Rocky Mountain Institute

New rungs for the unelectrified to climb the solar energy ladder

d.light S300 charger
d.light
Solar product manufacturer d.light calls itself a "global social enterprise," with products such as this solar charger and lantern in 62 countries.

Access to electricity is crucial for sustainable economic development. Yet 1.3 billion people around the world live without basic access to electricity.

Many of these people rely on unhealthy, polluting kerosene lamps for nighttime lighting. Those with access to electricity in the developing world often rely on coal- or diesel-based grid power. Thus electrification is both a humanitarian issue and a climate issue. Access to electricity improves health, education, economic development and overall quality of life. But electrifying populations by expanding an already dirty and unreliable grid greatly would increase carbon emissions — by an estimated 141 percent in Sub-Saharan Africa and India by 2040 under business as usual.

That’s the current energy ladder. It’s not only far too great a leap for the unelectrified to reach the other end, but the world can’t afford for them to reach the other end by burning more fossil fuels. And although many people are forecast to gain electricity access in the next 20 years in the developing world, population growth in those regions will offset almost all of it.

“The system today to provide power to the rural poor across the developing world isn’t working,” said RMI manager Roy Torbert. “We are on track to have as many people in 2030 without access to power as we do today. A new approach is needed.”

Thus the crucial need for solar energy. Decentralized solar energy provides clean, reliable, low-carbon electricity, and can power communities both large and small. A new solar-based energy ladder, with each rung in reach of the next, can enable families and communities to climb out of energy poverty to energy access, thereby supporting economic development and eventually halting coal’s expansion.

It would start with solar lanterns, move to solar home systems, then to mini-grids and eventually community-scale microgrids. With community-scale microgrids, you enable real commerce — with sewing machines, wood lathes and other productive uses beyond the capacity of solar lanterns and solar home systems.

The bottom rungs

Over 250 million households (PDF) use kerosene for lighting. This has devastating consequences for the women and children who breathe kerosene fumes daily — equivalent to smoking two packs of cigarettes a day (PDF). Fortunately, many entrepreneurs around the world have achieved impressive success with solar lanterns, which provide better-quality light than kerosene lanterns without any harmful fumes. D.light, a company that manufactures affordable and rugged solar lanterns, has sold over 9 million solar lights in 62 countries since its founding in 2006.

Fifty Lanterns International is a nonprofit organization providing solar lanterns to people in communities torn by poverty, war or disaster. Its current program is working with a group of 7,000 Ugandan grandmothers who lost their children to AIDS and are now caring for their orphaned grandchildren. “For only $50 we can provide a grandmother with life-changing solar light that will help prevent open flame burns and toxic fumes,” said Fifty Lanterns executive director Linda Cullen.

Other organizations focus on small solar home systems. These systems, anywhere from 10 to 100 watts, allow people to light their homes, recharge cell phones and run a small appliance or two. These systems have proven affordable with financing, even to people earning under $2 per day. Yet this is where the current solar ladder breaks down.

While it is important to start small for affordability, there needs to be a way to grow. Being able to add solar panels modularly and having standardized solutions to create interoperability between systems will create the ability to transition from solar home systems to solar mini-grids or microgrids.

The top rungs

Modular solar mini-grids are exactly what Devergy, a Dutch company working in Africa, has deployed in several villages in Tanzania. These mini-grids power households and small businesses in six villages, connecting 800 customers to clean, reliable solar power.

“After seeing many unmaintained solar home systems traveling through South America, we realized we needed to create a system that is interactive,” said Gianluca Cescon, cofounder of Devergy. “Through smart meters we can monitor what’s going on.” Devergy decided it could have a greater impact by linking many solar home systems together, and after many prototypes came out with the mini-grid it uses in Tanzania today.

“Using a modular system, designed to be interoperable and durable, communities can tailor their power supply to their individual needs, and grow their solar and battery systems according to the most relevant demands,” said RMI’s Torbert.

Bridging into even larger, community-scale microgrids will enable development that supports quality of life and countries’ economic aspirations, and halt coal's expansion into these to-be-electrified parts of the world. “We need to bridge the gap between household or small business use and more energy-intensive productive uses such as rice milling and corn milling,” said Devergy’s Cescon.

The Solar Electric Light Fund (SELF) also has moved towards community-scale microgrids. “SELF spent years installing solar home systems in countries around the world. And it really helped change the lives of thousands,” said Bob Freling, executive director of the Solar Electric Light Fund. “But if we want to get to the next level of increased economic opportunity, we need to look beyond solar home systems to larger community scale microgrids.”

SELF’s first two solar microgrids will power a microenterprise center in Haiti and a school, health clinic and micro-enterprise facilities in Colombia. By powering larger facilities and more energy-intensive businesses, solar microgrids allow individuals, businesses and entire communities to develop and thrive.

This article first appeared at RMI Outlet.