Watts Up With That? By Andy May 3/13/2020
According to Exxon-Mobil, 9% of the world’s energy came from biofuels in 2017. They do not expect this percentage to increase by 2040, and it may go down. For the most part it is a developing world fuel. Primary biofuels include dung, wood, wood chips and pellets. Secondary, or manufactured biofuels include ethanol and biodiesel, which derive from several agricultural products, mainly corn, sugar cane, palm oil, soybeans and canola. The main advantage of using locally sourced wood and dung are their low cost and wide availability. Using imported wood or wood chips for generating electricity, as is done in Europe, is more problematic. Due to the economic and environmental costs of farming the trees, making the wood pellets or chips and shipping them to the powerplants; wood is not a competitive fuel for most powerplants. The energy density is too low. However, if the source of the wood is within fifty miles of the plant, it can be competitive with coal and it may produce fewer greenhouse gases than coal, estimates vary. Ethanol and biodiesel are also more expensive than fossil fuels and must be subsidized to be competitive.
Worldwide, biofuels (meaning biomass + transportation biofuels + waste) are the largest renewable energy source. In 2017, bioenergy accounted for 60 to 70% of renewable energy consumption. In the same year, biofuels supplied about three percent of the energy used in transportation, this was mainly biodiesel and ethanol. Worldwide, about 95% of the renewable energy used for heating and cooking in the home, on farms, in restaurants and by street vendors, was from burning dung or wood. This causes considerable indoor air pollution and the World Health Organization (WHO) estimates some four million people die every year as a result. In 2017, 86% of the biomass, burned for energy, was used for cooking or heating homes, most of the remainder was ethanol or biodiesel.
Ethanol, biodiesel and wood as fuel: The economicsBiofuels have a low to very low energy density, relative to fossil fuels or nuclear fuel, and you need lot of biomass to produce much energy. Biofuels, with the exception of some biodiesel products, also cause a lot of pollution, this includes the pollution created when growing the product, such as wood, palm trees, soybeans, canola or corn; the pollution created when ethanol or biodiesel are manufactured; and when the product is burned. An external cost of biofuels is that using them can raise the cost of food, this is particularly true of corn ethanol. Another external cost is that producing, and manufacturing biofuels uses a lot of water and water availability is a problem in many parts of the world.
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https://wattsupwiththat.com/2020/03/13/biofuels/