Why Renewables?

Renewable Energy sources Rio de Janeiro

Electricity in Brazil is generated largely from renewable sources, with the bulk of supply generated by large hydro-electric schemes, and significant investment in large-scale wind generation projects.

In 2011, almost 90% of Brazilian electricity was generated from renewable sources [1]. Brazil is a leading nation in terms of centralized generation of electrical power by means of renewable energy sources, and has a clear national strategy that involves increasing renewable energy capacity [2].

Brazil has one of the largest river systems in the world, and the vast majority of electric power in the country is produced from hydroelectric power stations. In addition, large scale wind, solar and biomass projects are being rapidly developed. Development of this additional renewable power will give more diversity to Brazil’s energy matrix and help secure Brazil’s energy supply. In this context, simply plugging in and using electricity from the grid would appear to be an environmentally-friendly approach.

However, there are a range of economic, strategic, environmental and social arguments that support the use of local renewable energy technology in Rio de Janeiro. Even though the electricity grid in Brazil has a renewable base, there are inherent advantages associated with micro-generation projects.

Generating electricity near the place of consumption helps improve the quality of service and reduces transmission losses. Problems associated with peak demand can be “ironed out”, and reducing reliance on centrally generated power has a number of strategic benefits.

Most of the electricity in Brazil is generated by large hydroelectric power plants. Although hydroelectricity is an extremely efficient way of generating energy, delivering this energy to Rio de Janeiro involves transmission lines that are hundreds of kilometres in length [3]. Transmission of electricity is an inherently inefficient process and grid losses in Brazil amount to 17% [4].

Brazil is heavily dependent on hydroelectricity, being dependent on one single dam (Itaipu) for more than 25% of electrical power generation. In the past, this reliance on a single energy source has been problematic. Brazil was faced with one of the most serious energy crises in its history in 2001-2002.

The crisis resulted from several years of below-average rainfall, which reduced hydroelectric generating capacity. Reservoir levels reached such low levels that supply could not be ensured for more than four months. Since then, the Brazilian government has made a significant commitment to large-scale alternative forms of energy including wind, solar and biofuels generation [2]. However, hydropower still forms the cornerstone of the electrical energy supply for Rio, and this has not been without its problems. Rio suffered a major power outage in November 2009 [5], which was primarily due to adverse weather conditions affecting transmission lines.

Micro-generation of renewable electrical energy at the building-scale (by means of solar PV or biomass/biofuel powered CCHP) can help to even out peak demand, thereby reducing reliance on central electricity generation. In addition, renewable technologies such as solar-thermal systems serve to reduce the demand for electricity, which helps reduce reliance on a single energy source. Local micro-generation of electricity can help to increase the security of supply by reducing reliance on long transmission lines.

Improve Stakeholder Control

Renewable energy projects can give building residents, local communities and other stakeholders improved control over their own energy security. Many renewable energy technologies are relatively simple (e.g. solar thermal), and residents can be trained to monitor and maintain the systems.

All stakeholders, from design professionals to the building occupants, can be included in the design process. Helping stakeholders to “own” renewable technology projects can serve to empower local communities and can even provide educational training opportunities. An example of this can be seen in the Rio Municipality solar thermal initiative for social housing [6].

Comply with the Strategic Energy Objectives of Rio de Janeiro & Brazil

Distributed generation is an excellent way to diversify energy sources, especially in the context of an over-reliance on hydroelectricity. The Brazilian government has recognised this and has made it easier for small-scale renewable energy generators to connect to the grid.

The Brazilian Electrical Regulatory Agency (ANEEL) announced last April that electricity generated by small/medium scale renewable technologies could be connected to the main electricity supply by means of smart meters. Inter-connection involves a credit-based system – when the local generator is producing excess energy, this will feed into the grid and the generator will accumulate credit [7].

The state government of Rio de Janeiro has recognised that solar thermal heating of water is an excellent way to reduce the energy demand of the city, helping to reduce GHG emissions and contribute to security of electricity supply. In order to promote the use of solar thermal energy in water-heating applications, State law makes the inclusion of solar thermal systems mandatory for new and refurbished public buildings in Rio de Janeiro, where solar energy must cover 40% of the annual hot water demand.

It has been proposed that this law will be extended to include all buildings and it is likely that this law will take effect in the near future. The city of Rio de Janeiro has plans to install solar thermal systems in 400,000 social housing apartments, including developments that are being built to re-house Favela residents [6].

Diversification of power resources is an important strategic objective for both Brazil and Rio de Janeiro. Distributed micro-generation by means of renewable technology would contribute significantly to achieving this strategic objective.

Contribute to the Rio Low Carbon City Development Program

The Rio Low Carbon City Development Program was jointly developed by the City Government of Rio de Janeiro and the World Bank. Launched in June 2012, the program aims to reduce the City’s carbon emissions by 2.3 million metric tons by 2020. This reduction is equivalent to 20% of the city’s 2005 emissions. The program will include:

  • An urban reforestation and maintenance programme
  • Bus rapid transit systems
  • An integrated solid waste management system
  • Recycling policies
  • Improved energy efficiency in buildings
  • “Bike Rio” – a bicycle rental project and bicycle pathway expansion scheme

Some of these are already underway, such as doubling the city’s network of bike paths, the opening of the first of four exclusive Bus Rapid Transit (BRT) lanes, and the universalization of basic sanitation in Zona Oeste, the city’s most populous area. The programme is certified to ISO standards and will monitor and account for climate change mitigation actions across the city, using the greenhouse gas (GHG) inventory, a measurement of the city’s total GHG emissions [8].

By law, the GHG Inventory will be updated every four years (beginning 2012), using the GHG protocol tool [9]. This will enable the city to better understand, quantify and manage GHG emissions.

Comply with Rio de Janeiro Carbon Reduction Targets

The City of Rio de Janeiro has set targets for reducing greenhouse gas emissions. These targets have been set into law. Targets include:

  • 2012: Reduce GHG emissions by 8%
  • 2016: Reduce GHG emissions by 16%
  • 2020: Reduce GHG emissions by 20%

All targets refer to a reduction in emissions compared with 2005 levels.

The city of Rio de Janeiro has committed that all works, programs, activities and projects should consider the objectives of reducing GHG emissions. This principle will also inform planning policies [10]. Implementing renewable technology and energy efficient design will help building projects to comply with the legislation.

Provide Social & Environmental Benefits

In the face of rapidly increasing demand for electricity, Brazil aims to expand generation capacity by means of sustainable technologies. This, however, is not without it’s problems. The new dam planned for Belo Monte is currently caught up in litigation, with the Federal court having ordered a suspension of construction work in August 2012. The project faces fierce opposition from the Brazilian green movement, who estimate that between 20,000 and 40,000 people will be displaced by the project [11].

Locally-based renewable energy projects would reduce the demand for large centralised projects, ensuring security of energy supply without adversely affecting communities and ecosystems.

Achieving Credits under Environmental Certification Schemes

With an increasing focus on sustainable development, public and private clients in Rio are starting to require that their buildings achieve LEED, BREEAM, or AQUA certification.  These are third party environmental certification schemes that provide recognised benchmarks for the design, construction and operation of sustainable buildings.

A high proportion of credits in each of the schemes mentioned are determined by energy use. Energy efficient design and the use of renewable or low carbon technologies are essential for projects that are aiming to achieve high ratings.


  1. “BALANÇO ENERGÉTICO NACIONAL,” 2012. Available: https://ben.epe.gov.br/downloads/Resultados_Pre_BEN_2012.pdf [Accessed: 20-Sep-2012]
  2. “Ten Year Plan for Energy Expansion Brazil,” Brasilia, 2010. Available: http://www.epe.gov.br/PDEE/20120302_1.pdf [Accessed: 20-Sep-2012]
  3. “Transmission Expansion in Brazil for Renewables.” [Online]. Available: http://www.ieee.org/organizations/pes/meetings/gm2012/slides/pesgm2012p-001808.pdf [Accessed: 17-Sep-2012].
  4. “Electric power transmission and distribution losses,” World Bank, 2012. [Online]. Available: http://data.worldbank.org/indicator/EG.ELC.LOSS.ZS [Accessed: 25-Sep-2012].
  5. “Brazilian power cut leaves 60 million in the dark,” The Guardian. [Online]. Available: http://www.guardian.co.uk/world/2009/nov/11/brazil-power-cut-rio-madonna [Accessed: 18-Sep-2012].
  6. “A thousand solar roofs for Brazil | Global Ideas.” [Online]. Available: http://www.youtube.com/watch?v=U9q7x_CxN1c&feature=BFa&list=FLFXQKmejUaemgXA4DFDkt9A [Accessed: 18-Sep-2012].
  7. “ANEEL approves rules to facilitate the generation of energy in consumer units.” [Online]. Available: http://www.aneel.gov.br/aplicacoes/noticias/Output_Noticias.cfm?Identidade=5457&id_area=90 [Accessed: 17-Sep-2012].
  8. “City of Rio and World Bank Launch Ground-Breaking Program for Low Carbon City Development,” Rio Prefeitura, World Bank, 2012. [Online]. Available: http://www.dnv.com/binaries/Press_Release_Low_Carbon_Event_June_18_2012_Eng_FINAL_tcm4-520458.pdf [Accessed: 11-Sep-2012].
  9. “City GHG Accounting,” Greenhouse Gas Protocol, 2012. [Online]. Available: http://www.ghgprotocol.org/city-accounting [Accessed: 11-Sep-2012].
  10. Decree n. ° 31414 [Online]. Available: http://www.resol.com.br/textos/decreto_no_31414_de_30_de_novembro_de_2009_-_metas_de_reducao_de_gee_no_mrj.pdf
  11. “Belo Monte dam caught up in litigation – UPI.com.” [Online]. Available: http://www.upi.com/Business_News/Energy-Resources/2012/08/17/Belo-Monte-dam-caught-up-in-litigation/UPI-90571345207149/?rel=86031345821304 [Accessed: 17-Sep-2012].