Chemistry 2210A/B Lecture 7: Chapter 7 - Biofuels and Alternatives

• School: Western University
• Department: Chemistry
• Course: Chemistry 2210A/B
• Professor: Kay Calvin

Document Summary

Biofuels use contemporary photosynthetic mass indirect forms of solar energy: contemporary photosynthetic mass = recently produced. Liquids at normal temperatures and release lots of heat when burned. But they do contain carbon: burning results in co2. Power density of photosynthesis too low for the world"s energy needs. Process of photosynthesis not very efficient: conversion of sunlight into plant material, which eventually results in chemical energy (indirect process) The other side : clearing land, fuel used to clear land, controversy about growing crops for fuel and not food, conversion of biomass to biofuels, lots of energy required, no savings in co2 if fossil fuels are used. Payback period : number of years needed to repay the carbon debt from using biofuels. Easily blended with gasoline: gasoline mixes designated by an e numbering system. E85 also available, but engine must be designed for this fuel: flex fuel runs on regular fuel as well as e85.