The African Rift Geothermal facility project aims to tap the heat trapped in rocks deep beneath the floor of the geological feature that runs from the Red Sea to Mozambique.
"Oil today is $57 a barrel. That is sucking up every cent of development aid to Africa," a spokesman for the UN Environment Programme said on the margins of a meeting of environment and development ministers from the Group of Eight rich nations.
"It is a huge problem for Africa. This really is a matter of life and death. This could be the answer to their prayers," he said.
A recent report by the US Geothermal Energy Association calculated that the hot rocks beneath the rift valley could produce up to 6.5 gigawatts of energy.
But to date only Kenya is making any effort to exploit the resources that literally lie under their feet - and even then there are only 121 megawatts of geothermal electric power installed.
"Oil today is $57 a barrel. That is sucking up every cent of development aid to Africa"
UN Environment Programme spokesman
The Rift Valley runs through Sudan, Ethiopia, Eritrea, Djibouti, Somalia, Kenya, Uganda, Rwanda, Burundi, the Democratic Republic of the Congo, Tanzania and Malawi through Mozambique.
"The potential benefit for these energy-starved countries is vast," the UNEP spokesman said.
A paper prepared for the World Geothermal Congress in Turkey in April makes the point that not only is geothermal energy an environmentally clean power source, but in Ethiopia, Eritrea and Djibouti it is the only indigenous energy source.
But there are huge technical let alone financial obstacles to overcome first.
The existing drilling technology - mostly based on oil exploration - is not suited to the very high temperatures experienced when trying to tap geothermal sources, and start-up costs can be prohibitive.
The UN and its partners are busy raising the finance for the pilot project which they hope will get under way this year.