I want to share knowledge I got from International Student Energy Summit 2015. There was a parallel session about Geothermal Energy driven by three keynote speakers: (1) Masami Nakagawa, Associate Professor at Colorado School of Mines, Department of Mining Engineering (2) Triharyo Indrawan Soesilo, President & CEO Supreme Energy and (3) Chris Bromley, Chairman of IEA Geothermal.

Geothermal energy has ancient roots. The Romans used it to heat buildings in the city of Pompeii, and in medieval times people fought wars over lands with hot springs. Geothermal is believed to be a readily available, abundant source of clean energy and an attractive alternative to fossil-fuel power and thermal energy in our current system. Global geothermal production is predicted to experience a twentyfold increase between now and 2050, but at the moment it is experiencing slow growth and these expectations are riddled with challenges. It is needed to address barriers relating to economics, regulations, market facilitation and R&D support.

The Benefits of Geothermal Energy

Geothermal energy is created by the heat of the earth. It generates reliable power and emits almost no greenhouse gases. This is how it works: When groundwater seeps below the earth's surface near a dormant volcano, the water is heated by reservoirs of molten rock, usually at depths of up to 9,800 feet (3,000 m). Once captured, steam and hot water are separated. The steam is cleaned and sent to the power plant and used to turn turbines that generate electricity. The separated water is returned to the reservoir, where it helps to regenerate the steam source.

In addition to providing clean, renewable power, geothermal energy has significant environmental advantages. Geothermal emissions contain few chemical pollutants and little waste—they consist mostly of water, which is reinjected into the ground.

Geothermal energy is a reliable source of power that can reduce the need for imported fuels for power generation. It's also renewable because it is based on a practically limitless resource—natural heat within the earth. The electricity produced by our geothermal power operations is sold to local power grids, providing clean energy to fuel the growth of some of the world's most rapidly expanding economies.

Indonesia Geothermal Profile and Status

Indonesia position to the Ring of Fire gives big potential of geothermal energy. 276 locations with geothermal energy potential had been identified that is estimated to have resources sufficient to generate 29 GW of electricity, which equates to 40 per cent of the world?s geothermal reserves.

Indonesia currently produces the third largest amount of geothermal power, after the U.S. and the Philippines. Still, it's tapping less than 5 percent of its potential 29-gigawatt capacity. It has 62 projects under way, and if all get built, Indonesia could overtake the Philippines by the end of this year and the U.S. in another decade or two, according to a 2015 industry analysis by the Washington-based Geothermal Energy Association.

Potential:

1. Hosts 40% of total world?s potential, Al Gore said that Indonesia is likely to be a ?geothermal super power? in the future
2. Optimumutilization will significantly reduce dependence on fossil fuel, reduce GHG emission and improve national energy security
3. Geothermal utilization would reduce energy subsidy by avoided oil consumption

Barriers:

1. Higher price compared to the least-cost-options (e.g.coal power plant). Developers of geothermal power plant can spend millions of dollars just to build access roads to exploratory wells that might not deliver enough steam to make a project pay off.
2. High up front risk in exploration stage (Reflected in higher energy cost lowering competitiveness to the least-cost-options Big owner-investment needed, limiting the playing field)
3. Land-use issues e.g. when situated in protected forest, cultural site, water availability, etc.
4. Lack of geothermal experts (Indonesia has less than 10 geothermal experts)

These barriers cause the development of geothermal energy in Indonesia to slowdown. However, it is good opportunity for young generation to be geothermal experts because it will be promising in future. CEO of Supreme Energy stated three major studies needed by geothermal developers: geophysics, geochemistry

Also promising is multimillion-dollar funding from the World Bank and other development groups, including Climate Investment Funds. In September, at the UN Climate Summit in New York City, Indonesia joined the U.S. and 22 other countries to form the Global Geothermal Alliance, aimed at reducing the financial risks of exploratory drilling.

Last year state government amended a law to stop defining geothermal development as "mining" and thus allow work in certain forest (protected forest is still cons), where many resources are located. 

Source:

http://news.nationalgeographic.com/news/energy/2015/03/150303-geothermal-power-wayang-windu-indonesia/

http://www.geo-energy.org/pressReleases/2015/Geothermal_Global_Grows_Feb_2015.aspx