In evaluating the scenarios of sustainable and resilient energy transition in the isolated systems of the Amazon, some of the solar generators should be installed centrally to guarantee a central system of high performance, availability and reliability without clearing new forest areas, while another significant part of the generators should be installed in a distributed manner on rooftops and in agricultural projects.
In recent decades, attempts to reduce the involvement of diesel production in riverside and isolated Amazonian villages and towns have been unsuccessful. IPPs prefer to stick with the diesel generators they know so well, under the convenient cover designed decades ago to ensure energy availability, energy security and service reliability. Meanwhile, many renewable energy technologies (RETs) have experienced price reductions and established themselves in reliability and the use of locally available natural resources. In this context, RETs such as biomass, solar, and wind have been assessed to assist in the Amazon energy transition, and a comprehensive analysis is presented here.
Photo: ISES
Biomass: only a minority of communities in isolated systems have sufficient capacity to generate energy through biomass production from residues of the region’s main crops, including cassava, açaÃ, maize, banana and sweet potato. Energy production by burning wood residues obtained from sawmills with a sustainable management plan and international certification for the product is rare in the region, found only in one locality in the Amazon region (Itacoatiara – AM) (www.itacoatiara.com.br).
Wind: The Amazon region has a low average annual wind speed (less than 4 m/s), which, combined with the difficult accessibility and lack of scale of these isolated communities, makes wind energy production in the region competitive.
Solar power: Solar radiation resources are abundant and evenly distributed throughout the Amazon; The average annual global horizontal radiation is more than 1700 kWh/m2.year. Solar energy is a modular solution that is easy to install and requires little maintenance, but the technology has an important drawback, the need for a large area. There are three options for implementing solar power plants in the Amazon: i) centralized, ground-mounted solar power plants, ii) floating solar power plants, and iii) small distributed solar power systems (rooftop or ground, including agricultural power plants).
Photo: ISES
A major limitation of the large-scale, centralized ground-mounted option is the availability of suitable areas to install surface-intensive solar power plants without suppressing the forest. The Amazon rainforest is very dense with tall trees, and this is the biggest bottleneck for this technical solution, as many localities do not have clear areas of this magnitude. Agrivoltaics can play an important role in this, combining solar electricity production and sustainable land use.
Floating solar systems, which could be installed on river banks near which many isolated communities are located, are another option. Floating solar power is widely used in places with high population density and poor access to land, such as Singapore and Japan, and is typically installed in lakes or reservoirs, in calm water where water movement is only associated with local wind. The technical feasibility of installing floating solar power systems along the fast-flowing Amazon rivers is met with great opposition and skepticism among the major and experienced floating system manufacturers.
A third option for solar electricity production is the distributed rooftop solution, which is so commonly used in urban areas, and Brazil’s interconnected energy distribution system operates over 2 million installations. Analyzes by Brazil’s National Space Research Institute (INPE) show that the number of existing roofs in these isolated communities can guarantee a high percentage for these isolated systems. The option also has important social aspects, since the integration of solar power into multiple systems would require a considerable amount of local labor for installation and subsequent maintenance.
A typical dwelling in these low-income communities uses inexpensive fiber cement roof tiles installed on fragile wood structures that cannot withstand 20-25 kg/m2 additional load caused by a typical solar module + aluminum structure used in rooftop electricity. One of Brazil’s largest manufacturers of fiber cement roof tiles has developed fiber cement roof tiles to enable the integration of solar energy on roofs in these conditions, and they are in the final stages of durability and reliability testing at the Solar Energy Laboratory of the Universidade Federal de Santa Catarina. The additional weight of the 1/6 cut solar cell strips in the final roof tile is negligible, and replacing several of these solar cells on existing roofs is simple. Expected costs are below a traditional rooftop electric system, but scaling is necessary to obtain solar cells at competitive costs.
Photo: ISES
Photo: ISES
In this scenario evaluation of a sustainable and flexible energy transition in the isolated systems of the Amazon, some of the solar generators should be installed centrally to guarantee a central system of high performance, availability and reliability without clearing forest areas, while another significant part of the generators should be installed in a distributed manner on rooftops and in agricultural electricity systems.
Authors: Prof. Andrew Blakers /ANU) & Prof. Ricardo Rüther (UFSC).
Andrew.blakers@anu.edu.au and rruther@gmail.com
ISES, the International Solar Energy Society, is a UN-accredited member organization that was founded in 1954 and strives towards a world where 100% renewable energy is used efficiently and wisely for everyone.
