| Geothermal Resource Type | Hydrothermal, enhanced geothermal systems, geothermal heat-pump wells, or high-temperature systems above approximately 150°C. | A technical proposal identifying the reservoir type, temperature range, target depth, expected pressure, and well purpose. | Well design, drilling equipment, materials, testing methods, and cost can differ substantially by resource type. |
| Target Well Depth | Many commercial geothermal wells are approximately 1,000–5,000 m deep; enhanced geothermal projects may require roughly 3,000–6,000 m or more. | Depth capability of the proposed rig, drilling plan, casing program, and previous project depth records. | Greater depth generally increases drilling time, temperature exposure, equipment requirements, and project risk. |
| Formation Temperature | Low-temperature applications commonly operate below 90°C; direct-use and power projects often target approximately 90–150°C or higher, depending on technology. | Temperature logging method, maximum tool rating, expected bottom-hole temperature, and thermal-cycling procedures. | Temperature affects cement selection, casing design, logging tools, pumps, seals, and power-conversion efficiency. |
| Expected Flow Capacity | Commercial production rates vary widely by reservoir; project screening should normally compare the supplier’s guaranteed test method rather than a generic flow-rate claim. | Well-test program covering injectivity, productivity, pressure drawdown, recovery, fluid chemistry, and measurement uncertainty. | A reliable test plan is more meaningful than an advertised flow rate because geothermal wells are highly site-dependent. |
| Drilling Method and Rig Capacity | Rotary drilling is widely used; deeper or harder formations may require high-torque rigs, air or foam drilling, directional drilling, and specialized bottom-hole assemblies. | Rig specifications for depth, hook load, rotary torque, pump pressure, blowout-control equipment, and directional capability. | The rig must match the formation, trajectory, pressure regime, and planned casing sizes. |
| Casing and Wellhead Materials | Casing and wellhead components should be selected for anticipated temperature, pressure, corrosion, scaling, and thermal expansion conditions. | Material grades, connection specifications, pressure ratings, corrosion allowance, inspection records, and applicable API or ISO documentation. | Hot brines, dissolved gases, chlorides, and repeated heating and cooling can reduce component service life. |
| Cementing and Zonal Isolation | The design should address high temperature, lost circulation, thermal expansion, permeability, and isolation between aquifers or production zones. | Cement formulation, laboratory test results, centralizer plan, bond-log procedure, pressure-test criteria, and remedial-cementing capability. | Poor zonal isolation can cause cross-flow, contamination, casing damage, and expensive workovers. |
| Well Testing and Logging | A complete program may include temperature, pressure, caliper, cement-bond, spinner, acoustic, resistivity, injectivity, and production testing as appropriate. | Calibration certificates, tool temperature and pressure ratings, sample reports, data formats, and interpretation deliverables. | Independent data helps confirm reservoir performance and supports financing, permitting, and plant design. |
| High-Temperature Equipment | Tools, pumps, seals, cables, mud systems, and well-control equipment should be rated above the project’s expected operating temperature and pressure. | Equipment datasheets, maximum operating limits, maintenance intervals, spare-parts plan, and contingency procedures. | Temperature-related equipment failure is a major source of nonproductive time in deep geothermal drilling. |
| Fluid Chemistry Management | The design should consider silica scaling, carbonate scaling, corrosion, salinity, non-condensable gases, and potentially hazardous constituents such as hydrogen sulfide. | Sampling plan, laboratory analysis, corrosion and scaling model, chemical-treatment options, and worker-exposure controls. | Fluid chemistry affects flow assurance, materials selection, environmental compliance, and operating cost. |
| Health, Safety, and Well Control | The supplier should maintain formal well-control, pressure-control, H₂S-response, confined-space, lifting, emergency, and site-traffic procedures. | Safety-management certification, training records, incident statistics, emergency-response plan, and well-control certification of key personnel. | Geothermal operations can involve high pressure, hot fluids, toxic gases, heavy equipment, and unstable formations. |
| Standards and Quality Control | Procurement should specify applicable API, ISO, ASTM, local regulatory, and project-specific engineering requirements rather than relying on a general quality statement. | Quality manual, inspection and test plan, nonconformance process, traceability records, calibration certificates, and third-party inspection options. | Documented quality controls reduce failures, disputes, rework, and difficulties with regulators or insurers. |
| Environmental Performance | The project should include closed-loop fluid handling where appropriate, drilling-fluid control, cuttings management, water protection, noise control, and well-abandonment planning. | Environmental management plan, waste-disposal records, spill-response procedure, emissions controls, and restoration obligations. | Environmental requirements vary by jurisdiction and can determine whether permits and community approvals are obtained. |
| Project Schedule and Delivery | The schedule should separate engineering, permitting, mobilization, drilling, completion, testing, demobilization, and contingency time. | Detailed baseline schedule, critical-path analysis, equipment-mobilization plan, long-lead-item list, and delay-notification procedure. | Remote locations, customs, weather, road access, and specialist equipment can materially affect delivery time. |
| International Logistics | The supplier should be able to manage export documentation, customs classification, transport permits, local-content rules, and country-specific import requirements. | Incoterms, shipping plan, packing standards, customs responsibilities, insurance coverage, and local service-partner arrangements. | Clear logistics responsibility helps prevent border delays, unexpected charges, and equipment shortages. |
| Commercial Transparency | A comparable bid should distinguish mobilization, drilling-meter rates, casing, cementing, logging, testing, standby, consumables, taxes, freight, and contingency allowances. | Itemized quotation, assumptions, exclusions, escalation terms, currency, payment milestones, performance guarantees, and change-order rules. | A low headline price may exclude major services or site risks and therefore may not represent the lowest total project cost. |
| After-Sales and Local Support | Support should cover commissioning, troubleshooting, operator training, spare parts, warranty response, data handover, and workover planning. | Service-level agreement, response times, regional technicians, spare-parts inventory, warranty terms, and training curriculum. | Local support can reduce downtime and improve long-term well availability after drilling is complete. |
| Supplier Evaluation Score | A practical weighted model may assign 25% to technical capability, 20% to safety and quality, 20% to total cost, 15% to schedule, 10% to logistics, and 10% to service support. | Completed bid-comparison matrix with pass/fail requirements, weighted scores, documented assumptions, and reference checks. | A transparent scoring method helps global buyers compare suppliers consistently without relying only on price or marketing claims. |
