Sabtu, Juli 04, 2009 | 0 Tanggapan Teman ?
Geothermal as complex potential.
Created by : Steven Leonardus
As we all could conclude from its name, geothermal energy is a source of heat from within the earth. The concept of geothermal energy is to heat fluid, water or brine, until it boils and changed into vapor/steam phase. Then we used the produced steam to drive the turbine which is connected to the generator, and electricity would be generated from it. Afterwards, the steam will condense into liquid form to be injected to the reservoir again, and then heated into hot water (compressed water) or saturated steam. Then the cycle continues on and on.
From the brief explanation we could imagine how easy the usage of geothermal energy is. Then questions arise, why does geothermal development still minimal in our country? As a fact that we should know is that Indonesia’s geothermal potential reached 20,000 MW, but we’ve only used 787 MW, that would be around 4%. And in terms of barrel oil equivalent, geothermal energy usage would only be 7.7 MMBOE out of 574.6 MMBOE (1999 survey). Isn’t that a loss? Is that what we called optimizing the resources?
Sadly the implementation and development of geothermal energy stumbles on the fact that Indonesia as a “rich” country have many other resources besides geothermal. Oil, gas, and mineral such as coal is a lot more worthy due to the fact that it generates more heat and it could easily be transported to someplace else. Other than that, geothermal power plant also needs huge capital to be developed and its efficiency is quite low due to the atmospheric heat loss. Due to the combination of both problems, geothermal project will give a relatively long project pay out time.
Indonesia’s sole distributor for electricity, PLN (Perusahaan Listrik Negara) ,as a major company who uses geothermal as one of it’s electric source is facing problem related to the electricity price. They need to increase the price in order to maintain profit, but due to the government regulations and the demand of most Indonesia citizen, they can’t increase the price. Due to that they keep losing profit. And in order to maintain electricity supply, the steam power plant project is going to be started. This steam will be generated through heating using coal. Yes, coal! Not geothermal, because coal heating value is greater than geothermal. So it will give a larger quantity of electricity compared to heating with geothermal.
Geothermal may not produce high heating value, but it could produce a great volume of steam. But remember that it will also need a great number of wells. The obstacle in doing so is the fact that the reservoir will heat the water influx, so if we produce from a lot of wells, the heating process would not be optimum. Other limitation is the volume of the water influx to the reservoir. It is a function of precipitation area at the surface, the greater the area the better it would be, because water would precipitate to the area and accumulates to the flow towards the reservoir. That is why geothermal resources bare found in a greenish area such as tea field, etc.
Geothermal benefits are its sustainability and clean energy resources. If we would compare the usage of geothermal energy to coal, I believe geothermal would be better, because it is a long life cycle and it doesn’t pollute environment. The price of dealing with pollution would be great, imagine if we convert it into the high investment and staging development of geothermal project, I believe it would be better if we use geothermal.
The pro and contra of the geothermal development is a complicated matter. Like they say that nothing is perfect, so does this source of energy. But in energy crisis condition like today, we should save more energy to sustain its life. That is why a sustainable energy like geothermal should be exploited and became an option, or should I say a ‘major” option. If the government regulates the electricity price which makes geothermal resource not interesting, government should give incentives to make it an interesting program.
Indonesia is a “rich” country. But what good will it does if we don’t know how to use it? A question which should soon finds its answers, before everything is too late.
Pemikiran tentang : teknik geology