The construction of conventional scale geothermal power plants (50-150 MW) requires large number of wells and therefore high investment cost of drilling. Those initial phases of the development need to be completed and the availability of steam has to be confirmed, before the decision to build a power plant can be taken. This development requires long term view. Typically, it takes from 5 to 10 years to complete.
An interesting alternative approach of „modular„ development has been tested in various projects. Modularity means the option to scale up power generation little by little. Starting with smaller sized wellhead power plants from 5-10 MW which can serve as a pilot project and then expanding as the drilling continues and steam becomes available. This approach is also appealing for developers, investors, and governments, due to the fact that it speeds up the construction time and enable earlier return on investment. Furthermore, this staged development approach makes the financing easier and more attractive to investors as the revenues start to flow in much earlier, which can be used to finance the additional module investment.
The topic of direct use for heating/cooling and other residential uses is increasingly discussed in Latin America. Energy cascade can be connected to the generation plant. The direct use is though limited to only local community in the vicinity of the power plant. Good examples of food dehydration using geothermal can be found for example in Iceland, Guatemala and Mexico. Lately increased discussion has taken place of deriving rare metals out of geothermal brine.