In the 'Positive Pre-Feasibility Study & Reserves Declared' announcement released on 31 March 2026 at 7:00:08 under RNS No 7179Y the lithium recovery rate of 90.0% used in the reserves reporting has been adjusted to 85.5% to be consistent with that reported for the process plant. This affects the modelled average brine feed rates and the adjustments made in this RNS are as follows:

All other details reported in the RNS No 7179Y remain unchanged. The resulting adjustment to brine feed rate has no impact on the lithium reserves reported or any other aspect of the PFS or the economic evaluation of the project.

The full amended text (with amendments identified in bold) is shown below.

14 April 2026

CleanTech Lithium PLC ("CTL", CleanTech Lithium" or the "Company")

Positive Pre-Feasibility Study Completed and Reserves Declared for Laguna Verde

Pre-Tax NPV₈ US$1.37bn and IRR of 24.2%

CleanTech Lithium (AIM: CTL, Frankfurt:T2N), an exploration and development company advancing sustainable lithium projects in Chile, reports the results of its independent Pre-Feasibility Study ("PFS") for the Laguna Verde project (the "Project"). The PFS demonstrates positive technical foundations and compelling economic outcomes of the Project at PFS level, marking a significant milestone in the Company's development pathway. Completing the PFS, which includes the first declared JORC (2012) compliant reserves, enables CTL to accelerate engagement with potential strategic partners.

The Company is now in a position to share the results of the PFS with selected parties after it was announced that CTL and the Chilean Government agreed the contractual terms of the long-term Special Lithium Operating Contract ("CEOL") for Laguna Verde, which is subject to final ratification by the Comptroller General's Office, as announced on 10 March 2026.

Laguna Verde PFS Highlights:

·    The PFS demonstrates production of 15,000 tonnes per annum ("tpa") of battery grade lithium carbonate for an operating life of 25 years with positive economic performance based on the assumptions applied in the PFS.

·    The economic results are based on preliminary engineering and economic assessments and are subject to risks and uncertainties, including lithium price variability, process performance, permitting outcomes and project execution.

·    The PFS, led by leading engineering firm Worley as study integrator and supported by additional independent specialists, bases the Project´s process design on a Direct Lithium Extraction ("DLE") technology with prior commercial deployment experience and a standard downstream process to final lithium carbonate product.

·    The study demonstrates the Project's advantages with a high level of optionality for plant design and power supply, very high-water recovery, which is a critical path item for mining projects in Chile, and strong community engagement and environmental progress.

Ignacio Mehech, Chief Executive Officer, CleanTech Lithium said: "The completion of the PFS is a major achievement for CleanTech Lithium and the work demonstrates the Laguna Verde Project has very strong technical merits and highly favourable economics. The estimated Capex intensity of approximately US$49,900 per tonne of battery grade lithium carbonate compares favourably with DLE projects in development globally, and the estimated Opex places the project in the lowest cost quartile for the industry, leveraging Chile´s advantages in infrastructure, logistics and a large highly skilled workforce. The depth of work completed to date places the Company in a highly favourable position as we have the unique opportunity to become the next lithium producer to come online in Chile after more than 30 years.

The Board believes that Laguna Verde is a highly attractive opportunity for strategic partners seeking long-term lithium supply at a time when global demand is growing rapidly and not enough projects are being developed to meet forecast demand. Completion of the PFS allows us to kickstart the process of selecting a strategic partner to fund and develop the Project, with our already engaged consultant Cutfield Freeman & Co.

As promised, we end Q1 2026 very strongly after having agreed the long term CEOL, released a PFS with very attractive economics and begun a strategic partner selection process that we believe will be very competitive, given the historical interest our project has drawn from such parties. What lies ahead is an exciting period, as we will look to begin preparing the Environmental Impact Assessment ("EIA"), seeking to dual-list on the ASX and begin preparing for the Definitive Feasibility Study ("DFS"), all the while completing the strategic partner selection process by year end.   

I am really enthusiastic for CleanTech Lithium, our shareholders and me personally, as we have delivered on our promises and can now finally begin the next stage of development of Laguna Verde. I look forward to updating our shareholders in the coming days on the merits of our PFS and our plans to unlock the real potential of our flagship project."    

Pre-Feasibility Study

The PFS was led by the study integrator, who coordinated the work of third-party consultants and information provided by the Company.

Major third-party contributors to the study include:

·    Montgomery & Associates - Geology, hydrogeology, resources, reserve modelling and wellfield design

·    Xi-an Lanshen New Material Technology Company ("Lanshen") - Process design and engineering, process capital and operating cost estimates

·    Ad Infinitum - Process design review, flowsheet development and processing technical oversight (Competent Person - Processing)

·    Benchmark Minerals Intelligence - Lithium product marketing studies

·    Worley - Project infrastructure engineering and infrastructure capital and operating cost estimates, construction planning and financial modelling

Process design inputs were developed by Lanshen and reviewed and integrated by Ad Infinitum, whose principal acted as the Competent Person responsible for processing. Worley´s role was focused on infrastructure, engineering,  and cost estimation whereas Lanshen was primary responsible for process design.

The PFS incorporates inputs from third-party specialists, including process design, hydrogeology and market analysis, which have been relied upon for the purposes of the study. The study integrator has not independently verified all third-party inputs and does not accept responsibility for such information.

Project Overview

The Laguna Verde Project is located in the Atacama Region, Chile, at elevations exceeding 4,300 metres above sea level. The Project is situated approximately 265km east of the regional mining centre of Copiapó.  A paved highway Route 31 which extends from Copiapó through to Argentina, runs through the project area. The proximity to the international border and established transport corridors supports logistics for equipment supply, reagent importation, and export of finished product.

As part of the PFS process a plant location trade-off study was undertaken as announced to the market on July 02, 2024 (Link). The study resulted in the decision to locate the downstream Lithium Carbonation Plant ("LC Plant") in Copiapó, and the plant for the DLE and eluate concentration stages which produce a concentrated lithium chloride (LiCl) solution, at the Laguna Verde project site, as shown in Figure 1.  This configuration greatly reduces the footprint at the project site, from power supply, storage, camp and plant facilities, along with construction phase and environmental impacts. With approximately 70% of the operational workforce employed at the carbonation plant, locating it in Copiapó provides major advantages in accessing a skilled workforce, along with existing infrastructure, power supply and other inputs. This carbonation plant could be expanded to process LiCl from additional future projects in the region.

Figure 1: Regional Map and Plant Locations

Project Configuration and Recovery Method

The proposed development for production of 15,000 LCE comprises two project sites:

Laguna Verde Site - LiCl Production:

o  Lithium chloride (LiCl) production facility

o  Brine extraction and reinjection wellfields

o  Raw brine handling and DLE processing

o  Concentration and purification to produce a transportable LiCl solution

Copiapó Site (conversion to 15,000tpa battery grade lithium carbonate):

o  Lithium carbonate (Li₂CO₃) conversion facility

o  Final product drying, micronizing and packaging

The Process Block Diagram further details this configuration by showing an overview of the recovery method as presented in Figure 2 below.

Figure 2: Process Block Diagram

Laguna Verde LiCl Plant

At the Laguna Verde project site brine is extracted from the production wellfield and pre-treated to control suspended solids prior to DLE processing. For the PFS, the Company selected the DLE adsorbent provided by Lanshen after extensive test-work on various adsorbents. Lanshen´s provides an alumina-based adsorbent which is the most commercially established DLE adsorbent, and it has been a leader in commercial deployment in the DLE sector.

Figure 3: Lanshen Commercial DLE Unit in China

In the DLE process lithium is selectively recovered by passing the feed brine through columns filled with the adsorbent.  The columns are arranged in a carousel system, a commercial scale example of which is shown in Figure 3. Lithium is desorbed with demineralised water to produce a dilute LiCl eluate, which is subsequently upgraded through a staged purification and concentration circuit.

At the Laguna Verde site the plant will produce a LiCl solution that is approximately 5.88% lithium, suitable for bulk transport to Copiapó for carbonate conversion. Depleted brine and process effluents are managed through integrated water recovery systems and reinjection into the basin aquifer to minimize net freshwater consumption and aquifer depletion.

The key recovery parameters achieved at the Laguna Verde LiCl plant are:

·    DLE lithium recovery: 90.0%

·    Membranes recovery (RO-NF-ED) + IX: 98.4%

·    LiCl Plant total recovery: 88.6%

Copiapó Lithium Carbonate (LC) Plant

The concentrated LiCl solution is transported to Copiapó and converted to lithium carbonate using soda ash (Na₂CO₃) carbonation at approximately 85°C. The conversion process includes:

·    Carbonation reactor,

·    Solid-liquid separation,

·    Hot washing,

·    Drying and micronizing to meet battery-grade specifications,

·    Mother-liquor recovery circuit for lithium recovery and recycling.

The recovery achieved in the carbonation stage is 87.2% however the design achieves incremental recovery from the mother-liquor circuit that results in total recovery from the Lithium Carbonation Plant of 96.5%.

Based on the total recovery rates of the LiCl plant of 88.6% and the total recovery of the Lithium Carbonation plant of 96.5%, the global recovery rate for the process is 85.5%. The flowsheet is designed around high internal water recovery. Key features include:

·    RO/NF/ED-based water recovery systems,

·    Evaporation condensate reuse,

·    Reinjection of depleted brine and treated effluents.

From an environmental perspective, the absence of conventional evaporation ponds and reliance on reinjection represent a fundamental design feature intended to reduce long-term disturbance.

Project Infrastructure

The infrastructure framework supporting the Laguna Verde Project comprises the two primary sites and associated logistics corridors. Product export and most reagent imports are expected to be routed via Angamos Port (Mejillones). Various other port options were assessed, and it was considered based on current available capacity to be the superior option. This will require further evaluation.

Figure 4: Plants and Port Location

Laguna Verde Site Infrastructure

The LiCl Plant facilities will be situated northwest of the Laguna Verde, as illustrated in Figure 5, with remaining infrastructure spread around the periphery of the laguna, mainly being:

a)            Brine extraction wells.

b)            Industrial facilities area for reagent/utilities.

c)            Concentrated LiCl brine storage tanks for truck transport to the LC Plant. Two (2) tanks are considered, with a storage capacity of 500 m³ each (operational volume), from where the trucks are loaded, to transport the brine to the LC Plant.

d)            No solid discards are generated from this plant, and all liquid discards are mixed with the spent brine for reinjection.

Figure 5: Area of the LiCl Plant infrastructure

For the production of concentrated LiCl eluate with a capacity of 15,000 tpa LCE, the plant´s permanent installations are configured as depicted in Figure 6. The central area marked as DLE plant comprises the DLE modules which total 10 carousels each with 30 columns.

Figure 6: Main installations and facilities for LiCl Plant.

Electrical and Thermal Power

Electricity represents the primary energy input for the project. The electrical consumption for the plants at the Laguna Verde site and at Copiapó is estimated as below, with the former having a much larger requirement:

·    Laguna Verde (LiCl plant): 175,200 MWh/year

·    Copiapó (Li₂CO₃ plant): 19,200 MWh/year

Electricity and thermal energy consumption have been estimated based on data supplied by Lanshen and supplemented with engineering estimates for auxiliary equipment and plant utilities. The consumption values are used to calculate annual electrical and thermal energy costs for the project. The energy basis includes:

·    Electrical demand for motors, pumps, compressors, wellfield pumping, instrumentation, and general services.

·    Thermal energy requirements, including LPG consumption for boilers and saturated steam generation.

·    Diesel usage for vehicles and mobile equipment at both plant sites.

·    Market-based unit pricing, derived from Chilean energy market data and preliminary supplier information for LPG and diesel.

A number of options were evaluated for the supply of electricity to the Laguna Verde site. Based on the technical information provided by CleanTech Lithium, a non-binding reference proposal was prepared by an established power transmission company in Chile. The proposal is based on a Build-Own-Operate-Transfer (BOOT) model.

The operating time of the electrical supply is considered for the years of operational life of the project. The BOOT proposal would deliver the required electrical supply to the Laguna Verde site via a 220 kV transmission lines and a step-up substation.  This will be a length of 130 km and follow the route of the national highway 31, as shown in Figure 7, from a connection point near the existing La Coipa substation to the Laguna Verde plant. Alternative routes will be evaluated in future stages of development.

Figure 7: Route of Electrical Transmission Line based on Reference Proposal

The Chilean national electricity grid has one of the highest renewable energy penetration rates globally. As a result, the Company will be well positioned to secure a BOOT agreement for 100% renewable energy. In addition, the Company undertook several studies or proposals to evaluate other options related to the energy requirements of the project, across electrical supply, gas or alternative heating technologies, and transport fuel.  A major consideration in undertaking this work was the potential to maximise the sustainability of the energy input required for the project.  These evaluations included:

·    A study on utilising onsite renewables comprising a solar photovoltaic power plant, wind turbines and a battery energy storage system to provide the full electrical energy requirements at the project site

·    Evaluation of solar thermal, or concentrated solar, technologies to provide the heat and steam energy requirements at the Project site. 

·    A desktop study was completed on the potential for geothermal energy to provide the heat and steam energy requirements at the Project site. Laguna Verde is a recognised site for geothermal energy potential in Chile.

·    A proposal was received for utilising electric trucks for the transport of eluate from the project site to the downstream processing plant at Copiapó. This would take advantage of a very large altitude gradient between the two sites, which provides regenerative charging when transporting heavy loads down gradient and a much lighter load on the return.

These studies or proposals provided valuable ideas and insights that will be further evaluated at the next stages of project feasibility studies.

LPG

Liquid petroleum gas (LPG) is to be used in the project as a heat energy source, specifically for the boiler at the LiCl Plant and for the boiler and dryer in the LC Plant. This utility will be obtained locally and transported to the plant by trucks.

Process Water

Water mass balances were completed for each of the plants at the Laguna Verde Site and at Copiapó, and the consumption of water is as follows:

·    LiCl Plant: 160,800 m³/y (5.6 L/s)

·    LC Plant: no industrial water is required during normal operation due to recirculation of all water within the process. Water is specifically required for start-up.

There are several options available for supply of process water under evaluation. Firstly, surface water courses that contribute to the Laguna Verde. The Peñas Blanca River flows from west to east and has a continuous flow throughout the year, while to the east of the Laguna Verde, there are intermittent surface water flows. Freshwater exploration wells also exist in the western portion of the basin with demonstrated pumping rates that exceed 40 L/s (Hydro Exploraciones, 2020). Furthermore, a conceptual water balance of the basin recharge has been prepared and indicates that the average estimated freshwater recharge in the Laguna Verde Basin corresponds to 570 L/s (M&A, 2024a). Potential sources of freshwater for the Project include the application for groundwater rights in the basin or the purchase of existing water rights from third parties. Under normal conditions, the constitution of water rights may require approximately one year from the date of filing.

The extracted process water at the project area will require treatment with a low-pressure reverse osmosis unit to produce the required quality of demineralized water for eluate washing and other process water requirements.

Figure 8: Identified Water Abstraction Points and Registered Water Rights

 Laguna Verde and Laguna del Negro Francisco Areas

Mining Method

The mine plan is based on a 25-year Life-of-Mine (LOM) with an initial ramp-up followed by steady-state production of 15,000 tpa LCE:

•             Months 1 - 2:                    70% capacity

•             Month 3:                             85% capacity

•             Months 4 - 5:                    90% capacity

•             Month 6 onward:             Full capacity (15,000 tpa LCE)

The modelled average extracted lithium concentration over the LOM is approximately 186 mg/L, with limited dilution over time. Modelled average brine feed rates are:

•             ~524 L/s during Year 1

•             ~568 L/s from Year 2 onward

Wellfield Design

Full-scale production requires 36 vertical production wells, each designed to:

•             Reach a total depth of approximately 400 m

•             Be screened from 200-400 m below surface

•             Target permeable unconsolidated and coarse tuff units

•             Be spaced on average approximately 400 m apart

Placing the top of the screen at a 200 m depth is intended to minimize dilution from shallow freshwater or reinjected brine. Wells are projected to be constructed with 10-inch stainless steel casing and equipped with 8-inch submersible pumps. Brine will be conveyed through HDPE pipelines to a raw brine receiving pond and then to the DLE facility.

Production well locations were selected to remain within Measured and Indicated Resource zones, fall within the CEOL polygon (outside of the exclusion zone) and within CleanTech's preferential licenses, and be located in areas supported by aquifer testing (notably wells LV05 and LV06 which were pump tested).

Figure 9: Well Field Layout

Mineral Resource Assessment and Reserves

The total Measured plus Indicated plus Inferred Resource estimate for the Laguna Verde Project is estimated at 1.90 million tonnes LCE, with an average lithium grade of 174 mg/L. Of this, Measured plus Indicated is 835,000 tonnes LCE at an average lithium grade of 178 mg/L. This resource estimate was completed on October 30 2025 and a detailed announcement was released on November 10, 2025 (Link). For further details on the estimate please refer to this announcement.

The Ore Reserve estimate is derived from the Measured and Indicated Mineral resources and is based on:

-      A calibrated 3D groundwater model (MODFLOW -USG),

-      Variable density flow and transport,

-      25-year production simulation.

-      A 36 well production wellfield

-      Screens set at 200-400 m depth to limit dilution

Ore Reserves are reported at the point of reference of processed brine (rather than from the production wellheads); the lithium mass extracted from the wells was multiplied by a process efficiency factor of 85.5% based on the process plant recovery rate.

All Ore Reserves are classified as Probable.

The Probable Reserve Estimate for the Project corresponds to 378,000 tonnes of LCE at an average grade of 186 mg/L, sufficient to support the ramp-up and subsequent annual output of 15,000 tonnes LCE over the 25-year operating life. A lithium cut-off grade of 100 mg/L was applied to the reserve estimate based on the chosen direct lithium extraction processing method, as well as conservative metrics for long term lithium prices, and capital expenditure and operating expenses.

Table 1: Summary of Resources and Reserves by Category (Resource effective date of 30 October 2025, and Reserve effective date of 09 March 2026)

Permitting and Environmental Considerations

A CEOL is required in Chile to exploit lithium. A decree was issued by the Ministry Mining on 10 March 2026 granting a CEOL to the Company for the Laguna Verde project for 40 years. This decree is, as required for all decrees, undergoing review by the Comptroller General's Office to ensure it complies with the Constitution and laws of Chile following which the CEOL will be signed by the President of Chile and the Company.

The environmental and social assessment is aligned with Chilean regulatory requirements and reflects the Project's development stage at the PFS level. The Project incorporates DLE with reinjection of spent brine, significantly reducing evaporative losses compared to traditional solar evaporation operations with faster production rates and a higher rate of recoveries of lithium with a smaller environmental footprint.

Environmental baseline studies have been initiated and form the foundation for permitting. Key environmental considerations include:

·    Hydrogeological management,

·    Reinjection strategy,

·    Water sourcing,

·    Energy supply,

·    Waste management, and

·    Community engagement.

The Project remains subject to Chilean environmental permitting processes and CEOL regulatory requirements. Permitting remains a critical path item.

The Project will require submission to Chile's Environmental Impact Assessment System ("SEIA") and approval of a Resolution of Environmental Qualification ("RCA") prior to construction. The Project is not located within Sistema Nacional de Áreas Silvestres Protegidas del Estado ("SNASPE") protected areas but lies within a Zone of Tourist Interest ("ZOIT"). Exploration activities have been designed to minimize impacts.

Community Engagement and Social Strategy

There are no communities within the area of influence of the project, however six communities are present along transportation routes CH31 and CH601. The Pastos Grandes, Runa Urka and Sinchi Wayra communities are located on the CH31 route, while the Pai Ote, Copiapó and Sol Naciente communities are present on the CH601 route.

Figure 10: Location of Indigenous Communities

CleanTech Lithium frames lithium development in a manner that is environmentally and socially sound. The Company is committed to a sustainability strategy that positions it as a leader in sustainable lithium development through early participation of indigenous communities and a broad range of stakeholders.

A formal partnership agreement with the nearby indigenous communities, signed in December 2024, supports baseline work and EIA participation through a joint working group. Through this agreement, communities will provide vital local knowledge for baseline studies and contribute directly to the overall EIA process.

The Company's engagement strategy is built on the following principles:

·      Early and participatory consultation

·      Transparent information channels and ongoing dialogue mechanisms

·      Focus on impact management, local employment and investment

·      Commitment to free, prior and informed consultation processes

This approach is evidenced by multiple engagement activities, including organised visits to the DLE pilot plant, drilling campaigns and numerous consultation meetings. The Company's commitment to regional development is further demonstrated by the opening of a community outreach office in Copiapó and an employment and local skills strategy developed in partnership with the Universidad de Atacama. The recent public endorsement by local communities including from Indigenous Community President Ercilia Araya confirms that this is not merely a statement of intent, but a clear path of engagement grounded in cultural and environmental stewardship.

Figure 11: DLE Pilot Plant Inauguration Event with Indigenous Communities and Local Government Representatives, May 2024

The social strategy aims to support long-term community acceptance and shared value development. Early conversations on topics such as protocols, participation, investments, local employment and follow-up of initiatives have enabled the Company to identify areas to foster autonomy and acceptance of the Project.

Project Financials and Economics

Capital Costs

The capital cost estimate has been prepared with an effective date of 1 March 2026. The capital estimate corresponds to an AACE Class 4 level of definition, consistent with a PFS. The expected accuracy range is approximately -30% to +45%, reflecting the current level of engineering maturity. Pricing is based on Q4 2025 US dollar values in constant terms, with no escalation applied.

Mechanical works represent the largest discipline component within direct costs, followed by concrete and structural works. This distribution reflects the process-intensive nature of both the DLE-based LiCl plant and the lithium carbonate conversion facility.  From an area perspective, the Laguna Verde salar site represents the largest share of direct capital expenditure, driven by:

·    The LiCl process plant;

·    Production and reinjection wells;

·    Infrastructure and energy systems;

·    High-altitude construction requirements.

The Copiapó site capital is primarily driven by the lithium carbonate plant and associated reception, storage and services infrastructure.

The base case assumes that the high-voltage transmission line will be delivered under a third-party BOOT arrangement. Accordingly, the capital estimate includes only on-site electrical infrastructure and connection facilities.

Capital Cost Summary:

The PFS includes a detailed analysis of the direct and indirect costs based on a CAPEX Report prepared by the study integrator. Key third-party and client-supplied inputs incorporated into the estimate include:

·    The Laguna Verde LiCl plant and the Copiapó Li₂CO₃ plant, designed and budget-priced by Lanshen;

·    Main buildings at both sites, costed by ISM Ingeniería (including prefabricated structures and civil works);

·    36 production wells and associated booster pumps, costed by CTL based on a budgeted quotation provided by Geotec Boyles SA, a company based in Santiago, Chile;

·    Brine pumping and transport infrastructure (civil, electrical systems, transmission lines and pipelines), engineered by Agora Soluciones.

The capital estimate reports a Total Installed Cost (TIC) of approximately US$748.2 million, including owner's costs and contingency.  Capital costs are shown by project area and Work Breakdown Structure (WBS) is provided in Table 2, distinguishing between the Salar site and the Copiapó site:

Table 2: Project Cost Estimate Summary by Area

Direct costs total approximately US$474.5 million, representing approximately 63% of TIC. Indirect costs total approximately US$129.6 million, reflecting execution strategy, high-altitude logistics and temporary facilities requirements. Owner's costs total approximately US$19.0 million (approximately 3% of TIC), and contingency totals approximately US$125.1 million, representing approximately 17% of TIC and approximately 20% of the base estimate.

Indirect Costs, Owner's Costs and Contingency:

·    Indirect costs: (approximately US$129.6 million) include engineering, procurement and construction management (EP/CM), temporary facilities, a 600-bed construction camp, freight and duties, spares and first-fill items (including adsorbents, resins and membranes), third-party engineering services, vendor representatives and commissioning support.

·    Owner's costs: (approximately US$19.0 million) are estimated at approximately 4% of direct costs and include project management support functions and allowances for permitting, EIA preparation and community engagement.

·    Contingency: (approximately US$125.1 million) has been included to address uncertainties inherent at PFS level, including design maturity, quantity variability, productivity assumptions, logistics and high-altitude construction risk. Contingency excludes scope changes and force majeure costs.

The following Figure 12 shows the capex profile of the project, including first fill and sustaining capex:

Figure 12: Capital Expenditures and Timing

Capex Cost Intensity:

The capex costs of US$748m equates to a capex intensity of approximately US$49,900 per tonne of battery grade lithium carbonate which compares favourably with other DLE projects in development globally. The Company will look to further optimise the project capex during the DFS stage and is considering various technical options which could improve efficiencies in the overall DLE process. 

Key Qualifications and Exclusions:

Exclusions from the estimate include escalation, financing costs, foreign exchange impacts, closure and rehabilitation costs, ramp-up operating losses, sustaining capital and environmental or community expenditures beyond the defined owner's allowance.

Sustaining Capex:

Sustaining capex is required after the initial project investment to maintain ongoing operations. Sustaining capital for the Project primarily comprises the first fill of consumable process materials supplied by Lanshen, including adsorbents, resins, and membranes.  The sustaining capital costs for adsorbents and resins, which are required to commission and operate the facilities, total US$42.83 million.

Ongoing sustaining capex is required throughout the remaining 24-year life of the project, amounting to an average of approximately US$9 million per annum, although costs vary year on year, depending on facility requirements.

Operating Costs

The operating cost estimate has been prepared at PFS level, primarily based on an OPEX Report prepared as part of the study. The estimate integrates process definitions, mass balances, and reagent and consumable consumption data provided by CTL and Lanshen, combined with Worley's cost databases and prevailing Chilean and international pricing for labour, energy, reagents, consumables and logistics.

The operating model assumes steady-state production of 15,000 tpa of battery-grade Li₂CO₃, with continuous operation across both the Laguna Verde salar facilities and the Copiapó lithium carbonate plant. The basis assumes approximately 8,000 operating hours per year.

The estimate excludes escalation, financing costs, corporate overhead beyond the Project General Manager level, technology licensing fees, and government royalties (which are incorporated separately in the economic model).

Operating Cost Structure:

Operating costs are classified into direct and indirect components, consistent with Worley's PFS methodology. The total operating cost combines Laguna Verde and Copiapó direct costs plus local G&A.

·    Total production cost: US$ 5,768/t Li₂CO₃ (approximately US$ 86.516 million per year)

Table 3: Project Total OPEX - 15,000 tpa Li₂CO₃

Indirect operating costs include General and administrative (G&A) expenses, Insurance, communications and security, personnel transport between urban centres and operating sites.

Economic Analysis

The economic evaluation for the Laguna Verde Project PFS was completed in accordance with JORC and written to be consistent with the disclosure requirements of NI 43-101, with an effective date of March 1, 2026. The evaluation was based on a discounted cash flow (DCF) model prepared for the study that integrated the CAPEX and OPEX estimates, a production schedule constrained by hydrogeology and process design (Montgomery & Associates and Lanshen inputs), and long-term lithium carbonate pricing assumptions from Canaccord Genuity (Nov 2025). The model produces annual cash flows and calculates NPV, IRR, and payback on both a before-tax and after-tax basis.

Evaluation Criteria:

The analysis evaluates an approximately two-year construction period followed by 25 years of operations. Results are stated in real (constant dollar) 2026 US dollars with no inflation escalation applied to costs or revenues. Cash flows are discounted at an 8% real discount rate, and NPVs are calculated as of the start of construction in 2029 (cash flows discounted to this 2029 date).

Cashflow & Economic Analysis: 

The economic analysis carried out in the study included the following basic assumptions:

Table 4: Key Assumptions in Economic Analysis of Laguna Verde project

Revenues: 

Based on annual production of 15,000 tpa LCE:

Table 5: Production Revenues

Cash Flow Projection:

The cash flow forecast integrates capital expenditures, operating costs, revenues, taxes, royalties, CEOL-related payments, depreciation, amortization, and working capital movements to generate annual before-tax and after-tax cash flows.

The resulting Project cash flow projection forms the basis for the calculation of economic indicators, including NPV, IRR, and payback period:  

Annual cashflows are strong throughout the life of the project as shown in Figure 13 below:

Figure 13: Project Annual Cash Flows - 15,000 tpa Li₂CO₃

Figure 14: Cumulative Cash Flows - 15,000 tpa Li₂CO₃

During steady-state operations, annual royalty payments are approximately US$18 million. Based on an assumed production rate of 15,000 tpa of lithium carbonate and a lithium sales price of US$22,500 per metric tonne, the combined weighted average royalty burden over the evaluation period is estimated at approximately 6.1% of gross revenues.

Economic Evaluation Results:

Based on the assumptions described above, the Laguna Verde Project demonstrates strong economic performance. On a before-tax basis, the project generates an NPV (8%) of approximately US$ 1.37 billion, with an IRR of approximately 24.2% and a payback period of approximately 3.9 years from commencement of commercial production.

On an after-tax basis, the project generates an NPV (8%) of approximately US$0.96 billion, with an IRR of approximately 21.2% and a payback period of approximately 4.0 years.

Table 6: Summary of Economic Results

 Sensitivity Analysis:

A post-tax sensitivity analysis evaluates the effect of varying CAPEX, lithium carbonate price, production rate, and OPEX independently to 80%, 90%, 110%, and 120% of base case, measuring impacts on NPV (8%) and IRR. The results show NPV is most sensitive to price, followed by production, while CAPEX and OPEX have comparatively smaller impacts on NPV within the tested ranges. Similar results are obtained for the IRR sensitivity.

Table 7: Project After Taxes - NPV 8% Sensitivity

Figure 15: Project After Taxes NPV 8% Sensitivity

The results indicate that, as expected, the project's NPV is highly sensitive to lithium carbonate price levels. A ±20% variation in lithium carbonate price results in an approximate 42% change in NPV, making price the most influential driver on project value.

The project is also materially sensitive to production levels, with a ±20% variation in production rate resulting in an approximate 33% change in NPV. This reflects the strong leverage of production throughput on revenue generation and overall project economics.

By comparison, the project's NPV is less sensitive to variations in CAPEX and OPEX. A ±20% variation in CAPEX results in an approximate 12% change in NPV, while a ±20% variation in OPEX leads to an approximate 11% change in NPV. This reflects the relative scale of operating margins and long-term revenue generation compared to upfront and ongoing cost variations.

The economic results are based on preliminary engineering and economic assessments and are subject to risks and uncertainties, including lithium price variability, process performance, permitting outcomes and project execution.

The PFS is based on preliminary engineering and economic assessments and incorporates information provided by CleanTech Lithium PLC and third-party consultants. While Worley has acted as study integrator and provided engineering and cost estimation services, it has not independently verified all third-party inputs and does not accept responsibility for such information. The results presented are subject to risks and uncertainties typical of projects at this stage of development.

Funding the Development

CleanTech Lithium announced in early January 2026 that it had appointed Cutfield Freeman & Company Limited ("Cutfield") as its Financial Advisor for the purposes of supporting the Company in selecting a strategic partner for the next phase of development at the Laguna Verde project and in structuring the financing pathway towards commercial production.

The Company has been working closely with Cutfield since their appointment and they are confident the economics of PFS are sufficiently robust to elicit real interest from the many parties of scale they have on the target list agreed with the Company, including relevant supporting banks.  This includes OEMs, international traders, battery manufacturers, industry players and other entities. This is in addition to parties the Company has had under NDA for some time and who have been awaiting the approval of the CEOL and release of the PFS.   

Cutfield will now commence their process to select a strategic partner. The CTL Board believes that Laguna Verde will be a very attractive project for parties looking to secure long-term lithium carbonate supply at a time where demand is forecast to increase substantially in the coming years and supply becomes increasingly constrained.   

Competent Persons Statement

The following professionals act as competent persons, as defined in the AIM Note for Mining, Oil and Gas Companies (June 2009) and JORC Code (2012):

Mr. Michael Rosko is a Registered Member of the Society for Mining, Metallurgy and Exploration, member #4064687. He graduated from the University of Illinois with a bachelor's degree in geosciences in 1983, and from the University of Arizona with a master's degree in geosciences in 1986. Mr. Rosko is a registered professional geologist in the states of Arizona (#25065), California (#5236), and Texas (#6359). Mr. Rosko has practiced his profession for 40 years and has been directly involved in design of numerous exploration and production well programs in salar basins in support of lithium exploration, and estimation of the lithium resources and reserves for many other lithium projects in Argentina and Chile. Mr. Rosko is a Vice President and Senior Hydrogeologist at Montgomery & Associates.

Mr. Brandon Schneider is employed as a Senior Hydrogeologist at Montgomery & Associates. He graduated from California Lutheran University in 2011 with a Bachelor of Science degree in Geology (with Honors) and obtained a Master of Science in Geological Sciences (Hydrogeology focus) from the University of Notre Dame in 2013. He is a professional in the discipline of Hydrogeology, and is a Registered Professional Geologist in Arizona (#61267) and SME Registered Member (#4306449). He has practiced his profession continuously since 2013. His relevant experience includes: (i) from 2013 to 2016, consulting hydrogeologist specializing in hydrogeological characterizations, aquifer test analyses, groundwater modeling, and pumping well optimization for mining projects and sedimentary basins in Arizona, United States; (ii) since 2017, consulting hydrogeologist in Chile specializing in lithium brine projects in Argentina and Chile with relevant and continuous experience in brine exploration, lithium brine resource and reserve estimates, resource and reserve reporting, variable density flow and transport modeling, and optimization of groundwater pumping.

Mr. Marcelo Bravo, Chemical Engineer (Universidad Católica del Norte), has a Master's Degree in Engineering Sciences major in Mineral Processing, Universidad de Antofagasta. He currently works as a Senior Process Consulting Engineer at the Ad-Infinitum company. Mr Bravo has relevant experience in researching and developing potassium, lithium carbonate, and solar evapo-concentration design processes in Chile, Argentina, and Bolivia. Mr Bravo, who has reviewed and approved the information contained in the chapters relevant to his expertise contained in this announcement, is registered with No. 412 in the public registry of Competent Persons in Mining Resources and Reserves per the Law of Persons Competent and its Regulations in force in Chile. Mr Bravo has sufficient experience relevant to the metallurgical tests and the type of subsequent processing of the extracted brines under consideration and to the activity being carried out to qualify as a competent person, as defined in the JORC Code. Mr Bravo consents to the inclusion in the press release of the matters based on his information in the form and context in which it appears.

Tables included in this RNS have been sourced directly from the PFS or are based on data that is from the PFS.

Investors can sign up to Investor Meet Company for free and add to meet CleanTech Lithium Plc via: https://www.investormeetcompany.com/cleantech-lithium-plc/register-investor

Beaumont Cornish Limited ("Beaumont Cornish") is the Company's Nominated Adviser and is authorised and regulated by the FCA. Beaumont Cornish's responsibilities as the Company's Nominated Adviser, including a responsibility to advise and guide the Company on its responsibilities under the AIM Rules for Companies and AIM Rules for Nominated Advisers, are owed solely to the London Stock Exchange. Beaumont Cornish is not acting for and will not be responsible to any other persons for providing protections afforded to customers of Beaumont Cornish nor for advising them in relation to the proposed arrangements described in this announcement or any matter referred to in it.

Glossary

Notes

CleanTech Lithium (AIM:CTL, Frankfurt:T2N) is an exploration and development company advancing lithium projects in Chile for the clean energy transition. CleanTech Lithium has two key lithium projects in Chile, Laguna Verde and Viento Andino, and exploration stage project in Arenas Blancas (Salar de Atacama), located in the lithium triangle, a leading centre for battery grade lithium production. CleanTech Lithium and the Mining Ministry in Chile have agreed the contractual terms for the Special Lithium Operating Contract ("CEOL") for Laguna Verde, subject to final ratification.

CleanTech Lithium is committed to utilising Direct Lithium Extraction ("DLE") with reinjection of spent brine. Direct Lithium Extraction is a transformative technology which removes lithium from brine with higher recoveries, short development lead times and no extensive evaporation pond construction. For more information, please visit: www.ctlithium.com

**ENDS**

JORC Code, 2012 Edition - Table 1

Section 1 Sampling Techniques and Data

(Criteria in this section apply to all succeeding sections.)

Section 2 Reporting of Exploration Results

(Criteria listed in the preceding section also apply to this section.)

Section 3 Estimation and Reporting of Mineral Resources

(Criteria listed in section 1, and where relevant in section 2, also apply to this section.)

Section 4 Estimation and Reporting of Ore Reserves

(Criteria listed in section 1, and where relevant in sections 2 and 3, also apply to this section.)