Urban and green

As the world population grows, cities are expanding and energy consumption rising. According to a study commissioned by the German Ministry of Education and Research called "Megacities – Shaping of a Sustainable Future World," cities today are responsible for 80 percent of global energy consumption and 85 percent of greenhouse gas emissions.

Meanwhile, Germany's KfW Bank has calculated that by 2015, approximately two thirds of cities with a population of over five million will be in developing nations.

The poorer parts of the world are seeing especially rapid population growth and more people leaving rural areas for cities, creating housing shortages and pushing up rents.

Inadequate infrastructure

As a result, shanty towns often mushroom on city outskirts, with impoverished residents living in illegal, makeshift housing and paying no taxes. The infrastructure is often chaotic and inadequate.

"The city limits of major cities in countries such as India as well as in Sub-Saharan Africa, for example, lack proper infrastructure for water, electricity and waste disposal," Eberhard Rothfuss, urban geographer at the University of Bonn, says.

Residents often take matters into their own hands, laying pipes and relying on polluting diesel generators for electricity, with dire consequences for the environment.

But slums tend to vary greatly, depending on their location. "Inner-city slums tend to be better organized than those on the outskirts," says Rothfuss.

India's shanty towns, for instance, often have no infrastructure whatsoever. According to the US development aid organization USAID, only 15 percent of slum dwellings have drinking water, electricity and sanitary facilities.

For years, non-governmental organizations have worked on improving residents' lives by developing electricity grids, for example.

In 2005 the Indian government introduced the "National Urban Renewal Mission" aimed at establishing basic infrastructure in the shanty towns, including proper housing, clean water and waste water systems.

Improving life in the favelas

Access to water and electricity is more common in the shanty towns in Brazil. But many residents tap these resources illegally. They often use pipes and cables that are so dilapidated and inefficient that approximately 20 to 30 percent of energy is lost on the way.

On the other hand, many residents have also long been paying for their electricity. These days, roughly 80 percent of the Brazilian population lives in cities.

"Urbanization began fairly early in Brazil,” says Rothfuß. "The country's oldest slum is in Rio de Janeiro and emerged in the 19th century."

These long-standing favelas are better-equipped than the newer ones on the city outskirts. But residents tend to have old electrical appliances such as TVs and fridges that guzzle energy.

"The poorest households are the ones paying most for energy," Bernhard Boesl, an energy expert at the German Agency for International Cooperation, says.

But efforts are on to change the situation. A project, begun in 2008, allows the residents of Brazil's favelas to dispose of their old fridges at clean recycling centers and exchange them for new, more efficient ones.

Solar thermal energy catches on

Another scheme focuses on the installation of solar thermal energy systems to heat water. A high proportion of Brazilian households still uses electric shower heads.

Susanne Bodach, an expert on renewable energies, has calculated that using an electric shower head costs a family of four approximately 53 reais (23 euros) per month, while solar collectors cost just 15 reais (6 euros).

The initial investment costs for a solar thermal energy system might be high but it pays off within five years – and is moreover the more environmentally-friendly option.

These days, solar thermal energy systems are often integrated into social housing projects in Brazil and Mexico, although Eberhard Rothfuss is skeptical whether this boosts social and economic development.

"Governments might support certain developments projects but they don't tend to be sustainable and they don't reduce social inequality," he says.

He also points out that the residents of the slums are responsible for only a fraction of the country's total energy consumption.

"The rich blame energy waste on the poor, but in fact an affluent family uses much more electricity than a poor one," he points out.

Michaela Führer (jp)
Editor: Sonia Phalnikar