This is a short guide outlining:
– which energy sources might be the most dangerous
– and which might be the safest
Summary – Most Dangerous/Harmful, & Safest Energy Sources
Danger and harm from different energy sources can come in several forms – disease health problems, diseases/illness, death, or the increased risk of harm one way or another
Energy sources can cause danger or harm in various ways such as the emission of air contaminants leading to air pollution (and poor air quality), and greenhouse gas emissions leading to climate change and global warming – just as two major examples
*It’s important to note that energy sources being used in different geographic locations might pose different levels of harm.
Just one example is a coal plant using air pollutant catching technology in one city vs another city that doesn’t use this technology.
It’s also important to note that an energy source might be harmful in a particular area due to the volume of that energy source being burnt, but, that energy source might be much safer if burnt in smaller quantities.
For example, huge population dense cities may just emit far more volume of air contaminants due to fossil fuel burning compared to smaller less population dense cities.
*Also, it’s important to date that whilst a fuel source may be ‘harmful’ in one sense, it may also be beneficial in another by providing cheap electricity, providing jobs and helping grow economies.
There’s also some question over deaths and conditions attributable to air pollution from fossil fuels like coal.
Some argue that it’s too difficult to separate pre existing conditions and the impact of air pollution caused by coal power plants, or even smog from vehicles.
In addition, some reports even claim that pollution from fossil fuels is overstated or over exaggerated in some cities and regions.
Deaths Caused By Different Energy Sources Per X Amount Of Electricity Produced
Deaths per 1000 TWh (tera watt hours) generated are:
Coal – 100,000 (deaths per 1000 TWh produced)
Oil – 36,000
Gas – 4000
Hydro – 1400 (skewed by Banqiao dam collapse)
Solar (rooftop solar only) – 440
Wind – 150
Nuclear – 90 (includes nuclear power plant incidents like Chernobyl and Fukushima. In 2018, nuclear provides about 11% of the world’s electricity from about 450 power reactors, generating about 2,500 TWh of electricity each year)
Energy Sources & Air Pollution
The rate of short-term deaths from accidents and air pollution related to energy production, standardised to the deaths resultant from the production of one terawatt-hour (TWh) of energy are:
Brown Coal – 32.72 (deaths per terawatt hour produced)
Coal – 24.62
Oil – 18.43
Biomass – 4.63
Gas – 2.82
Nuclear – 0.07
Air-pollution related deaths are dominant [in the above data].
In the case of brown coal, coal, oil and gas, they account for greater than 99% of deaths, as well as 70% of nuclear-related deaths, and all biomass-related deaths.
Cancer from radioactive exposure is also taken into account in the above data.
*Note – One terawatt-hour is roughly equivalent to the annual energy consumption of 12,400 US citizens
Hypothetically, if all energy production in the world was met through one energy source in 2014, the number of deaths from each energy source might have been:
Brown Coal – 5.3 million (deaths)
Coal – 3.91 million
Oil – 2.93 million
Biomass – 736,170
Gas – 448,539
Nuclear – 11,776
Other Notes On Energy Sources & Air Pollution
Coal-fired power plants are a key source of sulphur dioxide and nitrogen oxides, key precursors to ozone and particulate matter (PM) pollution (ourworldindata.org)
Air pollution in kills 4,400 people daily in China alone (visualcapitalist.com)
Energy Sources, Greenhouse Gas Emissions & Impact On Climate Change/Global Warming
Energy consumption is one of the main activities that emits greenhouse gases.
There’s a few different ways to measure and track greenhouse gas emissions from different energy sources, such as:
– total emissions from each energy source
– emissions, in kg of CO2, per Mega watt hour of electricity produced
– emissions during the lifecycle of the energy source e.g. from manufacture, the set up, to operation, to decommissioning and waste
Total emissions from each energy source
Globally, annual per year C02 emissions by fuel source, measured in billions of tonnes per year, in 2013, are:
Solid Fuel (Coal) – 15.15 (Bt)
Liquid (Oil) – 11.79
Gas (Natural Gas) – 6.62
Cement Production – 2.03
Gas Flaring – 249.36 (Millions of tonnes)
Note, that each country differs with the energy sources that emit the most greenhouse gases.
Different sectors also have different dominant gases that are emitted.
Emissions, in kg of CO2, per Mega watt hour of electricity produced
Carbon dioxide emissions, in kg of CO2 produced per mega watt hour, are:
Charcoal – 403.2 kg CO2
Coke – 385.2 kg CO2
Oil Shale and Tar Sands – 385.2 kg CO2
Peat – 381.6 kg CO2
Lignite – 363.6 kg CO2
Anthracite – 353.88 kg CO2
Sub Bituminous Coal – 345.96 kg CO2
Bitumen – 290.52 kg CO2
Diesel Oil – 266.76 kg CO2
Crude Oil – 263.88 kg CO2
Shale Oil – 263.88 kg CO2
Aviation Gasoline – 252 kg CO2
Jet Gasoline – 252 kg CO2
Motor Gasoline – 249.48 kg CO2
Natural Gas – 201.96 kg CO2
Emissions during the lifecycle of the energy source
The Life cycle CO2 equivalent (including albedo effect) from selected electricity supply technologies .. arranged by gCO2eq per kWh (CO2 equivalent per kilowatt hour of electricity supplied) in median values … are:
Coal – 820 (median gCO2eq per kWh)
Biomass (co-firing with coal) – 740
Gas (combined cycle) – 490
Biomass (dedicated) – 230
Solar PV (utility scale) – 48
Solar PV (rooftop) – 41
Geothermal – 38
Concentrated Solar Power – 27
Hydropower – 24
Wind Offshore – 12
Nuclear – 12
Wind Onshore – 11
Another note to make is that sometimes natural gas GHG emission calculations do not include the leakage of methane when it is extracted.
Some sources note that the carbon footprint of natural gas can be similar to coal in some instances when this is taken into account, as opposed to just the burning of both fuel sources.
Other Factors To Consider When Assessing Danger & Safety Of Different Energy Sources
Deaths associated with mining fuel resources e.g. coal and oil mining
How waste is treated, managed and disposed of – particularly radioactive and nuclear waste
Operational accidents at power plants e.g. nuclear explosions and associated radioactive exposure for years after, dam collapses for hydroelectricity
Indirect harm from factors such as water pollution (caused indirectly by acid rain – which air contaminants from fossil fuel power plants and petroleum and diesel vehicles contribute to). In addition to water pollution, there can be other environmental issues that arise indirectly from the use of fossil fuels that can ultimately negatively impact humans
theguardian.com echoes the above results:
In terms of raw numbers of deaths, coal is the most dangerous source of energy for workers
In terms of deaths by energy output, coal is probably the most dangerous
Coal kills thousand upon thousands of workers each year with a combination of terrible regulation of mining practices, inherent danger and bronchus invading dust
Energy Source Breakdown (in %) Of Global Primary Energy Supply
As a point of interest, the following energy sources provided these %’s of the world’s primary energy supply in 2015:
Oil – 31.7%
Coal – 28.1%
Natural Gas – 21.6%
Hydro – 2.5%
Solar – less than 1%
Wind – less than 1%