Building out the power grid can be prohibitively expensive, which is why in many countries, like Haiti, less than three quarters of the population have grid access. Pike Research’s Clint Wheelock says just for the transmission portion alone it can cost at least $500,000 per mile. And that’s without the distribution portion and any kind of the grid intelligence (smart grid) that is getting all of the investment this year.
The cost of building such a system is compelling, as is the cost of maintenance, including the very real problem of preventing people from tearing down the wires or ripping up other installations to steal and sell the copper or whatever else of value that can be stripped. There's a compelling parallel:
While developed nations slowly replaced landline telephones with cell phones, developing countries completely skipped traditional telephone infrastructure and got their first communications via cellular. The reason is pretty simple — the cost of connecting every home with a landline is a lot higher than dropping a cellular base station every couple of miles.The appropriate technology is distributed generation.
Solar is already a commercially proven technology well-suited to distributed generation in remote or off-grid areas. However, it doesn't work at night and is still relatively expensive compared to other sources (although the cost is coming down.) Small wind also is good for distributed generation, although it too is limited by intermittency and variability. Of course, the scope of the need is broad, and available renewable resources vary widely. The full range of available technologies will be needed to fully address energy demand in the developing world.
Where flowing water is available, e.g. from streams and rivers, hydrokinetic power has promise, especially since it can run at night and when there is no wind. It can run continuously as long as the water flows. It also costs less than either small solar or small wind. We expect Hydrovolts turbines will play a significant and valuable role in providing electricity in many parts of the world. A 5kW turbine can provide the electricity to keep a refrigerator of vaccines cold, to power a communications base station, and to light a school. These things will have a powerfully positive impact on the lives of billions of people.