Executive Summary
Emissions from ships at berth—auxiliary engines running to power hotel loads, pumps, and cargo handling—are a concentrated air-quality issue in many ports. Cold ironing, or shore power, replaces on-board generation with grid or low-carbon electricity. For port authorities and terminal operators, the strategic question is no longer whether shore power will be required, but which berths to prioritize, how to structure tariffs, and how to share costs with shipping lines. At Energy Solutions, we benchmark real projects across container, Ro-Ro, and cruise terminals to quantify economics.
- Typical shore power systems for large container ships require 6–12 MVA connection capacity per berth, while modern cruise ships can demand 10–16 MVA depending on climate and vessel size.
- Across our dataset, replacing auxiliary fuel at berth with grid power reduces CO₂ emissions by 40–80% depending on grid mix and typically cuts local NOₓ and PM emissions by >90%.
- From a terminal perspective, well-utilized shore power investments can achieve simple paybacks of 6–11 years, but under-utilized berths or low electricity-to-fuel price spreads push payback beyond 15 years.
- By 2035, Energy Solutions expects shore power to be mandated for most calls in major OECD ports, with differentiated berthing or tariff regimes penalizing non-equipped vessels.
What You'll Learn
- Cold Ironing Basics and Load Profiles at Berth
- Benchmarks: Container, Ro-Ro, and Cruise Shore Loads
- Grid Connection, Infrastructure, and Standards
- Economics: CAPEX, Tariffs, and Payback
- Case Studies: Northern Europe, US West Coast, and Asia
- Global Perspective and Regulatory Drivers
- Devil's Advocate: Utilization, Grid Impacts, and Fair Cost Sharing
- Outlook to 2030/2035: Integrated Port Electrification Roadmaps
- Step-by-Step Guide for Port Authorities and Terminals
- FAQ: Shore Power and Cold Ironing
Cold Ironing Basics and Load Profiles at Berth
Cold ironing—also termed onshore power supply (OPS) or alternative maritime power (AMP)—involves connecting a vessel at berth to shore-side electricity so that auxiliary engines can be shut down. Typical systems step down medium-voltage grid connections (e.g., 11–33 kV) to ship-compatible voltages (commonly 6.6 or 11 kV) using high-capacity transformers and frequency converters where necessary.
Methodology Note
Energy Solutions compiled and normalized data from >40 terminals offering shore power in 2024–2025, covering container, Ro-Ro, cruise, and mixed-use berths. Power demand is expressed as both instantaneous MW and kWh per call, while financial metrics are shown as simple payback and equity IRR ranges. Fuel costs are based on low-sulphur marine gas oil (MGO) or LNG auxiliary use, and grid prices reflect port-specific tariffs.
Benchmarks: Container, Ro-Ro, and Cruise Shore Loads
Representative Electric Loads for Ships at Berth (Typical, 2025)
| Ship Type | Berth Duration (h) | Typical Shore Power (MW) | Energy per Call (MWh) | Notes |
|---|---|---|---|---|
| Container (8–14k TEU) | 12–18 | 4–8 | 60–90 | Reefer load, cranes, hotel loads |
| Container (14–22k TEU) | 16–24 | 8–12 | 110–180 | Higher reefer and auxiliary loads |
| Ro-Ro / Vehicle Carrier | 8–14 | 2–5 | 20–45 | Ramps, lighting, HVAC |
| Cruise Ship (3–5k pax) | 8–12 | 7–12 | 70–110 | Hotel loads dominate, strongly climate-dependent |
Typical Shore Power Demand by Ship Type
Grid Connection, Infrastructure, and Standards
Shore power requires high-capacity grid connections, often at medium or high voltage, with sufficient short-circuit strength and transformer capacity to handle coincident ship loads. IEC/ISO/IEEE 80005 standards define safety, voltage, frequency, and plug-interface requirements for high-voltage shore connections.
Indicative Infrastructure Requirements for a Two-Berth Container Terminal
| Component | Typical Specification | CAPEX Range (2025, EUR) | Key Drivers |
|---|---|---|---|
| Grid connection / substation upgrade | 30–50 MVA at 33 kV | 8–18 million | Existing capacity, cable route, redundancy |
| Frequency converters & transformers | 2 × 10–15 MVA 50/60 Hz units | 12–20 million | Redundancy, vendor, building vs containerized |
| Cable management systems | Automated reel or crane-based systems | 4–8 million | Berth layout, reach, automation |
| Protection, control, civil works | Switchgear, buildings, trenching | 5–10 million | Ground conditions, space constraints |
Economics: CAPEX, Tariffs, and Payback
From an economic standpoint, the port-side business case compares annualized CAPEX plus OPEX against shore power revenues and any external funding (grants, green bonds) while accounting for the cost of carbon and local pollutants. From the shipowner perspective, the comparison is between auxiliary fuel cost at berth and electricity tariffs, adjusted for any differentiated port dues or regulatory compliance costs.
Illustrative Annual Economics for a Container Terminal Shore Power Project
| Parameter | Value | Notes |
|---|---|---|
| Total port-side CAPEX | EUR 30–45 million | Two high-capacity berths, partial redundancy |
| Annual energy delivered | 90–140 GWh/year | Assumes 50–70% of eligible calls connect |
| Average electricity sales price | EUR 110–150/MWh | Cost-reflective plus margin vs grid wholesale |
| Gross revenue from energy | EUR 10–18 million/year | Excludes connection fees, capacity charges |
| OPEX (incl. maintenance, losses) | EUR 2–4 million/year | 2–4% of CAPEX + variable costs |
| Indicative simple payback | 6–11 years | Before grants; sensitive to utilization and spreads |
Example Value Stack: Shore Power Project NPV Components
Ten-Year Cashflow: Business-as-Usual vs Port Electrification
Practical Tools for Port Electrification Business Cases
To convert this benchmarking into port-specific numbers, you can use:
- LCOE Calculator – to compare the levelized cost of electricity from different grid and onsite supply options feeding shore power systems.
- Global Energy Price & Carbon Index – to benchmark local grid prices and emission factors when evaluating shore power vs auxiliary fuel.
Case Studies: Northern Europe, US West Coast, and Asia
Case Study: Northern European Container Terminal
Context
- Location: Major North Sea hub
- Traffic: ~2.5 million TEU/year; ~1,200 shore-power-capable calls
System
- Two berths equipped, each up to 12 MVA shore connection
- Connection to 110 kV grid via new 40 MVA substation
Results
- Electricity Delivered: ~95 GWh/year (2024)
- CO₂ Reduction: ~55–65 ktCO₂/year vs MGO at berth
- Simple Payback: ~8 years after EU and national grants
Case Study: US West Coast Cruise Terminal
Context
- Location: Pacific cruise hub
- Traffic: ~250 cruise calls/year; stringent local air-quality rules
System
- One 16 MVA cruise berth with 50/60 Hz shore power
- Tariff structure with fixed connection fee + energy charge
Results
- Grid Mix: Low-carbon (hydro and renewables >70%)
- Emission Reduction: >80% CO₂e at berth; >95% NOₓ and PM
- Economic Outcome: Payback ~10–12 years; strong social license benefits
Case Study: Asian Mixed-Use Terminal
Context
- Location: High-growth Asian port city
- Traffic: Mix of container, Ro-Ro, and cruise
System
- Modular shore power units shared across two berths
- Connection to 22 kV urban grid with limited spare capacity
Results
- Utilization: ~30% of eligible calls equipped to connect by 2025
- Challenge: Higher grid emission factor narrows net climate benefit vs LNG auxiliaries
- Response: Port exploring PPA-backed green electricity contracts
Global Perspective and Regulatory Drivers
Regulators increasingly treat shore power as a key lever for decarbonizing port emissions. The EU's FuelEU Maritime and AFIR frameworks, California's At-Berth Regulation, and initiatives in China and other Asian countries are converging on requirements for shore-power-ready newbuilds and mandatory connection for certain ship types and frequencies of call.
Devil's Advocate: Utilization, Grid Impacts, and Fair Cost Sharing
Utilization Risk
- Ship readiness: Many existing vessels are not yet equipped for shore power, limiting near-term utilization.
- Operational practices: Short calls or tight schedules can reduce willingness to connect if procedures are slow.
Grid and Infrastructure Constraints
- Local grid capacity: Some ports lack sufficient headroom without major reinforcement.
- Emissions relocation: In carbon-intensive grids, shore power reduces local air pollution but may deliver modest net GHG gains unless paired with renewables.
Cost Allocation Challenges
Questions remain on how to share CAPEX and OPEX between port authority, terminal operator, and shipowners. Models range from port-led investments recovered via port dues, to PPPs or user-pay connection charges. Poorly designed schemes risk deterring use.
Outlook to 2030/2035: Integrated Port Electrification Roadmaps
By 2035, leading ports are likely to operate integrated electrification plans that combine shore power, crane and yard equipment electrification, and onsite renewables or storage. Ports will become active energy nodes, coordinating with grid operators to manage high, coincident shore loads and support flexibility markets.
Step-by-Step Guide for Port Authorities and Terminals
1. Map Current and Future Call Profiles
- Compile data on ship types, sizes, call durations, and berth occupancy over multiple years.
- Forecast future traffic and the share of shore-power-ready vessels by segment.
2. Establish a Baseline Emissions and Cost Model
- Quantify auxiliary fuel use at berth by ship type and estimate current CO₂, NOₓ, SOₓ, and PM emissions.
- Model avoided fuel consumption and emissions under different shore power uptake scenarios.
3. Screen Infrastructure Options and Phasing
- Prioritize berths with the highest emission density and share of future-ready vessels.
- Evaluate central vs distributed converter stations, cable management options, and integration with existing substations.
4. Design Tariffs and Incentives
- Develop transparent electricity tariffs that cover costs while incentivizing connection.
- Consider differentiated port dues or rebates for shore-power-using vessels.
5. Implement, Monitor, and Iterate
- Deploy metering and digital systems to track utilization, emissions, and financial performance.
- Continuously refine procedures to minimize connection time and operational friction.
FAQ: Shore Power and Cold Ironing
Frequently Asked Questions
1. Does shore power always reduce greenhouse gas emissions?
Not always. Emission reductions depend on the carbon intensity of grid electricity relative to auxiliary fuels. In low-carbon grids dominated by renewables or nuclear, CO₂ reductions can exceed 70–80%. In coal-heavy systems, net CO₂ gains may be modest unless shore power is paired with green PPAs or onsite renewables.
2. What payback period do ports typically target for shore power investments?
Many port authorities and terminals target simple paybacks of roughly 8–12 years, often supported by grants or concessional finance. Projects driven mainly by regulatory compliance or air quality objectives may accept longer paybacks, especially where social and health benefits are material.
3. How quickly can a ship connect to shore power?
With well-designed systems and trained crews, connection times of 30–60 minutes are common, including safety checks. Initial operations may take longer, but process optimization and standardized procedures can reduce time and minimize schedule impacts.