Road construction operations often require considerable amounts of energy in the form of fossil fuels, thus generating considerable greenhouse gas (GHG) emissions. While fuel efficiency of the heavy construction equipment is extensively studied, limited attention is given to how the construction process can be planned in order to reduce energy use and GHG-emissions. In this paper a conceptual model is proposed for the assessment of energy use and GHG-emission in road construction projects. When applied to a case study the conceptual energy model is a useful tool to asses and evaluate project alternatives in the early planning stages of road construction projects. As a result both the energy use and GHG-emissions in road construction projects can be reduced.