5 facts about energy sources

We've had a number of questions on energy sources in the United States–particularly with respect to the generation of electricity. Here are a few interesting facts about recent trends that hopefully help clarify some of the confusion surrounding this topic.

1. The amount of electricity generated in the US in 2013 is virtually the same as in 2005 (about 11.1 million megawatthours per day according to EIA). This is in spite of the economy and the population being significantly larger. Efficiency improvements have been impressive.

2. Coal remains the primary fuel for power generation, with natural gas not far behind.

Source: EIA

3. Renewable energy (outside of hydro) has had the largest growth rate, doubling since 2005. Evidence suggests that at least a portion of this increase has been due to tax incentives rather than market-based reasons. Hydro and nuclear have remained virtually unchanged over the past 7 years, while natural gas is gradually gaining on coal. Petroleum usage to generate power has declined the most due to its high cost as well as other issues. These trends are expected to continue.

Source: EIA

4. Within the renewable energy space the largest drivers of growth have been wind power and liquid biofuels (bioethanol and biodiesel). Growth in biofuels however has slowed in the last couple of years (in part due to higher corn prices).

Source: EIA

It is important to point out that unfortunately in spite of this growth and with all the tax incentives, renewables (outside of hydroelectric) remain a fraction – around 6% – of total electricity production in the US. By 2040 that number is expected to only increase to around 9% (16% including hydroelectric). It will be a couple of generations or more before renewable energy becomes a viable alternative to fossil fuels. Data suggests that for now, particularly on a global scale, the only energy source that can challenge hydrocarbons is nuclear.

5. And since we are on the topic of nuclear power as a real potential challenger to the more traditional fuel types, let's look at the safety issue. Isn't nuclear power dangerous? Here we have some data on safety by fuel type, showing the number of cases of death per one terawatt-hour of electricity by energy source. For example 4 people will die for every terawatt-hour of electricity generated via natural gas. One terawatt-hour is enough energy to power a 200,000 person city for a full year – making natural gas one of the safer fuels. Now compare that to coal and to nuclear.