Geothermal energy is greener alternative: Analysis
S Vishnu Sharmaa, INN/Chennai, @Svs037
Geothermal energy, that uses earth’s heat to generate power is better than photo voltaic energy when it comes to carbon-di-oxide emissions, says a research.
The research was taken up by Indian Institute of Technology, Hyderabad (IIT-H) in association with Monash University in Australia. The research further pointed out that a combination of renewable energy technology must be adopted in this era of dwindling fossil fuel reserves and increasing greenhouse gas emissions.
This analysis was undertaken by Professor D. Chandrasekharam, Department of Civil Engineering, IIT Hyderabad and Professor G. Ranjith Pathegama, Department of Civil Engineering, Monash University.
Their Research paper was published recently in the reputed peer-reviewed journal ‘Geomechanics and Geophysics for Geo-Energy and Geo-Resources.’
Their study involved lifecycle assessment of renewables. Around 10 tonnes of quartz is needed to manufacture solar cells that can generate 1 megawatt of electricity from Sun. About 1 MWe of electricity can support about 20,000 people annually.
Chandrasekharam said While solar power does have benefits over conventional energy sources, the hype surrounding its apparent ‘greenness’ has to be analysed. For, solar power is not the zero-emission energy source as it is perceived to be.
The quantity of quarts that has to be mined to support millions of people across the globe. A Solar pv cell involves two important stages, namely producing metallurgical grade silicon (MGS) and producing electronic grade silicon (EGS) from quartz.
While the first stage witnesses release of 1756 thousand tonnes of CO2, a similar amount of CO2 is released during the conversion of EGS to ingots, said Chandrasekharam.
While alternative energy sources like solar power are being widely considered among the green energy technologies, no type of energy can be completely environmentally neutral.
A comprehensive assessment of all costs and benefits must be undertaken for all green energy technologies, he said. Unlike other renewables, geothermal energy can supply base-load electricity. The waste after its life cycle, unlike solar PV is negligible.
The best way to go forward is to choose a combination of technologies that can minimize harm to the environment not chase the horizon of zero harm, say the researchers.
