Inflation is jacking up prices at the pumps because of the squeeze on global oil supplies. The world is still dependent on fossil fuels despite the recent fall in petrol prices.
It's also a sign that fuels are getting some attention. Blending corn-ethanol into petrol saves consumers money and creates jobs in the farming communities that supply its distilleries, according to the industry.
The refining industry is expanding as fast as it can. Some biorefineries are designed to process palm, soya and Canola oils, while others are adding vegetable oils and animal fat to their fuels. The refinery in Rodeo, California, will be converted to solely process bio-feedstocks. US refinery expansions that have been announced could increase demand for soya bean oil beyond the country's total supply. If filling fuel tanks with these plant-derived liquids reduces carbon emissions by decreasing the demand for fossil fuels, it would help to tackle the changing climate.
It seems obvious that the sustainable use of fuels is possible. Vehicles burn the fuel they produce and the carbon cycle in and out of the atmosphere. The industry has been battered by a constant flow of reports on the benefits of bio fuels. Fossil fuels seem to be better for the climate than the first generation of fuels. The programme, which requires that transportation fuel contain a minimum volume of renewable fuel, and which drives nearly half of global biofuel production, has probably increased greenhouse-gas emissions. Farm operations using diesel and natural gas resulted in that outcome. Nitrogen oxide is a greenhouse gas that is more potent than carbon dioxide. Farm soils can release carbon that is needed for resilience and fertility.
Worse still, the increase in demand for biofuel crops has extended farming onto marginal lands, damaged biodiversity and increased water use andContamination, as well as pushed up the price of agricultural commodities and thus exacerbated food security. The authors of the assessment conclude that the US programme will be sustainable if there are more discoveries.
Scientists agree on carbon emission life-cycle. Farmers need to pay close attention to what crops work best where and how they are grown. Reducing tilling of the soil can retain carbon and nutrition. Winter oilseeds that can be grown between food-crop rotation can also be planted. Revenues from this could be used to pay for a practice that many farmers have yet to embrace.
Crop coverage is less than 2% of the land. The process of growing a crop to protect and improve the soil can be used to make biofuel if you go to 40– 50%. At Nuseed's research centre near Sacramento, California, there is a regulatory and sustainable programme led by Johnston.
The new era of fuels still has environmental concerns. According to researchers, regulation needs to be improved to make sure that the industry is sustainable. Tracking carbon can be a lot of work. If you get it wrong, biorefineries could end up being a panacea for the environment.
Ten years ago, the transition to better fuels seemed imminent. There was a new generation of biorefineries coming online. They were designed to make the fuel from sources that thrive on marginal farmlands, such as agricultural leftovers, grasses, and fast-growing trees. By now, these renewable fuels made from sustainable sources were supposed to be making their way into the fuels market.
The flow of fuel isn't very high. The equipment used to process fuels proved hard to use, petrol prices fell and mandates to force higher-priced fuels into the market were relaxed. All of those facilities didn't work out. John Field, who studies the climate-mitigation potential of bioenergy systems at Oak Ridge National Laboratory in Tennessee, said that most are either producing at very low levels or not producing at all.
The generous incentives pushed food-based fuels and their weaknesses. Europe's renewable energy directive led to logging and burning of tropical rainforests in Brazil, Indonesia and elsewhere to make way for soya bean and oil palm plantations. As the soil warms and dries, more carbon can be released from it. Roughly three-quarters of Earth's organic carbon can be found in soil.
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Ben Lilliston is the director of rural strategies and climate change at the Institute for Agriculture and Trade Policy. Carbon stored in forests and farm soils can be released in ways that regulators can't account for. US biorefineries have bought a growing share of US soya bean harvests. Soyal bean producers in other countries scale up to meet US soya demands.
Carbon debt may never be repaid. The carbon intensity of palm oil-derived fuels is triple that of petroleum fuels if land use impacts are taken into account.
The opportunity cost of farming to supply biorefineries is due to the fact that restoring the same land to forest or native grasses would offer greater carbon reduction. Tim Searcher is the technical director of the food programme at the Center for Policy Research on Energy and the Environment in New Jersey.
The land-use and life-cycle studies required to account for a biofuel's carbon footprint are complex and expensive. It is difficult to find reliable data. The amount of soil carbon varies greatly. Sampling can take up to 10 years to detect changes in soil carbon. Rebecca Rowe is a researcher at the Centre for Ecology and Hydrology in Lancaster, UK.
The director for sustainable international transport based in London at the Environmental Defense Fund says that assessing the sustainable use of fuels is difficult. He says that it becomes crazy very fast. Tools and methods exist to reliably cut through the complexity, and these will show that some fuels do reduce carbon emissions. There are methods that can be used to make sure that alternatives to aviation fossil fuels have high integrity.
The analysis will show that the production of biofuels can be sustainable. He is not optimistic about their economic viability due to an emerging challenge from another class of alternative fuels. The cost of avoiding a ton of CO2 emissions through the use of electrical fuel will fall to about $70 in the next 10 years, according to a report. The cost of cutting a tonne of carbon is likely to go up.
Competition for finite land is the ultimate dilemma regarding the use of renewable fuels. The World Resources Institute, a think tank in Washington DC, says there will be a gap between food calories produced in 2010 and those needed in the future. A reduction in agricultural land use is required in most of the pathways that limit global warming. Janet Ranganathan, who studies environmental accounting and technology and oversees research at the World Resources Institute, says that expansion of biofuel production will inevitably drive up food prices and make it harder for people to eat. She doesn't believe that future advances can be more than a niche role for biofuels.
Researchers are still working to improve the sustainable use of fuels. Rowe is helping the UK government to expand the planting of bioenergy crops from close to nothing to about 3% of the UK's land area.
According to Field's research, biofuels have the potential to be more than just a bad thing. In a 2020 paper, he and his colleagues showed that under certain conditions, it is possible to surpass the benefits of climate restoration with the use of renewable fuels. Land use transitioning from food crops to switchgrass was the best example of this. Field and his co-authors estimated that the carbon mitigated potential was similar to that of reforestation. If crop yields and bioprocessing technologies can be improved, and if CO2 from biorefineries can be permanently sequestered deep underground, the researchers predict that supplying cellulosic feedstocks could store up to four times more carbon than does. These are areas where there is a lot of research and development attention.
The US Inflation Reduction Act that was passed in August gives tax breaks to companies that develop CO2 lines. Farmers whose land may be in the path of the project face a lot of resistance.
Miscanthus is a crop similar to switchgrass that is the preferred option for the UK bioenergy crop scale-up. According to the UK government, these crops will help to cut emissions from biorefineries by the end of the century. Rowe says that the key is to use the lessons learned from the development of fuels to find the most sustainable places to grow. It usually means avoiding high-carbon soils such as peatlands.
The cover crops in development seem to be a good response to arguments against dedicating land to the production of fuels. The soil in the fields is prone to erosion by wind and rain. A cover crop creates channels that allow water to sink into the soil instead of draining it. Oilseed cover crops can pay for themselves by producing oils that can be used in biorefineries.
Nuseed's crop carinata is derived from Brassica carinata, a tall cousin of rapeseed. Carinata has 2.5 times more oil than soya beans, which is the main crop for renewable diesel. He says that carinata doesn't compete with food supplies or cause climate harm. Although land-use effects add an extra 4–26 grams of CO2 emissions per megajoule of energy delivered from soya-based fuels, carinata cuts 7–13 grams of emissions per megajoule from fuels. "Land-use change goes from being a highly uncertain but potentially large liability to having a small but positive effect."
A report by Field and his colleagues shows that carinata could be used in a major industry. A few percent of US cropland is Simulating application of carinata every third year. About a billion litres of aviation fuel can be made from that seed.
Nuseed has begun planting in Argentina and is sending oilseed to Saipol to make millions of liters of renewable fuel. By the end of this year, Nuseed will expand to the southeastern United States and Brazil. It plans to scale up quickly, aided by a ten-year supply and market-development deal with energy giant BP, and to be supporting billions of litres of fuel production per year by 2030.
It is necessary for carinata to occupy a larger role in the scene. He says that government programmes don't recognize and reward the crop's benefits.
The refineries that sell soya-derived fuels to California don't have to pay a penalty for the soil carbon loss caused by industrial farming practices. California and other states aren't fast enough for oilseed cover crop developers.
The markets for offsetting carbon are poorly regulated and could give regenerative agriculture a bad name. Farmers who adopt carbon-friendly practices will be paid for their efforts. Most of the offsets are purchased by corporations to claim progress towards emission reduction pledges.
There are pitfalls associated with carbon accounting that offset markets often ignore. Research shows that reliable accounting requires sampling across a crop's full root zone, which could extend down to onemetre or more, despite the fact that soil sampling needs to go to a depth of only 30 centimetres. It might not be clear if carbon stores have risen or fallen, because some markets allow contracts requiring farmers to maintain climate-positive practices for as little as five years.
The benefits of soil carbon offsets could turn out to be illusory and undermine the integrity of net zero targets. Lobbying for weaker rules could be encouraged by these offsets. The people buying up cheap soil carbon offsets with questionable accounting methodologies have a vested interest in making sure that tomorrow's regulations don't destroy their offsets' value.
The markets may help perpetuate the culture that dominates agriculture today. Farmers depend on fossil-fuel providers for products such as fuel, and they struggle to make ends meet because they capture most of agriculture's economic value. If farmers use offset programmes to recover the value of their crop production, the balance could tilt further.
A system thatcirculates both natural and economic resources to create a more sustainable and resilient system is what advocates for farming communities would like to see.
It's a big ask to ground up agriculture. One has to wonder if another next- generation biofuels failure isn't the more likely outcome if the sustainable nature of the fuels depends on fundamental changes.
The article is part of Nature Outlook: Circular Economy.
The paper was written by T. J. The National Acad. It's a science USA 118, e1084119
The authors are H., Lee, U., and Wang. It's called ener. There is a Rev. 134 and a Rev. 112.
Field, J. L. The National Acad. It's a science USA 117, 21968–2 1977
J. L. and his associates front. The Energy Res. 10 was published in the year 2000.
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