June 8, 2009
Imagine the geothermal power plant. As long as you look at it, you will see some type of „smoke“ rising up from strange wide „chimney“. Is this real smoke? Is that real chimney? No. Right answer is that just the water steam is rising up from the cooling tower, not from chimney. Therefore the question is: Is this steam harmful for human health or is it not? In other words, does geothermal energy hurt human health?
That water steam, leaked through cooling tower, is just the small part of water steam released from steam turbine and delivered to tower in order to be cooled and liquefied, then used again for producing the steam fueling the turbine. Just the clear water, without any toxic or harmful substances.
For your better imagination, how geothermal power plant works, we recommend this short video created by CalEnergy:
[kml_flashembed movie="http://www.youtube.com/v/kjpp2MQffnw" width="425" height="350" wmode="transparent" /]
Let’s look at the health impact of geothermal facilities closer. In an simplified way, all factors can be derived from principle described above. No smoke means no need to burn fossil or other type of fuel, which means production of no emissions, toxic or harmful substances. If we talk about power plants in general, we can identify four main types of emissions:
- NOx emissions, especially Nitrogen Oxide (NO) – responsible for lung irritation, coughing, smog formation as well as for water quality deterioration.
- Sulfur Dioxide (SO2) – causing wheezing, chest tightness, respiratory illness as well as various ecosystem damages, especially acid rains.
- Carbon Dioxide (CO2) – the reason of global warming and its impact like rising the sea level, increasing the risk of damaging floods, prolonging dry seasons and accelerating glacial melting.
- Particulate Matter (PM) – causing asthma, bronchitis, cancer, atmospheric deposition as well as visibility impairment.
One case study, comparing the coal and geothermal power plant, revealed this conclusion: Coal plant updated with scrubbers and other emissions control technologies emits 24 times more carbon dioxide, 10,837 times more sulfur dioxide, and 3,865 times more nitrous oxides per megawatt hour than a geothermal steam plant.
In conclusion, geothermal power plant produces no Nitrogen Oxides as well as no Particulate Matter. In matter of Sulfur Dioxides, directly it does not emit them, but once hydrogen sulfide is released as a gas into the atmosphere, it eventually turns into sulfur dioxide and sulfuric acid. On the other hand, amount of hydrogen sulfide produced by geothermal facility ranges from 0 to 0.35 lb/MWh (in case of coal plant 10.39 lb/MWh). In addition, CO2 production is also very low: from 0 to 88.8 lb/MWh, in comparison with coal facility on level of 2,191 lb/MWh. If CO2 is produced, it is just the secondary impact linked to operational issues of geothermal complex.
As the numbers prove, geothermal power is clean source of energy in fact, producing almost none of dangerous emissions with negative impact on human health.Author : geothermania