What’s the best way to bring electricity to everyone?

When it comes to bringing affordable, reliable electricity to all people, opinions differ on the ideal problem solving approach. Energy specialists think a lot about energy density and quality/intermittency. Economists think about cost. Planners think about space. Each of these caricatures highlights an important consideration, but apparently the energy world needs more planners because space seems to have been somehow lost in the electricity access conversation.

By space, I mean where the people who lack electricity live and work. And by conversation, I mean the dialog between two schools of thought (summarized thoughtfully here, though with an emphasis on climate change): the first believing that anything less than a full connection to the centralized electric grid is insufficient, and the second espousing distributed solar power as the way of the future. Once you begin to actively consider space, however, this debate seems unnecessary –  each solution has its place, in the right context.

Meeting energy needs in urban areas

Experts have focused increasing attention on the concentration of energy use in urban areas, which account for about 70% of global energy consumption. This share is only going to grow, since the global ‘urban’ population is projected to significantly outpace total population, with nearly 3 billion new people in cities by 2050.

Bill Gates’ blog post on energy access caused a stir late last June, and his argument for centralized power is reasonable in many urban areas. As data from The World Bank shows below, every country [in the dataset] with an urbanization rate of at least 86% also has an electrification rate of at least 95%; with at least 60% urbanization, none have less than 80% electrification. It is both cheaper and logistically easier (not ‘easy’ though, per se) to bring electricity to urban residents.

Source: data from The World Bank

Proponents of both centralized and distributed generation argue that their preferred technology is cheaper and provides improved quality of service, and both are right – sometimes. Transmission infrastructure to supply power from remote generation sources to central cities is more cost-effective simply due to the sheer number of sufficiently high-income customers that utilities can count on to purchase electricity. Distribution costs also come down with increased population density. When fuel costs are low these factors typically make centralized power generation cheaper, at least in cities.

This might be especially important to would-be fossil fuel generators, as with increasingly stringent pollution controls and public health awareness, coal- or oil-fueled power plants are unlikely to survive in densely populated urban areas. Most countries do not have policies in place to discourage power plant development in highly urbanized regions, though evidence of such plants’ adverse consequencescontinues to mount, with China (who, perhaps not coincidentally, just announced a planned national emissions trading system) providing the clearest example.

Meeting energy needs in rural areas

While more and more people are moving to cities, five out of every six people without electricity still live in rural areas. Getting electricity to these people requires bringing power to them by extending existing grid access and building new distributed generation, or (arguably) waiting for them to move to cities.

The latter does not make sense, because (1) we only believe that many of them will move to cities, and (2) we have no idea which ones will move to cities, from where, how quickly. The extension of a national electric grid can take several decades (see graph from the Global Energy Assessment, below) and requires large infrastructure investments. This does not justify delay but rather serves as a call to action: we need to find alternative means of meeting electricity needs on an accelerated time scale.