World Environment Day 2023 | The indies dig deep to harness its geothermal energy

India’s energy demand is reported to be the highest globally for 2021-30, and the country is pushing the addition of renewable energy capacity to achieve the twin objectives of energy security and emissions reductions. While the country estimates there is potential to develop 10 gigawatts (10 GW) of geothermal capacity, this segment has received little attention in India’s ambitious green plans.

India plans to add 500 GW of renewable energy capacity by 2030, most of which will come from wind and solar power. The country has made small steps in the geothermal sector. But can the country push geothermal energy as vigorously as it has added solar and wind power? Before analyzing the opportunity, let’s try to understand what geothermal energy is.

Geothermal energy involves harnessing heat from deep within the earth’s crust. Deep wells are equipped with turbines that convert steam into electricity, which is then connected to an electrical grid.

While countries like the US, Indonesia and the Philippines have conquered this energy sector, India is still catching up. From deserts to mountain peaks, India has immense space for geopower. The Geological Survey of India has calculated that India has the potential to benefit from around 10 GW of energy from geothermal resources. The energy generated could be used to supply electricity to settlements in difficult terrain and gradually replace dependence on fossil fuels.

Story so far

Through short hole drilling in the 1970s, the Geological Survey of India has estimated about 350 sites in the country that have the potential to generate geothermal energy, with Ladakh being the most promising location. Oil and Natural Gas Corporation Ltd (ONGC) pioneered the establishment of this set-up in India. They recently attempted to drill two wells in the Puga Valley in Ladakh.

There are many ifs and buts below, but let’s not get discouraged. First we need to establish that geothermal potential exists in India, said Ravi, director general of the ONGC Energy Center Trust.

Drilling began on the Puga Valley project in August last year, a partnership between the Maharatna Public Sector Unit (PSU) ONGC and the Icelandic company ISOR. The team reached a depth of 40 meters which measured a temperature of 140 degrees Celsius. The cuts of quartzite, pyrite and silica discovered there indicate a reachable temperature of at least 200 degrees Celsius, given that these crystals only form in that temperature range. However, due to shallow basin activities, poor weather conditions, equipment and chemical requirements, drilling was abandoned.

Ravi said drilling at such high elevations can be challenging as there is a small window of time where the weather allows for exploratory activity. ONGC plans to complete two-stage drilling of the wells between August and October this year at Puga and Chumathang, 12 kilometers apart. If the two reservoirs are interconnected, it could form a mega reservoir with a geothermal potential of 200 megawatts. This project could change the face value of Ladakh, Dwivedi said.

We are very confident that when we go to our target depth of around 1000 meters, the temperature will definitely be around 220 degrees Celsius,” Ravi said.

Water boils at lower temperatures at higher altitudes, thus furthering the possibility of exploiting steam in these places. ONGC has signed a memorandum of understanding with the Ladakh administration for the installation of a 1 megawatt plant in Puga. Testing the reservoir will determine its potential, type of reservoir, needed turbines, etc. A pilot project in India, Puga and Chumathang will set a standard for further projects to come and establish the capacity and economic viability of geothermal energy in the country.


How does geothermal compare to solar or wind energy in terms of cost of production?

Ravi did not comment on this question when asked, stating that it is a pilot project in India. First the potential must be established, only then can the costs be ascertained. However, according to a report by the International Renewable Energy Agency, these are the levelized costs of electricity (LCOE) for (as of 2020)

1. Onshore Wind: $0.041/kWh,

2. Geothermal Energy: $0.07/kWh GE

3. Solar PV: $0.057/kWh

So, geothermal is a bit more expensive, but as markets and technologies evolve, the price should come down, just like they did for solar which was around 16 per unit 10 years ago and less than 3 now, added Ravi.

When asked about the environmental impact of drilling so deep in regions like Ladakh, Ravi did not mention any harmful effects of drilling on the environment as it happens deep below the earth’s surface.

According to the US Energy Information Administration (eia.gov), there are some disadvantages mentioned compared to drilling oil wells. “Exploration and drilling for oil can disrupt terrestrial and marine ecosystems. Drilling an oil well on land often requires clearing an area of ​​vegetation. However, technologies that significantly increase the efficiency of exploration and drilling also reduce the effects on the environment”.

Rocky road ahead

The creation of geothermal wells is a capital intensive project. ONGC is also planning to start another R&D project in the Gujarats Cambay area, which requires drilling to a depth of 3,000 meters.

Benson Ireri, Africa Lead at the World Resources Institute (WRI), said the two main reasons for the lack of emphasis on geopower are a research and funding deficit. I think the cost risk for that, is the amount of investment that has to go in terms of exploration, when you find, say, a single well, it’s financially feasible, it’s a big gamble, he explains.

And drilling one well costs about $5 million (about Rs 41.2 crore), according to the US government’s Geothermal Technologies Office. Only after a project has been successfully executed can rates and other cost-economy factors be determined. From a research perspective, I think being able to see how and what can be done, in terms of research, and come to build a better understanding of the industry, could also be one of the key things that further help to move forward in this space, said WRI’s Ireri.

Hellisheii Power Station in Iceland. Geothermal power stations are compact, have a low carbon footprint and use less land per gigawatt hour than coal (3642 sq m), according to the US Department of Energy. (Photo by Kevstan via Wikimedia Commons 4.0)

Learnings from other developing nations

Kenya is the world’s seventh largest producer of geothermal energy, with an operating capacity of 800 megawatts. What kickstarted Kenya’s geothermal energy journey was a government hunt in the early 2000s for alternative renewable resources, as hydropower was unreliable during droughts. Talks with private investors led to the formation of the government-owned Geothermal Development Corporation (GDC) in 2008, with financial backing based on loans from the World Bank and African Development Bank. The GDC assumed responsibility for the risks associated with experimental drilling, which attracted private investors to conduct GE drilling operations. Foreign investment such as that from Japan followed soon after. Since then, Kenya has also introduced geothermal energy courses at universities to train its people for the industry.

Ireri said partnerships between drilling companies and universities can enhance research in the field, with grants as additional incentives. India can learn from Kenya and take similar steps, adapting to the demand and thresholds of the subcontinents.

The benefits of geopower are many. Since it is harnessed from deep beneath the surface of the Earth, it is a continuous source of energy. Solar and wind, on the other hand, are variable renewables, fluctuating with weather conditions. Geothermal power stations are compact, have a low carbon footprint and use less land per gigawatt hour than coal (3642m2), according to the US Department of Energy. Energy experts believe that geothermal energy can complement the high energy requirements of green hydrogen production.

As India aims for net zero carbon emissions by 2070, it could close the energy gap and help India build a diversified clean energy portfolio.

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