The UK and US will work together to develop "floating" wind turbines to harness more offshore wind power at a potentially lower cost, the government said on Monday.

Before this week's clean-energy meeting of ministers from 23 countries in London, the government announced it will collaborate with the US in developing wind technology to generate power in deep waters that are currently off-limits to conventional turbines.

In order to exploit the UK's huge wind resource, which accounts for about one-third of Europe's offshore wind potential, new technology is needed to access waters between 60 and 100 metres deep: too deep for turbines fixed to the seabed, but where wind speeds are consistently higher.

It is hoped that developing the technology will increase the UK's potential for offshore wind power, particularly after 2020, by which time many shallower sites will have been developed.

The government believes it could also reduce the current high cost of offshore wind, cutting the expense of seabed foundations and allowing repairs on floating wind platforms to be carried out in port rather than out at sea.

The energy secretary, Ed Davey, said: "Britain has more wind turbines installed around its shores than any other country in the world, and our market is rated year after year as the most attractive market among investors. Offshore wind is critical for the UK's energy future, and there is big interest around the world in what we're doing.

"The UK and US are both making funding available for this technology, and we're determined to work together to capitalise on this shared intent."

The Energy Technologies Institute is commissioning a £25m offshore wind floating system demonstrator, which will require the chosen participants to produce an offshore wind turbine that can generate 5MW to 7MW by 2016. The project could be demonstrated off the Cornish coast at the WaveHub site.

In the US, four offshore projects are being backed by the Department of Energy, potentially including a floating wind demonstration.

Norway already has a full-scale demonstration of a floating wind turbine, while a similar project is underway off Portugal.

This week's Clean Energy Ministerial will be co-chaired by Davey and his US energy counterpart, Steven Chu. The two countries are signing a memorandum of understanding to collaborate on a series of areas including power generation, energy efficiency and transmission.