On January 19th, Brazil opened the world’s first ethanol fueled power plant. Petrobras and General Electric Co (GE) upgraded a 45 MW turbine from Juiz de Fora, an originally natural gas fueled power plant, to be able to switch between natural gas and ethanol . The idea is to increase the clean power output from the plant. More than 80% of Brazil electricity comes from hydro plants but electricity provided by thermal plants is still needed to supply demand specially during dry seasons.
The first tests show that the change did not reduce the turbine potential, the CO2 emissions were below natural gas levels and less water was used . They believe that the use of ethanol for electricity generation can reduce the country nitrous oxide emissions by 30% compared to natural gas.
Although ethanol is still expensive compared to natural gas and the consumption is higher, it is still a good alternative for places without access to natural gas like Japan, some islands or places that depends highly on diesel like the Amazon region . GE has approximately 770 turbines around the world that could also be converted into flex turbines which might boost demand for ethanol .
The main concern related to increasing ethanol production is the need for more land to grow sugar cane. While looking for more information I found some critics about Brazil harvesting the Amazon to produce sugar cane. At first sight as a Brazilian I felt a little worried. But the sugarcane is produced in much larger quantity in the south and southeast of the country due to climate and soil conditions. The Amazon harvesting is a much more complex problem, that is mostly driven by illegal deforestation and lack of property rights, but they are not highly correlated with the sugar cane production.
One question that comes to mind is the energy gain of producing the ethanol and then using it to generate electricity compared to just burning the sun-dried bagasse. I could not find the answer, but I guess the biggest gain here is the possibility of switching existing thermal plants and reducing green house gases emissions. Also a couple years ago Brazil suffered with lack of natural gas supply and some of the natural gas power plants has to be turned off. So from an economic point of view this is an alternative way to produce electricity and reduce gas and oil dependence.