Like many island nations, the Comoros seeks to construct a sustainable and vitality safe future round geothermal with a primary undertaking deliberate in Karthala.
In late 2023 and once more in the summertime of 2024, Steam Srl (STEAM) accomplished two assignments to de-risk the Mount Karthala Geothermal Mission within the Comoros. Commissioned by the Bureau Géologique des Comores (BGC) and supported by the United Nations Improvement Programme (UNDP) Comoros and UNDP Rome Centre for Local weather Motion and Power Transition, the undertaking has the potential to turn out to be the primary geothermal energy plant within the Comoros, and to make the Comoros the third African nation with an operational geothermal energy plant.
STEAM’s work confirmed the viability of the potential geothermal useful resource after which additional confirmed the presence of enough groundwater close to the drilling web site to assist each deep exploration actions and serve the island as a safe water supply for the long run. The undertaking findings are anticipated to assist unlock new funding for the Mount Karthala undertaking, which has been in growth since 2008.
Geothermal growth in island nations: A strategic benefit
The Mount Karthala undertaking is a major growth within the context of geothermal vitality for island nations. Islands just like the Comoros face distinctive vitality challenges resulting from their reliance on imported fuels, which makes vitality each costly and weak to provide chain disruptions. Geothermal vitality affords a sustainable, domestically sourced various that enhances each vitality safety and financial stability.
For the Comoros, growing its native geothermal vitality sources might be transformative. Positioned within the Mozambique Channel, the nation depends closely on diesel turbines and biomass for electrical energy and heating. With its volcanic exercise, significantly round Mount Karthala, the Comoros holds important untapped geothermal potential. The profitable identification of groundwater sources as a drilling assist brings the nation one step nearer to realizing this potential, aligning with broader international targets of the vitality transition such because the UN SDG 7 (Reasonably priced and Clear Power), and decreasing carbon footprints.
The historical past of geothermal within the Comoros
The Comoros islands started their geothermal journey in 2008, when consultants from Kenya Electrical energy Producing Firm (KenGen) carried out geoscientific research that confirmed the realm’s geothermal potential. Six years later, the Bureau Géologique des Comores (BGC) performed research with the assist of a number of consultants and repair suppliers. The outcomes indicated that the realm has the potential to generate greater than 45 MW of geothermal energy.
Following the examine, the Comoros secured commitments from Geothermal Danger Mitigation Facility (GRMF), the International Setting Facility (GEF) and different donors and financiers to proceed with the exploratory drilling, paving the way in which for a monetary shut because of a marketing strategy that outlined a transparent path to profitability.
One of many best hurdles to creating a convincing argument that the Mount Karthala undertaking is viable rests within the potential to assist exploratory drilling utilizing floor water, with anticipated anticipated water provide wants of three,000 liters per minute for 60 days. Though the Grande Comore Island is characterised by plentiful rainfall of between 1,500 and a couple of,000mm/yr, as much as 4,000 mm/yr within the Mount Karthala space, the infiltration fee is estimated round 95%, that means a lot of the precipitation flows into the underground and never into the ocean.
Nevertheless, a lot of the nation’s wells are close to the shore, making it unfeasible to pipe water as much as the drilling space. Consequently, it was vital to analyze the hydrogeological setting of the interior zones of the volcanic items of Mount Karthala to offer the required water provide.
De-risking the reservoir mannequin and the hydrological mannequin
STEAM’s involvement within the Comoros undertaking, along with its accomplice GEL Power, was divided into two strategic phases. Within the first section, working in collaboration with UNDP Comoros and native stakeholders, STEAM’s group reviewed the present useful resource assessments and undertaking plan, after which developed an in depth roadmap for shifting the undertaking ahead to the exploratory section. On this section, STEAM collaborated with Geothermal Engineering Ltd, the consultants in undertaking growth and funding behind the profitable United Downs geothermal undertaking applied in Cornwall (UK).
Within the second section, STEAM geologist Lorenzo Favaro labored with Viridien Group and Phoenix Geophysics to execute a two-week capability constructing agenda and hydrogeological examine. This section confirmed the validity and integrity of the sphere testing devices by a category and discipline coaching workout routines for the BGC group.
As soon as adept in using the devices, the undertaking group executed an built-in magneto-telluric (MT) survey, which comprised an expanded discipline of 24 MT further websites, extending the 3D resistivity mannequin in the direction of the northern space of the island. The expanded testing space aimed to develop the unique mannequin constructed by BGC in 2015, shifting the main target to the shallower layers on the northern aspect of the volcano with a view to verify the feasibility of shallow water wells, between 250 and 300m, foreseen in earlier research.
The outcomes of Section 2 confirmed that it’s affordable to anticipate a water desk depth of roughly 230-300 m g.l. in accordance with the unique projections, although it additionally indicated that some wells would want to go deeper.
Skilled perception from STEAM’s Senior Geologist
Lorenzo Favaro, STEAM’s Senior Geologist and lead for the undertaking, emphasised the significance of a complete method in geothermal undertaking growth: “Buying new knowledge in tropical forests and inaccessible areas was a novel and making an attempt expertise, with many hours of strolling, even at night time. However all knowledge—geological, logistical, and environmental—contribute to de-risking a geothermal undertaking.”
“A multidisciplinary firm like STEAM, with our lengthy and numerous expertise, has the potential to work with all undertaking stakeholders to construct the whole datasets required to maneuver previous the floor exploration section. With out this step, the deep exploration and subsequent design and building phases of a geothermal plant are futile.”
Supply: E-mail correspondence
