“Also, these areas are essentially brownfield sites, so sticking a turbine up in terms of consent and environmental issues, etc, shouldn’t be as difficult as in some other locations. Ports have to be at the coast by definition, and it is probably fairly windy there because it will generally be flat.”

And ports can benefit from the “green”drive in more ways than through wind and solar power projects; with the huge increase in interest in biofuels, they can also gain revenue from imports such as woodchips, palm kernels and grain.

North East Lincolnshire economic development officer Kate Walker says the council is handling enquiries from nine different companies looking to set up bioethanol or biodiesel plants near the port of Immingham – grain will be sourced from the farms in the port’s hinterland but more will be needed and these extra supplies will come in through the port. There are also more unusual projects, such as that at Portland on the UK’s south coast, where plans are progressing to store natural gas in salt caverns below the port estate.

The Port of Bristol has started ground preparation work for the construction of three 3MW turbines at Avonmouth Docks. Due to arrive in July, the turbines will provide about three-quarters of the port’s electricity needs, including tenants. More are likely to follow and possible locations are being considered for these, says Bristol Port Company chief executive Simon Bird.

The project will be Ecotricity’s largest Merchant Wind Power (MWP) development to date. “By choosing renewable energy over conventional, the Bristol Port Company will save over 15,000 tonnes of carbon emissions a year,” says the company. “The project highlights Ecotricity’s commitment to developing highly efficient land-based wind turbines on brownfield and industrial sites, rather than within areas of outstanding natural beauty.”

However, working on a brownfield site can make foundation work complicated. At Bristol, the ground is full of large chunks of concrete – these have to be removed and the holes filled with a granular material before piling and foundation work can begin.

Through its MWP system, Ecotricity builds and operates wind turbines on partner sites, taking on all the capital costs of the project and the feasibility, planning, installation, operation and management of the wind turbines.The MWP partner agrees to purchase the electricity from the turbine, receiving a dedicated supply of green energy at reduced rates.

According to Ecotricity, wind power now costs the same as conventional electricity – the manufacture of wind turbines is becoming cheaper and more efficient, and unit prices of electricity from wind power have come down from 11p in 1992 to around 2p today, making it the cheapest form of renewable energy. One port ahead of the crowd is Liverpool, which installed six turbines on the river wall at Seaforth in 1999. These generate 600kW each – but what comes next will be a lot larger.

“We have planning permission for a further five turbines which will produce 3MW each,” says Mersey Ports chief engineer Tim Bownes.“They will go further towards Liverpool but will still be on the river wall.”

The original six are quite distant and were easy to position because they were in an area where nothing else was going to be done in terms of port operations, he says – but the second batch will be more of a challenge. “Because they are bigger they have to be spaced further apart because of turbulence issues, and also they will be in an area where there is quite a lot of operational activity,” he says.“The existing turbines are 50 metres high to the rotor and the diameter of the blades is 44 metres. The new ones will be 90 metres high, with blade diameter of 90 metres – a dramatic increase.”

According to Mr Bownes, local people “have really come to terms with the present turbines. “We were completely open and frank about the difference in size of the new turbines but both residents and the local council were positively behind the project.The only issues we had to deal with in any real sense were comments related to mobile phone transmissions and aircraft radar – and that is common to turbines all over the place.”