Of the various forms of green energy, geothermal power is the least popular when compared to solar and wind. For example, with the wind energy capacity in the US increasing by over 13 GW in 2012 and 5.5 GW of the total coming only in December, the Geothermal Energy Association reports that 147.05 MW capacity was added to the geothermal energy base in 2012, representing a 5% increase over 2011.
In comparison, the geothermal power capacity increase is marginal, at best, but there are some few advantages geothermal has over other renewable sources of energy. The key one is the fact that geothermal energy produces energy constantly in spite of weather.
That contrasts with solar and wind which give intermittent power. Although with grid-scale batteries, this shortage could be overcome, having some constant supply included is not a bad thing. The important thing now is to cut costs and make sure a proper understanding of geology to prevent problems.
Among the geothermal power projects that started operation in 2012, the John L. Featherstone Plant in California takes the lead with 49.9 MW generated in the year. The GEA states that there are 13 extra projects near completion which could come online later this year.