elasticities of demand for electricity at different times of day. In addition, we include an elasticity for lagged demand, i.e., a kind of "inertia" in that demand in a month depends in part on demand in the previous month, in addition to the dependence on the current month's prices. These complications create challenges to formulate the model, and to solve it. We present variational inequality and complementarity formulations, with and without the representation of the effects of a transmission network on pricing. We present some computational results for illustration.

Power produced in Québec is 95% hydro. This concentration means that the province's power reserves depend heavily on water reserves. Given this potential vulnerability and the recent trend towards wind power, it has been suggested that a greater stability of power reserves could result from some diversification of the power sources. Our goal is to quantify the complementarity relationship between hydro and wind power. We statistically model both wind and water inflows on a yearly basis, and identify an appropriate copula to link them. A quantile approach is then used to evaluate the potential benefits of a wind-diversified power system.

Suite à des études techniques et des simulations de différents scénarios d’intégration de leurs réseaux de transports, plusieurs pays d’Afrique de l’ouest ont récemment reçu d’importants prêts d’institutions internationales pour construire des réseaux internationaux et créer un «power pool» pour optimiser la production d’électricité. Des questions se posent néanmoins quant à la capacité institutionnelle de ces pays à gérer un secteur de l’électricité international et intégré. Cette présentation expose la justification des investissements visant l’intégration des réseaux d’électricité d’Afrique de l’ouest ainsi que les obstacles auxquels elle fait face.