The building blocks of fuels
Hydrocarbons are organic compounds consisting only of hydrogen and carbon atoms, found in fossil fuels like crude oil, natural gas and coal. They are grouped into five main families or homologous series (alkanes, alkenes, alkynes, cycloalkanes, alkadiene). The hydrocarbons within a homologous series share a general formula, chemical and physical properties. The most recognizable hydrocarbons are those from the alkene family, like methane, ethane, propane and butane, which share a simple construction with carbon-carbon single bonds.
How combustion of hydrocarbons affects the environment
The combustion of hydrocarbon fuels releases carbon dioxide (CO2), as well as other greenhouse gases that contribute to atmospheric pollution and climate change. Unlike fossil fuel impurities that result in byproduct emissions, CO2 is an unavoidable result of hydrocarbon combustion. The energy density and CO2-footprint of a fuel depends on the hydrocarbon chain length and the complexity of its hydrocarbon molecules.
How incomplete combustion of hydrocarbons affects the environment
In addition to the effects of burned hydrocarbons, they are even more harmful when they escape in their unburned form. Toxic, carcinogenic molecules are found in engine exhaust, as well as evaporating petroleum and gas. Heavier forms can contaminate soil and groundwater. Methane, the hydrocarbon most frequently discussed in this context, is a more powerful heat-trapping greenhouse gas than CO2, so when it leaks into the atmosphere unburned, it contributes more to climate change than the carbon dioxide produced by burning it.
Harnessing hydrocarbon fuels more efficiently
Although a carbon-neutral future is a declared goal of the international community, eliminating hydrocarbon fuels from global power supply is a gradual, ongoing process. Cutting off all supplies of crude oil, gas and coal would be impossible, but we can do our best to minimize their harmful effects while working on the truly emission-free solutions of the future.
Combat the causes of global warming
Global warming is caused by the increased emissions from hydrocarbon fuels. Especially carbon dioxide accounts for about three quarters of greenhouse gases and mainly comes from burning such fossil fuels. Technology to reduce carbon dioxide emissions is available. Some of the most promising ones are described here.
Increasing efficiency from hydrocarbon fuels
One quick and efficient way of significantly reducing the impact of hydrocarbon combustion is to eliminate the least energy efficient fuel, that is also the worst pollutant - and replace it with a solution that is both cleaner and more efficient. Combined heat and power (CHP) plants are a very effective way to replace old and inefficient coal-powered plants. By converting waste heat to energy, they maximize every drop of fuel while serving a variety of thermal applications from industries to district heating. The German city Schwäbisch Hall shows how it can be done and relies heavily on CHP.
We’re making our energy system much more climate friendly, but we’ve been focusing too much on electricity alone. We have to realize that there are several other relevant areas, including transport, heat, and industry.