A giant network of solar panels in the Sahara desert could transform Europe’s energy supply within a decade, according to Dr Anthony Patt of the International Institute for Applied Systems Analysis in Africa, if investment could be generated and transmission challenges overcome. His findings were first proposed in 2007 at the Copenhagen Climate Conference.

Experts say only a fraction of the Sahara desert, probably the size of a small country, would need to be covered to produce enough clean electricity to supply the whole of Europe.

Speaking at the Euroscience Open Forum in Barcelona, Arnulf Jaeger-Waldau of the European commission’s Institute for Energy said it would require the capture of just 0.3% of the light falling on the Sahara and Middle East deserts to meet all of Europe’s energy needs.

The scientists are calling for the creation of a series of huge solar farms – producing electricity either through photovoltaic cells, or by concentrating the sun’s heat to boil water and drive turbines – as part of a plan to share Europe’s renewable energy resources across the continent.

The arguments against renewable sources of energy such as wind and solar center on what critics cite as the inconsistency of these sources. Since wind and sun energy vary with the weather, they cannot be considered as reliable sources for large scale energy needs. Supporters counter that renewable energy supplies would be reliable with sufficient infrastructure in place, allowing solar energy to be collected wherever the sun shines or the wind blows within an energy-sharing region. The consistent supply of sunlight in the Sahara, however, addresses the both these arguments.

In fact, harnessing the Saharan sun would be particularly effective because the sunlight in this area is more intense: solar photovoltaic panels in northern Africa could generate up to three times the electricity compared with similar panels in northern Europe. Sunshine in the Sahara is a constant resource that is rarely blocked by clouds even in the winter.

While the technology for generating electricity under this plan is already within reach, delivering the power presents the greater challenge. A network of high voltage DC transmission lines would be needed to connect countries along the route between northern Africa and northern Europe. Existing infrastructure would need major re-structuring.

Competing interests also pose a challenge to establishing a transmission network through southern Europe. Southern Mediterranean countries including Portugal and Spain have already invested heavily in solar energy, and Algeria aims to export 6,000 megawatts of solar-generated power to Europe by 2020.

There would also likely be opposition from local communities across Europe unhappy about transmission cables installed near their homes. And security and governance challenges persist, especially in countries where the rule of law is weak.

Despite these challenges, Dr Anthony Patt believes harvesting the power of the Sahara is feasible, with £50bn of government investment needed over the next decade to make the scheme a reality. The cost of moving electricity over long distance has come down and private companies, he projects, may be convinced the project is an attractive investment.

Scientists working on the project admit that it would take many years and huge investment to generate enough solar energy from North Africa to power Europe but envisage that by 2050 it could produce 100 GW, more than the combined electricity output from all sources in the UK, with an investment of around €450bn.

Doug Parr, Greenpeace UK’s chief scientist, welcomed the proposals: “Assuming it’s cost-effective, a large scale renewable energy grid is just the kind of innovation we need if we’re going to beat climate change.”