Signatories of the Paris Agreement under the United Nations Framework Convention on Climate Change (UNFCCC) are exploring avenues to drastically abate their greenhouse gases (GHG) emissions. This demands a rapid transition to low-carbon energy systems. However, some regions may be tempted to exploit new hydrocarbon deposits due to energy security concerns or because of oil companies seeking additional profits. This paper proposes prospective energy scenarios for the Province of Quebec up to 2050 under GHG emission reduction constraints with and without new hydrocarbon exploitation. The main objective is to measure impacts of developing new hydrocarbon projects on achieving stringent GHG reduction objectives (up to -80%). Our analysis relies on the North American TIMES Energy Model (NATEM) that belongs to the MARKAL/TIMES family of models supported by the International Energy Agency. In terms of hydrocarbon exploitation, a recent project proposed by the oil industry for exploiting deposits in the Anticosti Island. In our GHG abatement scenarios, results indicate that the hydrocarbons of Anticosti Island would be exported and have virtually no effect on the energy consumption mix in Quebec. However, 2050 GHG emission levels would increase by nearly 7% in the reference case (baseline). Greater total GHG reductions would thus be required from the baseline at a significantly higher marginal abatement cost.