Scientists at the U.S. Department of Energy’s Argonne National Laboratory have prepared a model to assess which types of power plants are likely to generate the electricity used by PHEVs in different regions of the United States. The model was arranged to study the impact of different fuel sources for plug in vehicles on the environment. The study has brought some interesting facts to light that could help save energy. These for example include charging plug in hybrids overnight when electricity is available at cheapest rate or even charging the hybrid in the middle of the day. This would change the energy source ranging from coal generated power to renewable energy sources subsequently resulting in varying economic and environmental effects of owning a plug-in hybrid.