The solar greenhouse project is aimed at the development of a greenhouse concept for the Netherlands with zero-fossil energy consumption. The solar greenhouse is formulated as a combination of a low energy demand greenhouse, an energy recovery installation and an energy storage facility. In this paper, energy saving options such as new building materials, a dehumidifier, a heat pump and long term storage are studied. A simplified model is being developed in MATLAB to describe the total system. First calculations indicate that implementing the properties of the new building materials with high insulation, the installation of a dehumidifier, a heat pump and a storage system provides a significant reduction of the fossil energy use and an increase in the relative solar energy contribution to the total energy use.