UK Ports Warn Grid Delays, Energy Costs Threaten Maritime Decarbonization

Britain’s ports will need dramatically more electricity over the coming decades to support shore power, vessel charging and alternative fuels, but long waits for grid connections and high energy costs risk slowing the maritime sector’s transition to net zero, according to a new UK government report.

The Department for Transport on Friday published its summary of responses to the “Net Zero Ports: Challenges and Opportunities” call for evidence, launched alongside the government’s Maritime Decarbonisation Strategy in March 2025.

The consultation drew 65 responses, including 17 port companies, 11 trade associations and four shipping, cruise and ferry companies. The government said the exercise was intended to better understand the infrastructure, energy and regulatory challenges facing ports as the UK seeks to eliminate domestic maritime greenhouse gas emissions by 2050. 

Electricity emerged as one of the biggest issues. Major UK ports currently operate with grid connections typically measured in megawatts, with respondents reporting a median capacity of 5.5 MW and an average of 11.73 MW. Several ports are already operating at or near their available capacity. 

Those requirements are expected to rise sharply as ports electrify cargo-handling equipment, install shore power and vessel charging systems and develop infrastructure for alternative marine fuels.

Port companies estimated that their electricity capacity requirements could grow by between two and 10 times current levels, reaching an average of around 91 MW. Most also said upgrades already being planned would not be sufficient to cover all of their expected future demand. 

Getting that additional power could take years. Several respondents reported difficulty obtaining timely and affordable grid upgrades, with connection lead times reaching as long as 15 years. In one case, a port that had initially been offered phased connections before 2030 was later told it could have to wait until 2039 because of wider transmission constraints. 

The problem is already affecting investment, according to the report. Of 26 respondents asked whether insufficient electricity supply had caused ports or their customers to lose opportunities, 69% said yes. Some warned that cruise and ferry operators were choosing European ports because of better shore power availability and lower electricity prices, while others said grid constraints were discouraging investment in electric vessels and green fuel production. 

Alternative fuel infrastructure faces many of the same problems. Ports reported plans involving methanol, hydrogen, ammonia, biofuels and electric vessel charging, but identified grid constraints, high capital costs, uncertain future fuel demand and regulatory complexity as major obstacles.

Respondents estimated that full development of alternative fuel bunkering and charging infrastructure would generally take five to 10 years, while some projects could stretch as far as 2050. Estimates for electric charging infrastructure ranged from £45,000 per berth to more than £20 million, depending largely on vessel size and electricity requirements. 

The consultation also examined a possible UK requirement to reduce emissions from ships while at berth.

Of 51 respondents, 76% agreed or strongly agreed that such a requirement could reduce greenhouse gas emissions around ports. Shore power was widely viewed as the most mature option, although respondents warned that high capital costs, grid constraints and vessel retrofit costs remain significant barriers. 

Industry also pushed for any UK rules to align with international measures, including the International Maritime Organization’s Net-Zero Framework and the European Union’s FuelEU Maritime regulations, rather than creating another standalone regulatory regime. 

The UK Chamber of Shipping said the findings reinforced the need to address infrastructure alongside regulations such as the UK Emissions Trading Scheme and forthcoming Fuel UK Maritime rules.

“We welcome the Department for Transport’s recognition that ports and shipping are central to the UK’s clean growth ambitions, and that grid capacity, energy costs and infrastructure delivery are now among the biggest barriers to maritime decarbonisation,” said Francesco Sandrelli, the Chamber’s Environment Policy Director. “The priority now must be delivery.”

Sandrelli warned that regulation by itself would not drive the transition. “Without that, there is a real risk of creating a ‘pay to pollute’ system that does little to accelerate decarbonisation,” he said.

He added that ship operators need confidence that alternative fuels, shore power and related infrastructure will be available where needed and at commercially viable prices.

The concerns extend beyond infrastructure. Among 47 respondents asked whether there was sufficient government guidance to help ports decarbonize, 68% said there was not. Respondents called for clearer long-term policy, faster grid connections, public funding, electricity cost reform and better alignment between UK and international regulations. 

The Department for Transport said the findings will inform the next stage of its maritime decarbonization program, including further work with ports, shipping companies, energy networks and fuel providers.

A stakeholder webinar is scheduled for September 24 to discuss the findings and future policy development.

Editorial Standards · Corrections · About gCaptain

Subscribe for Daily Maritime Insights

Sign up for gCaptain’s newsletter and never miss an update

— trusted by our 104,935 members