Low-cost technology is already improving the quality of life in rural, off-grid communities.

Elon Musk said he had the developing world in mind when he initiated the Powerwall project. On a planet where 1.3 billion people are not connected to the electric grid, a technology that can take advantage of locally produced power will be instrumental in expanding energy access to areas where the grid has not yet reached.

If you have no or limited access to electricity, you're faced with a stark choice: burn expensive kerosene at night, or sit in the dark.

Could solar-plus-storage be an economic option?

At $3,000 for a Tesla Powerwall storage unit alone, the technology is well beyond the reach of the world's poor. However, one U.K. company is offering combined solar and storage to 11 African nations on a "rent-to-own" basis that takes 18 months or less for most customers to pay off.

Azuri Technologies has a variety of pilot schemes across sub-Saharan Africa and is about to provide 100,000 homes and businesses in Ghana with two different packs that include PV, lithium-ion energy storage, LED lighting and phone recharging. After paying a small one-time installation fee, customers pay in regular weekly installments -- often via their cell phones.

For the basic system, this payment unlocks the unit, allowing it to harvest the sun's energy and store enough electricity for six hours of phone recharging and light from two of Philips' specially designed LED lamps. Without phone recharging, the period of light goes up to nine hours for two lamps, and up to 18 if you restrict yourself to one. A larger, slightly more costly unit offers up to four lamps to illuminate a dwelling, plus additional recharging facilities.

"Although the price varies from country to country," explains marketing director Emily Ord, "we ensure that the weekly payment will be less than our customers would otherwise have to spend on kerosene and mobile call recharging. To give a guideline price, in Kenya, for example, the total cost paid by households ranges from $130 to $180 (according to distributor and region), paid over 12 months. This equates to $2.50 to $3.50 per week."

Once the total cost has been paid in installments, the unit is permanently unlocked, available to be used by the owner whenever they want. Azuri keeps its prices affordable by using appropriate technology to meet the very specific needs of the market. 

Although energy consumers in developed countries may opt for more flashy systems from Tesla, consumers in the developing world will be better served by lower-cost alternatives.

"Having high energy density and expensive storage in attractive boxes is not the priority. Other more conventional (and cheaper) battery technologies could do the job," said Dr. Jonathan Radcliffe, a senior research fellow in energy storage at the University of Birmingham in the U.K.

Existing, cost-effective storage solutions are available today. What we need is an understanding of market conditions and appropriate business models to exploit them.

(This news story is from Green Tech Media)