A Better Energy Grid for the Developing World

Ph.D. student Christian Casillas is helping to bring reliable electricity to rural Nicaragua. (Photo by: R. Norgaard.)

According to the UN, lack of access to electricity and fuel in rural areas contributes to 1.6 million deaths per year and perpetuates poverty. For engineers and energy suppliers working in this environment, bringing power to these populations requires a multi-pronged effort, not just to build the grids themselves, but also to plug into the human factors of operating within a particular culture and under what is usually a cash-strapped government. Christian Casillas, a Ph.D. student advised by Professor Daniel Kammen in the Energy and Resources Group, is balancing these two sides of the problem, working out the details of a roadmap to bring reliable electricity to the fishing villages along Nicaragua’s eastern coast.

Many of the challenges are more social and political than technical, and Casillas must engineer his solution to fit Nicaragua’s state-owned utility ENEL (Empresa Nicaragüense de Electricidad). This national electric company, which supplies subsidized power to rural areas, has operated at a loss ever since 1997, when Nicaragua sold off its more potentially profitable urban grids to private companies under guidance from the World Bank.

To bring power to its customers, ENEL typically ships a monthly allotment of fuel to diesel generators that run the “microgrids” in isolated areas. Diesel generators don’t produce power as cheaply or cleanly as large-scale power plants, but people in remote areas worldwide rely on them for their electricity, at least until the tank runs empty or the generator breaks.

“The U.S. model for rural electrification—which involves extending transmission and distribution lines from large centralized generation plants to rural areas—is expensive,” Casillas explains. “Today it costs 15 thousand to 20 thousand dollars to extend existing high-voltage lines just one kilometer. In many countries, this kind of capital just doesn’t exist.”

Dock in the coastal town of Orinoco, Nicaragua. (Photo by Christian Casillas.)

With approval from ENEL, Casillas has been studying how power is generated, used and managed in rural Nicaragua, focusing on the coastal town of Orinoco. Spending time there and working with the local ENEL office, he has identified several ways to improve Orinoco’s power infrastructure using methods that involve both hardware and the “software” of rate structuring and other policies.

For example, homes in Orinoco don’t have power meters; instead, a local utility representative goes door to door to see what people have plugged in, then assesses a charge based on their constant use. Consequently, people keep everything on all the time to get their money’s worth. Installing usage meters, a move that local residents support, would save them money when they power things off. Another possible improvement: more efficient lighting. If the utility bought everyone compact fluorescent light bulbs to replace their incandescent bulbs, their savings on subsidized fuel would pay back the outlay in just four months.

On the rate side, electricity customers pay a baseline of $3.60 per month for up to 15 kilowatt-hours, plus 26 cents for each additional kwh. This regressive pricing structure discourages baseline customers from conservation and charges the least demanding users, who are frequently the poorest, the highest cost per unit. Restructuring the billing to encourage conservation, along with installing meters and increasing efficiency, will make each tank of generator fuel last longer; and if there’s enough fuel to run the grid 24/7, increased efficiency will still lower everyone’s costs and pollute less.

With fuel prices high, Casillas is also working with the nonprofit blueEnergy (co-founded by Berkeley Engineering alumnus Mathias Craig) and Berkeley’s RAEL (Renewable and Appropriate Energy Laboratory) on recipes for supplementing diesel microgrids with small-scale wind and solar power, generated with simple equipment that can be assembled and repaired locally. “Ten years ago, a small diesel generator could produce power at 12 to 15 cents per kilowatt-hour. Now that fuel costs have risen, it’s 30 to 40 cents, which begins to make power from diesel generators comparable in cost to power from solar and wind generators over the lifetime of the equipment,” says Casillas.

Community members repairing a wind turbine. (Photo by Christian Casillas.)

Based on his Orinoco experiences, Casillas hopes to formulate a plan for saving money and improving services that ENEL could roll out in all 32 microgrids along Nicaragua’s eastern coast. At the same time, he wants to identify the social conditions that are most conducive to community management of microgrids. Local power co-ops operate successfully along Nicaragua’s west coast, where a linguistically and ethnically homogeneous population earns year-round income from farming. But they haven’t worked in the sparsely populated, mountainous east coast villages, where a polyglot population depends on seasonal fishing. Local utility workers there had trouble collecting payments until they became ENEL employees and printed their bills on official stationery.

“It is nice to focus on the technology itself, because there are hard boundaries with definite solutions,” Casillas explains. “But whether we’re dealing with a more efficient stove or cheaper  electric lighting, successful implementation for a rural community can be achieved only by understanding the needs and motivations of the people who may benefit from it. I love the science, but for me personally, the social considerations give it a valuable context.”

While access to electricity lowers mortality, provides opportunities and is vital to people’s health, Casillas points out that it also may have benefits that are less tangible. “Locals have told me that when the grid is up and the street lights are on, the town is more alive. People feel more secure. You see them walking along the street, talking with neighbors. It may be good for the entire community.”