Luna 12 Tidal Kite Turbine System

An underwater kite system that flies in figure-of-eight trajectories through tidal streams to generate renewable electricity from ocean currents. Designed by Minesto with SKF-engineered components, the system operates tethered to the seabed and converts kinetic energy from water—830 times denser than air—into 9,500 kWh average daily output, sufficient to power 200 Faroese homes annually. Critical components include the rudder, turbine, and generator optimized for minimal friction and maximum energy conversion in deep-ocean conditions.

complexity: hardtolerance: high precision
Luna 12 Tidal Kite Turbine System

Snapshot

Feasibility at a glance

PT localization

4/10

Partial

Only finishing and testing can be localised in Portugal.

Per unit

€500,000–€2,000,000

at 1-unit volume

Starter batch

1units

minimum viable run

To first batch

78weeks

8 phases, design to ship

Budget

€85,000–€140,000 for 90-day foundation phase

all-in estimate

Bottom line

Tidal energy systems occupy a rare intersection of aerospace-grade composites, naval architecture, and power electronics where domain expertise and marine certification trump cost considerations. The SKF bearing specification signals that sub-suppliers must meet subsea reliability standards; co-development with proven EU marine energy partners (e.g., composite fabricators serving offshore wind, naval-certified power electronics firms) is the only viable path to a deployable, insurable, and certifiable system within reasonable timelines.
Read full insight

A tidal kite turbine system requires deep marine engineering expertise, precision composite fabrication, and subsea-rated electrical systems that no Portuguese manufacturer currently possesses. Co-development with established EU marine energy partners—such as composite specialists, bearing suppliers like SKF, and offshore system integrators—provides access to proven subsea technology, certification pathways (including marine classification societies), and field deployment experience in North Atlantic conditions. While white-label options do not exist for such specialized equipment, and local production lacks the necessary domain knowledge and supply chains for marine-grade magnets, seals, and pressure-rated housings, an EU partnership leverages existing tidal energy programs (Scotland, France, Netherlands) and shared R&D funding. China offers cost savings but introduces critical IP risks for proprietary hydrodynamic designs and exposes the project to complex dual-use export controls on subsea technology.

What it does

4 capabilities

Converts tidal stream energy into renewable electricity by flying underwater like a kite

Generates an average of 9,500 kilowatt-hours per day to power approximately 200 homes year-round

Operates predictably by following the moon's gravitational cycle that drives ocean tides

Maximizes energy capture by flying at speeds several times faster than the actual water current

How it's made

5 stations · build route

  1. 1

    Composite kite wing fabrication

    Carbon fiber and epoxy are laid up in molds to create the hydrodynamic wing structure that withstands deep-sea forces.

  2. 2

    Precision bearing and shaft machining

    SKF engineers marine-grade bearings and CNC-machines shafts for the rudder, turbine, and generator with minimal friction tolerances.

  3. 3

    Generator winding and magnet assembly

    Copper coils are wound around stators and neodymium magnets installed to convert mechanical rotation into electrical power.

  4. 4

    Subsea integration and sealing

    All mechanical and electrical components are assembled into sealed housings rated for deep-ocean pressure and saltwater corrosion.

  5. 5

    Tidal stream testing and commissioning

    The complete system is deployed offshore, tethered to the seabed, and tested through full tidal cycles to validate power output.

Risks to watch

5 identified · 3 blocking

1 critical
2 high
2 medium

Critical

Intellectual Property Exposure in Hydrodynamic Design

The kite's figure-of-eight flight control algorithms, wing hydrodynamics, and turbine blade profiles represent core competitive IP. Sharing CAD models and control system specifications with offshore manufacturers—especially in jurisdictions with weak IP enforcement—risks reverse engineering and direct competition in the emerging tidal energy market. Chinese manufacturers have documented history of copying marine technology (e.g., offshore wind turbine designs), and legal recourse is limited and expensive. Loss of IP advantage would undermine the business model and investor confidence, particularly if competitors enter the same tidal sites with cloned technology.

Mitigation — Structure co-development agreements with strict EU-jurisdiction governing law and binding arbitration clauses. Partition IP by subsystem: release only interface specifications (mounting points, power output curves, pressure ratings) to sub-suppliers, retaining flight control software, blade geometry, and hydrodynamic modeling in-house or with trusted Tier-1 partners under NDA and escrow arrangements. Use watermarking and geometric fingerprinting in CAD files to trace leaks. Physically separate final integration, control system programming, and sea trials to EU facilities where proprietary tuning and calibration occur. File defensive patents in key markets (EU, US, China, Japan) before engaging manufacturers.

High

Neodymium Magnet Supply Chain Concentration

Neodymium magnets for the generator assembly depend on rare-earth elements where China controls >80% of global refining capacity. Supply disruptions, export quotas, or geopolitical tensions could halt production or spike costs unpredictably. EU sources exist (e.g., Vacuumschmelze in Germany, Less Common Metals in UK) but at 40–60% cost premiums and longer lead times. Without secured magnet supply agreements, the entire generator assembly timeline is at risk, and performance de-rating (switching to ferrite magnets) would significantly reduce power output and economic viability.

Mitigation — Establish dual-source agreements: primary supply from EU-based rare-earth processors (Vacuumschmelze, Solvay rare-earth division) with contractual volume commitments, and secondary contingency through North American suppliers (USA Rare Earth, MP Materials). Negotiate 12-month forward pricing contracts to hedge against volatility. Design the generator with modular magnet cassettes to allow rapid supplier switching without redesigning the entire rotor assembly. Allocate 15% cost contingency for magnet procurement and maintain 6-month strategic inventory once production starts.

High

Marine Classification and Grid Connection Delays

Tidal energy systems require certification from marine classification societies (DNV, Lloyd's Register, Bureau Veritas) for seaworthiness, plus grid connection approvals from transmission system operators (TSOs). The process involves design reviews, witness testing of pressure housings and seals, fatigue analysis of composite structures, and offshore commissioning inspections—all of which can extend 12–18 months. Any design changes during testing restart portions of the certification cycle. Without certification, the system cannot be insured, financed, or connected to national grids, rendering it commercially useless despite technical functionality.

Mitigation — Engage a marine classification society (DNV-GL recommended for tidal energy experience) at the preliminary design phase to align specifications with certification standards before fabrication begins. Use pre-certified components where possible (SKF bearings with subsea service history, pressure housings with existing approvals for similar depth ratings). Build certification milestones into the project timeline with 20% schedule buffer. Conduct pre-certification testing (pressure cycling, salt spray, vibration) in accredited EU labs to identify issues early. Assign a dedicated certification manager to liaise with the society and TSO, ensuring documentation and witness test scheduling proceed in parallel with manufacturing rather than sequentially.

Medium

Composite Tooling and Cure Cycle Bottlenecks

The carbon fiber wing structure requires custom molds (tooling) that take 12–16 weeks to machine and validate, followed by layup and autoclave cure cycles that can only process one or two units per week depending on part size. Composite suppliers (Gurit, Sicomin, Hexcel) often have 8–12 week lead times for prepreg materials in specialized marine-grade resins. Any design iteration that changes wing geometry forces tooling rework, adding 10–14 weeks. Bottlenecks in autoclave capacity (shared with aerospace and defense customers) can further delay delivery, especially in Q4 when aerospace demand peaks.

Mitigation — Freeze the wing geometry CAD as early as possible and validate hydrodynamics via CFD and scale-model testing before committing to full-size tooling. Order prepreg materials and schedule autoclave slots immediately upon design sign-off, even before tooling completion. Negotiate priority access agreements with composite fabricators by offering volume commitments or co-investment in dedicated tooling. Design the wing with modular sections (if feasible) to parallelize production across multiple molds and reduce single-part cure time. Maintain close communication with the fabricator's production scheduler to anticipate capacity constraints and adjust timelines proactively.

Medium

Offshore Testing Weather Windows and Logistics

Final commissioning requires deploying the tidal kite in open water during suitable weather and tidal conditions. North Atlantic sea states limit safe deployment windows to ~150 days per year, typically spring and summer. Mobilizing support vessels, divers, ROVs, and installation crews costs €15,000–€30,000 per day; delays due to weather can consume contingency budgets rapidly. If initial deployment reveals performance issues (e.g., turbine cavitation, control instability, cable chafing), retrieval, modification, and redeployment add 6–12 weeks. Grid connection and power quality testing add further sea-time requirements.

Mitigation — Conduct extensive onshore and tank testing (tow-tank facilities, pressure chambers, benchtop turbine dynamometers) to validate subsystems before offshore deployment. Schedule first deployment early in the spring weather window with 4-week buffer before summer storm season. Pre-position support vessels and equipment through framework contracts with offshore wind service providers who already operate in target tidal zones. Use ROVs with real-time telemetry to monitor performance during initial runs, allowing rapid diagnosis without full retrieval. Design the system with quick-release tether mechanisms and modular subsea connectors to minimize vessel time per deployment cycle. Build a second prototype in parallel so engineering changes don't stall the entire program.

Production timeline

78 weeks to first batch

wk 1wk 78

Hydrodynamic Design Finalization and CAD Freeze

wk 1–14

Composite Tooling Fabrication and Material Procurement

wk 15–30

Wing and Rudder Composite Layup and Curing

wk 31–40

Turbine and Generator Assembly

wk 41–52

Control System Integration and Pressure Testing

wk 53–60

System Integration and Onshore Testing

wk 61–66

Marine Classification Witness Testing and Certification

wk 67–72

Offshore Deployment and Commissioning

wk 73–78

wk 15–30 is the longest stretch — Composite Tooling Fabrication and Material Procurement takes 16 weeks of the 78 weeks on this build.

What goes into it

6 materials · 8 processes

Materials

carbon_fiber_compositestainless_steel_marine_gradecopper_windingsepoxy_resinneodymium_magnetspolyurethane_seals

Processes

composite_layupcnc_machiningmotor_windingsheet_metalweldingfinal_assemblytesting_inspectioncable_assembly

Design philosophy and best practices

5 principles

A tidal kite turbine flies a wing on a tether through tidal current so the turbine moves faster than the water. It must survive fatigue, corrosion and fouling for years with little maintenance.

1

Design for fatigue, not just peak load

The wing, tether and anchor see millions of load cycles as the kite flies figure-eight paths. Fatigue data for composites and steel set the design life.

2

Protect against seawater

Use marine-grade materials, coatings and cathodic protection, and seal the generator and electronics to IP68 or better.

3

Plan for fouling

Marine growth adds drag and weight. Antifouling coatings and inspection intervals must be in the budget.

4

Make retrieval easy

Maintenance at sea is costly. Design so the kite can be detached and lifted to a vessel quickly at slack tide.

5

Follow marine energy standards

IEC TS 62600 series and DNV classification rules guide structural, electrical and mooring design.

Common pitfalls

Avoid

Underestimating tether wear at the anchor and kite connection points.

Avoid

Using bearings and seals not rated for submerged long-term service.

Avoid

Ignoring the impact on marine life and the permitting time it takes.

Avoid

Testing only in steady flow and not in turbulent real tidal sites.

10-year evolution forecast (2026-2036)

4 phases

Tidal energy is at the demonstration and early commercial stage. The trends below are sector directions, not forecasts for any company.

2026–2028

Array demonstrations

Trend: small arrays at test sites gather reliability data and cut cost per unit.

2028–2031

Low-flow sites

Trend: kite designs target slower tidal and ocean currents that fixed turbines cannot use well.

2031–2034

Grid and hybrid use

Trend: tidal power is paired with offshore wind and storage for predictable supply.

2034–2036

Industrial supply chains

Trend: serial production of wings and generators emerges if demonstration results hold.

Outlook

Expect tidal kites to move from single units to small arrays, with reliability and maintenance cost deciding commercial success.

Materials intelligence

9 materials

Carbon fibre composites

Medium supply risk

Wing structure

Sourced from: Carbon fibre is made mainly in Japan, the US, the EU and China.

Glass fibre composites

Low supply risk

Rudder and fairings

Sourced from: Produced widely in Europe and Asia.

Epoxy resins

Low supply risk

Composite matrix

Sourced from: Made by chemical firms in the EU, US and Asia.

Duplex stainless steel

Medium supply risk

Fittings and anchor hardware

Sourced from: Nickel and chromium come from Indonesia, South Africa and others; steelmaking is widespread in Europe.

Ultra-high molecular weight polyethylene fibre

Medium supply risk

Tether

Sourced from: Produced mainly in the Netherlands, the US and China.

Copper

Medium supply risk

Wiring, windings and PCB traces

Sourced from: Mined mainly in Chile, Peru and DR Congo; refined widely, including in the EU. Portugal mines copper at Neves-Corvo.

NdFeB magnets

High supply risk

Permanent magnet generator

Sourced from: China dominates rare earth processing and magnet production.

Bearing steel

Low supply risk

Turbine and pivot bearings

Sourced from: Produced in Sweden, Germany, Japan and China.

Marine antifouling coatings

Low supply risk

Surface protection

Sourced from: Made by coatings firms in Europe and Asia.

Biocide use is regulated under the EU Biocidal Products Regulation.

Prototyping and rapid manufacturing in Portugal

5 companies from the atlas

Beyond Composite

Canelas / V.N. Gaia

Composite structures

Carbon fibre wing and rudder prototypes.

Ship repair, machining and welding

Marine-grade steel parts, anchor hardware and sea trials support.

EFACEC

Matosinhos

Electrical equipment and power systems

Generator integration and control system enclosure.

Cabelte

Lousado, Vila Nova de Famalicão

Power and data cables

Subsea power cable for export to shore.

CNC machining, sheet metal and welding

Machined bearing housings and rudder fittings.

591 Portuguese manufacturers matched

None cover the whole build — it splits across steps.