Workshop that gathered Brazilian and foreign experts to discuss the future of natural gas in Brazil and in the world reiterates the crucial role of gas in the coming years, especially for power generation.
The Sustainable Gas Research & Innovation Conference, which occurred on September 27 and 28 in São Paulo, left a clear message: natural gas concurrently represents a huge challenge and an incredible opportunity for Brazil. Our challenges include from the storing technology and the use of the resource (not only as an energy input, but also as feedstock for obtaining other resources, whose use technology is still under development), to the infrastructure for dissemination and transport, going through the demand creation and the lack of culture of gas use in Brazil.
In the meeting, Brazilian and foreign experts discussed the future of natural gas in a world scenario of reducing greenhouse gas (GHG) emissions and the rise in natural gas supply in the world, with the United States (USA) significantly increasing its shale gas production. The event was organized by the Research Centre for Gas Innovation (RCGI), from Brazil, and by the Sustainable Gas Institute (SGI), from England.
“Natural gas is a very important part of the energy system and its uses for obtaining energy have been growing. Hence, in the short and medium term, it very clearly plays a highly important role. Beyond the medium term, there are questions regarding the carbon footprint of gas, seeing that it is fossil, even being much cleaner than many other fossil fuels, such as coal. The questions academics currently ask themselves regard how, why, where and when we should keep using it, to ensure a sustainable and safe energy system,” sums Nigel Brandon, SGI director and a professor with the Imperial College London, who opened the conference.
Judging from the abundance of reserves, gas is likely to keep its upward supply curve, led by the EUA, where production keeps increasing (and where there is a pressure for reducing the use of coal, particularly in the energy sector). “There is plenty of natural gas in the US. The more we search, the more we find. Prices are endogenous and never rise, because production keeps growing. They are expected to fall even more, since there is a large amount of natural gas in the world: Canada has it, Mexico has it, and the south cone of Argentina has it, Brazil has it, Bolivia has it…,” says David Daniels, Chief Energy Modeller of the North American EIA (Energy Information Administration).
He deems the future of the Brazilian gas is not certainly exportation. “It is very difficult and expensive to transport natural gas in vessels. For an idea, transporting oil by ship throughout the world costs about US$ 2 per barrel. Transporting gas may reach US$ 10 per MMBTU. I believe that, in Brazil, the great issue regards the demand: what will the demand for natural gas be, what will the demand for oil be? Both in Brazil and in the world. This is the question here.”
CO2 emissions – According to Nigel Brandon, when looking ahead, it is necessary to think of technologies that reduce the carbon footprint of natural gas, such as Carbon Capture and Storage (CCS). “We have studies stating that if we do not use CCS, we will not be able to use a large share of the fossil resources of the planet and, at the same time, reach the emission reduction goals. There are other possibilities: we can opt for not using fossil fuels. But, if we use them, we have to resort to CCS. The technology is available, it is viable, has already been used, but its costs have to be reduced. Shell has been working intensely on that, as we verified,” he states, referring to the presentation by Rob Littel, General Manager Gas Separation with Shell, who showed different initiatives for separating CO2 and other processes to transform it, in the event.
For Littel, it is too early to say that CCS is the technology with greater possibilities of being disseminated. “We are looking at all the candidate technologies [to help us with the emission issue] as alternatives. We put energy on them and we compromise with developing them as fast as possible, and at the same time, we are very open to other disruptive technologies. If there is a better technology, we will be there! We will be glad to change the course.”
For Rita Maria Alves, a Professor with the Escola Politécnica (School of Engineering) of the University of São Paulo (Poli-USP) and vice-coordinator of the RCGI physics-chemistry program, CCS is one of the possible technologies, but large organizations are already investigating how to transform this CO2 into value-added products, instead of storing it underground. “About four, five years ago, there was a large amount of research into CCS and it is actually one of the ways. But trends show that large companies in the chemical sector, such as Bayer, are already using CO2 to produce polyurethane. I believe this is the trend from now onwards.”
Methane slips – Another challenge for scientists regarding the use of natural gas are the methane leaks. Natural gas is mainly composed of methane, a greenhouse gas generator, twenty times as harmful as carbon dioxide. In the US, where natural gas has been intensively used to generate power as a replacement to coal, helping to reduce the energy carbon footprint, the challenge of leaks is still of great concern to scientists and to the instances involved in the product chain.
“If 1% to 3% of the gas we extract from the ground leaks before we use it, then we lose all the advantage it has as allow-carbon fuel,” sums Dave Allen, a chemistry engineering professor with the University of Texas, in Austin (EUA). According to him, an average estimation for the US suggests a 2% slip of all the gas extracted. “That is, we have already lost a great share of this advantage. The average does not tell the whole story. What we have is a situation in which a small share of the installations accounts for a large share of the emissions. We call them super emitters.”
For this, he and a group of scientists is involved in finding the super methane emitters. “Finding these super emitters is a great technological problem. Of all the installation using gas, how can we track all the methane leaks? This requires technology and there is a large amount of ongoing research in the US to deal with this task.”
Professor José Carlos Mierzwa, with Poli-USP, remarks that currently 60% of the methane emissions are caused by leaks in turbines and pneumatic devices. He coordinates one of the RCGI projects, which uses topological optimisation of labyrinth joints to prevent leaks in these devices, used for sealing rotating parts subjected to high temperatures.
“With the growing demands for low pollutant emissions and for the need of more efficient equipment, the leaks in the labyrinth joints become increasingly more critical. Hence, we decided to develop a labyrinth joint design methodology so as to minimise the leaks.”
Solutions – Júlio Meneghini, Director of the RCGI, highlights that the Centre works on projects that account for a large share of the technological, market, logistic and cultural challenges involving the use of natural gas, such as hydrogen, as well as ways of mitigating the emissions of CO2 and of other gases contributing to the greenhouse effect in Brazil and at a global scale. “In our twenty-nine projects, we have investigated from state of the art themes, such as separating CO2 from natural gas by means of membranes and supersonic separators, up to new combustion technologies, the performance of which should have a smaller impact on the environment. We have also investigated transforming natural gas into plastic by a biological route; the potentialities of the use of gas by the industry and by the residential sector; its use as fuel for vessels; the optimisation of tanks for transporting the gas adsorbed in activated coal; the development of fuel cells that operate with natural gas and also with hydrogen produced from it; the elasticity of gas prices as compared to those of other energy inputs, among other topics. We are investigating a wide range of technologies, methodologies and processes.”
Rob Littel, from Shell, highlights that the technologies are getting increasingly more expensive and it is necessary to be selective when choosing investments. “But we have to be clever regarding this selection. Challenges are opportunities. The more we make the right choices, the more opportunities we will have of addressing the problems we need to solve.”
He defines the energy matrix as a puzzle, and natural gas as part of this puzzle. “It could help constraining CO2 emissions. But it is not the answer to the whole puzzle, which requires a mix of solutions.” The Shell representative calls attention to the immense amount of gas associated to oil in the Brazilian pre-salt. “It is an opportunity for Brazil, provided we can separate the CO2. And, with this opportunity, Brazil fits another piece of its puzzle.”
For Daniels, from the EIA, the SGI and the RCGI have been doing a great job towards helping to assemble this puzzle. “I very much like the idea that, supported by the USP, the RCGI provides the natural gas sector with the modelling experience engineers count on. I like this combination, once it allows us to understand problems from the point of view of engineering, and thus understand the system and its impacts. This arrangement is very rare. There are a number of organisations, including the EIA, observing the dynamic of the systems. But there isn’t such an approach from engineering, which is very important.”