Planes Could Soon Run on Garbage

There were discussions, for the first time ever, about the social justice costs of transitioning to a sustainable economy, which requires the extraction of minerals, like cobalt and lithium, that are used in making solar panels, wind turbines, and electric vehicles. As Climate Home News reports, the increase in mining activity has driven deforestation and environmental destruction not to mention human exploitation. At the end of last week, the conference was considering a proposed document on a fair conversion to clean energy, the "Just Transition Work Programme."

No representatives were sent to COP30 by the U.S. government; nevertheless, delegations of American governors and mayors are there. Senator Sheldon Whitehouse (D-Rhode Island) went at the end of last week with a goal of showing that the American public still broadly supports addressing climate change even though Trump does not. 

While the Trump administration dismantles efforts to combat climate change, China is rapidly reshaping the global approach to energy. The Economist reports that the extent of the renewable energy revolution in the country is “nearly too much for the human mind to grasp.”

By the end of 2024, China had installed almost twice the solar capacity of the U.S. and Europe combined, and it produces as much renewable energy as more than 300 large nuclear plants. Additionally, China is making more money from exporting its green technology than the U.S. does from exporting fossil fuels. Still, China is the largest producer of climate warming CO2 emissions; and as those levels have plateaued, emissions in the U.S. and Europe have risen significantly.

Because the Lower Basin states of Arizona, California, and Nevada, and the Upper Basin states of Utah, Wyoming, New Mexico, and Colorado cannot agree, it is likely that the federal government, through the Bureau of Reclamation, will impose a plan that could mandate water cuts. Any plan from the bureau will have to go through a public comment period and an environmental review process. Thirty tribal governments are entitled to about one-quarter of the water in the river and must be involved in coming to an agreement.

As the deadline passed, there were two differing views leading to disagreement between the basins. Becky Mitchell representing Colorado, one of the four Upper Basin states, said at a conference that they would resist any cutback in their water allocation. On the other side, Arizona governor Katie Hobbs wrote in a letter to the Interior Department that it must impose cuts on the Upper Basin states. Mitchell said that she is still optimistic that the seven states could reach a consensus.

A team from the University of Stirling in Scotland studied wetlands made by beavers and found they had a higher number of hoverflies and butterflies when compared to human-built ponds. Pollinator populations are plummeting worldwide from habitat loss, climate change, and pesticides, so the finding that beavers—nature's foremost ecological engineers—can build supportive environments for insects is welcome news.

The increase in hoverflies is particularly important because, according to the Wildlife Trusts in the UK, they are the unsung heroes of many ecosystems as the second most significant pollinator after bees, with some species visiting more flowers than bees. Hoverflies also protect plants from aphids, are food for birds, and even help break down organic matter in gardens. 

Beavers create habitat for hoverflies and other insects by randomly felling trees and grazing on herbaceous vegetation. Eager beavers boost biodiversity by continuously modifying both aquatic and terrestrial environments to keep soils moist, which provides ideal breeding conditions for insects. The authors say beaver wetlands can now be seen as a valuable and scalable tool to help reverse the decline of pollinators.

The study was published in the Journal of Applied Ecology. 

A solution may be ready to take off. Researchers at the Harvard-China Project on Energy, Economy, and Environment and Tsinghua University in China say planes could soon run on garbage. They found that our trash—from food and plastics to paper and metals—can be converted into a sustainable aviation fuel that emits less carbon. Sustainable aviation fuels, which are currently derived from cooking oils or crops, have been slow to get off the ground, making up less than one percent of global jet fuels because of high production costs and low supply.

The team studied converting solid waste into jet fuel through gasification and Fischer-Tropsch synthesis and say the potential is sky high. They found, in a lifecycle analysis, that the fuel could reduce greenhouse gas emissions by 80-90 percent compared with conventional jet fuel. This waste-based fuel would help reduce methane emissions and decrease water and air pollution by sending less garbage to landfills. Sustainable aviation fuel could also help cities move toward zero-waste goals.

The study examined how municipal solid waste could be converted into sustainable aviation fuel under several scenarios and found, in the most practical case, global municipal solid waste could yield around 50 million tons and cut aviation’s greenhouse gas emissions by around 16 percent. If green hydrogen were integrated into the process, it could supply up to 28 percent of global jet fuel demand and reduce emissions by as much as 270 million tons of carbon dioxide annually.

The main headwind would be scaling up gasification systems worldwide, and that would require investment and coordination by governments, airlines, fuel producers, and aircraft manufacturers to develop policies around waste collections and sorting, as well as the siting of gasification plants. However, the waste-based, low-carbon fuel can work in today’s engines, so cutting emissions can start immediately for an on-time departure.

The study was published in Nature Sustainability.