Review of Special NQ Academy Webinar #10: Technology & Innovation to Accomplish Geothermal as Affordable Energy

NewQuest Goetechnology has been held a Special NQ Academy Webinar as the first event in the NQ 10 Years Anniversary agenda series. In its 10 Years Anniversary, NQ organizes several competitions such as Photo & Video Competition, Young Geothermal Explorationist Competition, and Software Developer Competition. Besides the competitions, several special agendas that will be held, including Special Webinar, Special Training, Special Workshop, and Special Anniversary Day.

The Special NQ Academy Webinar #10 was held on September 4, 2021. The webinar was hosted by Dr. Yunus Daud, Founder of NewQuest Geotechnology. The event was discussing an interesting topic about “Technology & Innovation to Accomplish Geothermal as Affordable Energy” presented by Mr. Riza Pasikki M.Sc. He is COO & CTO at KS Orka Renewables, Pte. Ltd.

In his opening, Mr. Riza Pasikki explained that the world needs energy to run its activities. The fulfillment of energy needs must meet two requirements such as Reliable, and Affordable. Currently, we have the third requirement, that is clean energy. What about geothermal?

Geothermal, when compared to other renewable energies, such as wind and solar energy, does not depend on weather conditions which could change the intensity of the energy. Affordable geothermal energy is still a debatable thing, since there are opinions at this time that the price of geothermal still tends to be expensive. In this webinar, it is explained how the efficiency has been carried out by KS Orka in terms of geothermal exploration and operations. Which in the end, it can reduce geothermal prices.

In Indonesia, there are 3 pillars that are being carried out by KS Orka, first is Organic Growth. It means that KS Orka is maximizing the value of assets that have been operated, namely Sorik Marapi and Sokoria, the target is to be able to fulfill PPA with PLN of 270 MW. The second is Inorganic Growth, KS Orka also seeks merger and acquisition, or co-develop the other geothermal projects. The  third is Technology Provider, because Kaishan is a power plant developer, our business also helps Kaishan provide reliable geothermal powerplants.

SMGP has reserves of 240 MW, PPA tariff with PLN is 8.1 cents/kwh, which is still below North Sumatra’s BPP of 10.18 cents/kwh. SMGP plan to build in 5 stages of development which is currently produces 90 MW. The fulfillment of 240 MW is planned for COD unit 5 in Q3 in 2024. There are 32 wells with 18 of production wells and 14 of reinjection wells. The average production well capacity is about 8-9 MW per well. The steam and brine are ready for SMGP unit 3.

In Sokoria Geothermal area, the BPP in Flores is 17.58 cents/kwh while the electricity tariff from the Sokoria PLTP is 12.5 cents/kwh. Total reserves are 30 MW with planned staging development for COD unit 1 of 5 MW in October. Final COD unit 4 is planned to be carried out in 2025.

The application of technology and innovation application covers several aspects, those are Resource Development (characterization and development plan), Resource to Production (drilling the wells), and Energy Conversion (converting heat to electricity generation).

During Resource Development, several things need to be considered, such as Reservoir Characterization (explorations, drilling, well testing & analysis, surveillance & analysis), Development Plan (modelling, well targeting, production & injection strategy), the approach which used is internalized the resources from logging units, TFT, & subsurface teams.

At the drilling stage, KS Orka looked at several benchmarks in geothermal drilling and measured how competitive the wells produced by KS Orka were. For Indonesia database, the drilling cost is around USD 3,500/m. KS Orka always carries out continuous improvement both in terms of contracts that are bundled contracts, IPM & discrete contracts. From the application of this type of contract, there is a decrease in cost from USD 3,000/m to USD 2,427/m. Currently, KS Orka operates 2 rigs simultaneously, bringing the drilling value down to USD 1,600/m with a discrete contract made with the each service companies. KS Orka continues to make improvements in cost efficiency, and KS Orka can achieve the lowest value from the AAE-02 well with total depth of 2,200 meters worth of USD 1,180/m.

Regardig enrgy converson, there are 2 options, wellhead (modular unit) or centralized unit. There are some differences between the two types in terms of resource utilization, technical flexibility, construction time, land used, speed to generation, and financing. KS Orka currently uses the modular unit on Sorik Marapi and Sokoria.

There are 2 ways to convert heat to electricity generation, by using steam and brine. In terms of steam utilization, KS Orka used  Cascaded Steam Expander and Steam Organic Rankine Cycle (ORC). This is the combination of a modular steam screw expander and a modular ORC power plant. This system has high thermal efficiency as well as eliminate the gas removal system (NCG vacuum pump).

Brine is also used as a heat source. The technology used is the brine ORC or generally known as binary system. It needs 250 kg/s hot brine with inlet temperature of around 170 ⁰C and produces an outlet brine of 80 ⁰C. With this system, 7 MW of electricity can be generated.

The benefits that have been obtained are incremental generation (7 MW from 250 kg/s of brine) and increased injection capacity without adding injection wells. However, some challenges occured, that is Silica scaling which can be mitigated by scale inhibitor treatment with a cost of USD 15k – 20k per month. Another challenge is cooling breakthrough, but it also can be mitigated by reservoir management.

KS Orka uses Screw Expander in electricity generation as the “heart” of the wellhead unit. This system is a positive displacement machine. It has a simple structure, less moving parts, and reliable. It can accommodate wide application ranges pressure from 3 – 30 bar flow rate. This turbine is not sensitive to liquid droplets, small solid particles and NCG. The turbine also has high isentropic efficiency, no steam uses for the ejector.

In his closing remarks, Mr. Riza conveyed several messages. Technology and Innovation in clean & renewable energy are the result of our own strong desire to lead a better life. KS Orka continuously looks for opportunities to leverage our experience, innovation, and unique technology in the country for a better and greener Indonesia.

The audience was very enthusiastic about the subject that has been presented. The technology and innovation that have been carried out by KS Orka give a new insight in Indonesian geothermal development. Hopefully, KS Orka’s achievements can inspire other geothermal developments in Indonesia.