Fossil fuels are non-renewable. They took a very long time to form and we are using them up faster than they can be replaced - once they have all been used up, they cannot be replaced.
Fossil fuels are also finite resources. They are no longer being made or are being made extremely slowly. Millions of years ago, huge numbers of microscopic animals and plants - plankton - died and fell to the bottom of the sea. Their remains were covered by mud. This can slow growth rates, weaken shells, and imperil entire food chains. Ocean acidification impacts coastal communities as well.
State and federal incentives, along with falling prices, are pushing our nation —and the world —toward cleaner, renewable energy sources such as wind and solar. Renewables are on track to become a cheaper source of energy than fossil fuels, which is spurring a boom in clean energy development and jobs.
Significantly higher levels of renewables can be integrated into our existing grid, though care must be taken to site and build renewable energy responsibly. It accounts for more than 2. If we can put the right policies in place, we are poised to make dramatic progress toward a clean energy future. To do that, we will need to cut energy demand in half, grow renewable energy resources so that they provide at least 80 percent of our power, electrify almost all forms of transportation, and get fossil fuels out of our buildings.
That will require sustained, coordinated policy efforts from all levels of government, the private sector, and local communities. But we know we can do it using the proven, demonstrated clean energy technologies that we have today. Distrust in the TVA runs deep in eastern Tennessee, and as the utility shutters two power plants—Bull Run and Kingston—local activists fear it will close up shop without safely containing its leaky pits of toxic sludge and ash. Limetree Bay oil refinery recently announced its indefinite closure.
The global toll of premature deaths attributed to the burning of coal, gasoline, and diesel is breathtakingly high, with new research doubling previous estimates. As the country focuses on fighting a pandemic and mourning its victims, the Trump administration sees a perfect time for showering the fossil fuel industry with gifts.
Oil and gas operations leak this potent greenhouse gas far more than previously thought, and par for the course the Trump administration is making the situation worse. Some people tout bioenergy as a solution to our climate crisis. Hydraulic fracturing has upended the global energy landscape and made fossil fuels big business in the United States. Mounting evidence shows that it poses serious threats to our health, environment, and climate future.
In Texas, tax breaks for fossil fuels outpace tax breaks for renewables by a rate of two to one. Guess which sector is whining about unfairness? After an illegal dumping of close to 2, tons of dangerous sludge and contaminated materials across the street from two schools, a Kentucky community struggles with what to do next. As the interior secretary ponders the fates of 27 national monuments, he seems to be hearing some voices more acutely than others.
Our rivers, reservoirs, lakes, and seas are drowning in chemicals, waste, plastic, and other pollutants. Healing the planet starts at home—in your garage, in your kitchen, and at your dining-room table. Activists across the country rallied, hosted listening sessions, and submitted public comments to advocate for carbon pollution limits from power plants. The United States and Mexico meet the deadline for their carbon pollution goals.
Will others follow? In what the modern world sees as coal and oil, this New Yorker sees ancient plant species—and hope. The president wants to relax national fuel efficiency standards and bully states into scuttling their own plans for lower emissions and cleaner air.
We will keep you informed with the latest alerts and progress reports. Greenhouse Effect This can take awhile, especially for very tough or woody plants, but adding GVL to the reaction gives the acids a big energy boost.
This boost helps the system gather its activation energy faster, so the reaction can proceed more quickly 4 , 5 Figure 3. To illustrate this phenomenon, imagine that two girls, Gemma and Valerie, are about to race each other to the top of a steep hill. Usually, both runners must stand behind a starting line to make sure that the race is fair. But in this race, Gemma is actually allowed a big head start: when the buzzer goes off, she gets to start running halfway up the steep hill, while Valerie must begin from the very bottom.
Who do you think will win? You guessed it — Gemma gets to the top of the hill way before Valerie. Just as the head start puts Gemma closer to the top of the hill in the race analogy, GVL brings the acid closer to the point of reacting with the biomass, allowing the reaction to proceed much faster. To plants, lignin is really important: it gives them their shape and structure, and helps them grow healthy and strong.
But to scientists, lignin is just a nuisance. It is a tough and stubborn molecule that is very hard to break down, and it interferes with obtaining simple sugars from cellulose and hemicellulose molecules. One day, scientist hope to be able to break down lignin itself to make useful things, but for now, they just want it out of the way.
GVL has the unusual ability to dissolve lignin, and to keep it from blocking the big prize: the energy-rich sugar building blocks. Perhaps, the best thing about it GVL that it is can be recycled.
At the end of a biofuel reaction, liquid CO 2 can be added to the reactor to separate each reactant into a distinct layer Figure 2. Think of a bottle of fancy salad dressing: the oil and vinegar, instead of mixing with each other, stay completely separate until the bottle is shaken. Likewise, when CO 2 is added to the biofuel reactor, the GVL and sugar solution become just like that salad dressing.
The sugars all move into one layer and become concentrated see Figure 2 , while the GVL forms its own separate layer. The GVL can then be easily removed and used again, while the sugar solution that scientists end up with is around five times more concentrated than it would be without GVL.
This increased concentration is very important, because it means that you need to spend less energy purifying the final product, making the whole process more efficient and less wasteful. After the GVL has been removed, a concentrated — and very useful — sugar solution is left behind. Scientists have two options for using this energy-rich solution:.
For all these reasons, using GVL gives scientists hope for creating biofuels and chemicals that can compete with petroleum products in the marketplace. For centuries now, humans have been inventing new technologies and developing industry at an astounding rate — sometimes at a serious cost to the environment.
A biofuel production process that meets all the requirements of affordability, renewability, and sustainability has the potential to benefit both humans and the earth. With the discovery of GVLs role in biofuel processing, we believe that we are one step closer to a sustainable future.
Some biofuels can provide renewable alternatives to fossil fuels, such as gasoline. Plant biomass is made up of three main molecules: cellulose, hemicellulose, and lignin. Types of biomass used for biofuels include plants and plant wastes, such as grasses, corn stalks, and wood chips.
Fossil fuels include coal, natural gas, and petroleum. Petroleum can be refined into other fuels, such as diesel and gasoline. This phenomenon is called the greenhouse effect, and it can lead to an overall increase in global temperatures called global warming.
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