1. Definition and Energy Equivalents

The CMO is defined as the energy released by burning a cubic mile of oil. One cubic mile is equal to about 4.2 billion cubic metres, 4.2 cubic kilometres or 26 billion barrels. Since the energy released by burning oil is about 38 gigajoules per cubic metre (5.8 million British thermal units per barrel), ^[1], the energy released by burning one cubic mile of oil is approximately equal to:

• 1.6×10²⁰ joules or 160 exajoules
• 4.4×10¹³ kilowatt-hours or 44 petawatt-hours
• 1.5×10¹⁷ British thermal units or 150 quads

As the energy released by burning natural gas is about 38 megajoules per cubic metre (1,000 British thermal units per cubic foot), the same energy is released by burning 4.2 trillion cubic metres (150×10^¹² cu ft) of natural gas.

2. Annual Energy Consumption by Source

2008 worldwide renewable-energy sources. Source: REN21^[2] https://handwiki.org/wiki/index.php?curid=1659114

The world consumes approximately 3 CMO annually from all sources. The table ^[3] shows the small contribution from alternative energies in 2006.

A CMO/yr is about 5.084 TW continuous, making current world energy use around 15 TW.

3. Global Energy Reserves

Proved oil reserves are those that can be extracted with reasonable certainty under existing conditions using existing technology. Global proved oil reserves are estimated at approximately 1,300 billion barrels (210 billion cubic metres).^[4] This corresponds to roughly 43 cubic miles, or 43 CMO. At the current rate of use, this would last about 40 years. Technological advances, new discoveries, and political changes will likely lead to additional proved oil reserves in the future. Concurrently, the International Energy Agency predicted in its 2005 World Energy Outlook that the annual consumption will increase by 50% by 2030.^[5] Coal and natural gas currently provide 1.42 CMO of energy per year. Global reserves of these fossil resources are as follows:

• Natural gas reserves total 42 CMOs (69 years at current consumption)
• Coal reserves total 121 CMOs (150 years at current consumption)
• Additionally, there are large, albeit uncertain, amounts of tar sands, shale gas, and other unconventional fossil sources

4. Replacement of Oil by Alternative Sources

While oil has many other important uses (lubrication, plastics, roadways, roofing) this section considers only its use as an energy source.

The CMO is a powerful means of understanding the difficulty of replacing oil energy by other sources. In 2007, SRI International chemist Ripudaman Malhotra, working with Crane and colleague Ed Kinderman, used it to describe the looming energy crisis in sobering terms.^[6] Malhotra illustrates the problem of producing one CMO energy that we currently derive from oil each year from five different alternative sources. Installing capacity to produce 1 CMO per year requires long and significant development.

Allowing fifty years to develop the requisite capacity, 1 CMO of energy per year could be produced by any one of these developments:

• 4 Three Gorges Dams,^[7] developed each year for 50 years, or
• 52 nuclear power plants,^[8] developed each year for 50 years, or
• 104 coal-fired power plants,^[9] developed each year for 50 years, or
• 32,850 wind turbines,^[10][11] developed each year for 50 years, or
• 91,250,000 rooftop solar photovoltaic panels^[12] developed each year for 50 years

The energy produced is the power rating of the source multiplied by the duration it is operational. These comparisons take into account the variability of available power (solar panels work only during the day, turbines work only when the wind blows). In practice, due to losses as waste heat, it takes about 3 kWh (10,000 BTU) of primary heat energy to produce 1 kWh of electricity from coal and other fossil sources. Thus, when considering sources such as wind and solar which directly produce electricity, the required installed capacity was calculated by using 1 kWh as equivalent to 3 kWh (10,000 BTU).

The environmental, social, and financial costs of such development projects are immense:

• The Three Gorges Dam is the world's largest, flooding 632 km², displacing 1.25 million people, and costing roughly US$30 billion.
• A conventional nuclear power plant produces hazardous radioactive waste, raises fears of radiation or nuclear proliferation, requires 4 years to construct for a 60-year lifetime, occupies about 4 km², and may cost upwards of US$5 billion.
• A 500 MW coal-fired power plant may contribute to acid rain, global warming, and air pollution, occupies about 2 km², may obtain its fuel via controversial methods such as mountaintop removal, and costs about US$650 million.
• A large wind turbine requires a location with an abundance of steady wind, may be visually obtrusive, can interfere with aviation, needs about 0.16 km² to avoid interfering with adjacent turbines, and costs about US$2 million.^[13]
• A 2.1 kW rooftop solar array requires technical skills for installation, needs a sunny location, presents few aesthetic or environmental problems, covers about 14 m², but costs around US$15,000.

For comparison, US$3.2 trillion is the approximate gross domestic product of Germany, China, or the United Kingdom. The total land area of New Zealand is approximately 270,000 square kilometres (100,000 sq mi).^[14]

At a 2008 market price of US$120 per barrel (US$750/m³), the cost of one CMO was about US$3 trillion. So for the cost of about one year's global oil consumption at 2008 market prices, enough wind turbines could be built to generate the same energy for 40 years, assuming sites are available.

5. Replacement of Oil by Speculative Alternative Sources

Space-based solar power and solar power above the clouds offers potential future energy technologies. As about five terawatt equals one CMO per year, it would take about 1000 five gigawatt power satellites to replace a CMO. To compete with coal, the maximum cost for space-based solar power plants would be US$2.4 billion per gigawatt. At that, the cost would be about $12 trillion for one CMO or about $36 trillion to replace the entire fossil fuel use of humans, or about 45 % of the gross world product for one year ((As of 2017) about US$80 trillion^[15]). There is room in geostationary orbit for more than ten times the 2015 energy use.^[16] At a peak production of 315 new power satellites per year, it would take less than a decade to get off fossil fuels.

The potential future technology of solar power above the clouds has the advantage that solar can be tapped at 20 km regardless of the local weather.

In both cases, a huge energy flow to carbon-neutral synthetic fuel plants could be utilized for transport sectors where electrification pose a challenge, (As of 2020) for example aviation.