Nonetheless, given the timeframes involved in constructing nuclear power plants (there is no planning yet) and the difficulties in setting up large-scale hydroelectric plants in Mexico, nearly all of the investment needed to reach this level will come from non-conventional renewable energy sources. This provides the opportunity to consume electricity generated with renewable sources, for which a higher price is normally paid. Worldwide there are over 6 million customers with these systems, of whom 2.6 million are in Germany.