Solar Makes Sense for Rural Electrification: My Off-Grid Solar Energy System in Brazil
Off grid solar energy system in Brazil
By Alice Antunes*
*Guest Blog Post: Alice Antunes is a senior at Georgetown University and an intern this semester at SolarTown. Her family was an early adopter of solar energy in Brazil. We invited Alice to blog about her solar home and what compelled her family to become pioneers in solar energy.
My family installed a solar energy system in rural Brazil twelve years ago. A little bit of social consciousness and a lot of economic reasons persuaded us that solar energy was the way to go for our home in Minas Gerais in the interior of Brazil. This is our first-hand account of how and why we went solar.
Our decision to go solar in 1999 to replace kerosene lamps
We began renting a plot of land in rural Brazil, in the state of Minas Gerais in 1997, in which there was a little house that should really have been called a cabin. Living in São Paulo, this served as a weekend home where we could take advantage of life away from the city.
Access to the house was and still is restricted to one dirt road. At the time, there was no electricity, since power lines stopped several kilometers away from us. For the first two years, kerosene lamps lit our lives at night. The electricity grid was not and has not been extended, despite our good efforts. In 1999, my parents decided to buy the property and install home solar panels to replace the kerosene lamps, radically transforming our electricity consumption there.
A description of the fazenda
Today, the fazenda Sobradinho, as we call it, has three houses: a main house, a foreman’s house and a guesthouse. The main house and foreman’s house were already there when we started visiting the fazendain 1997. The guesthouse was built in 2006. With more structures and more guests, we have needed more electricity, and home solar panels have been the best answer for our energy needs.
We installed our first solar energy system on the rooftop of the main house in 1999. It provided energy for lamps, but was insufficient for providing energy for household appliances. This system was upgraded and transferred to the foreman’s house in 2004, and a new solar panel system was installed at the main house. In 2006, both existing installations were upgraded and the newly constructed guesthouse was fitted with its own rooftop installation.
The details of the solar energy system
Altogether our solar energy system is a 1.5 kW installation, with 600 watts at the main house, 525 watts at the foreman’s house and 100 watts at the guesthouse. All solar modules are between 50- and 75-watt polycrystalline panels, which by today’s standards are very small—but not then. Additionally, a radio tower for telephone signals is powered by one 50-watt polycrystalline module. Each module has 36 cells, was manufactured by Solaris, a Brazilian solar manufacturer, has an efficiency of about 15%.
Solar battery systems back each installation: the main house is backed by six 180-amp batteries, the foreman’s house by four 180-amp batteries, and the guesthouse and radio tower by one 180-amp battery. Each system has charge controllers specific to small and medium solar installations to keep the batteries from overcharging.
The system was installed on my family’s initiative, pushed by the lack of support for grid extension, without government support or incentives. The price per watt today is a quarter of what it was twelve years ago, when the solar energy system was installed.
Small solar energy system packs a lot of power in remote places
The system may seem small, but it is enough for basic rural needs. The solar modules power all lights, one small TV, small domestic appliances that are on occasionally such as a microwave oven and blender, and one refrigerator. All lamps are low-consumption units delivered by the solar manufacturer. The only refrigerator powered by the solar energy is at the main house and today we likely would purchase a solar refrigerator, which would be well-suited for this application.
The insolation at the fazenda is 5 kilowatt-hours per square meter per day, which is a fair amount of sunlight, making it a great place for a solar energy system. By comparison, Washington, DC receives around 4 kilowatt-hours per square meter per day of insolation.
Besides solar power, we use wood burning stoves for ambient heating and hot water in each house. Wood is easily available through a large renewable reforestation project in the community. The foreman’s and guest house’s refrigerators are powered by butane gas to save solar energy for other applications. The foreman’s house is backed by a gasoline power generator, which is used for running the washer, and to provide energy to the tool-shop, barn and horse stables when necessary.
How solar energy changed our lives
Clearly, the solar installation fulfills our basic needs, but not all. The initial set-up, installation and subsequent upgrades were relatively expensive when compared to hooking up to the distant grid from the onset. Why, then, install solar panels?
First, because we could not extend the grid to the property and we needed the electricity. Lights powered by kerosene are a hassle, exacerbated by the isolation of the fazenda—the closest grocery store is about an hour’s drive away. The size of the system was based on a monetary decision and on need: at the time, the system was large enough to provide the needed electricity, and the price of solar panels was much higher than it is today, making a bigger installation unnecessary. The wood-burning heating system is very efficient and did not need to be replaced.
Second, we believed it was our responsibility toward the environment and the community. The area is rural and poor, but a wave of German-Brazilians who came from São Paulo to escape the city in the 1970s brought with it economic activity and growth in education. The rural school in the Bom Jardim vicinity is based on the Waldorf philosophy, an Austrian philosophy called Anthroposophy, which aims to develop rational perception through the natural sciences and observations of the physical world. As such, members of the town are conscious about their responsibility towards the environment, which is why it was important for us to install an environmentally friendly source of electricity.
The system is small and, as the foreman’s family grows and prospers and more electrical appliances are introduced, it cannot fulfill all of the growing needs of the fazenda. With these concerns in mind, we are looking toward more solar and renewable energy solutions so that the foreman’s family and we may continue to live with modern conveniences.
For twelve years, solar energy has provided us with reliable electricity in the temperate rainforest in Brazil. Lack of infrastructure, a need for electricity and a desire to do the right thing toward the community convinced us to install solar energy in this rural and remote place…and the cherry on top is that we have never and will never receive an electricity bill in the mail.