Joules, BTUs, Quads—Let’s Call the Whole Thing Off
Illustration: Bryan Christie Design

The fact that energy sources and uses are stated in so many different kinds of terms is increasingly seen as not merely an annoyance but as a serious impediment to public understanding of critical choices. In an effort to get matters onto a more intuitive, citizen-friendly basis, a number of experts have hit on the convenient fact that the world at present consumes about 1 cubic mile of oil (CMO) per year. Among these experts are Ed Kinderman and Hewitt Crane at SRI International, in Menlo Park, Calif., who are preparing a book for Oxford University Press that will be built around the idea of normalizing all energy units to 1 CMO (4.17 cubic kilometers).

One dramatic way of portraying their results is to ask how many alternative energy sources—say coal-fired plants or solar panels—it would take to produce the equivalent of one CMO.

Amplifying on the rationale for CMO, Ripudaman Malhotra—an SRI chemist and a colleague of Kinderman and Crane—puts it like this: “When talking about energy and its different sources, we run into two main problems that impede meaningful discussion. If you ask the question—How much energy does the world use in a ­second?—you get answers that combine many different units: 150 tons of coal, 37 000 gallons of oil, 3.2 million cubic feet of gas, and so on.”

“The second problem,” Malhotra says, “is that these units themselves represent fairly small amounts of energy, and one needs modifiers such as millions, billions, and trillions in front of them. It is difficult to keep these numbers straight, and there are examples in the press when million was used when the intent was to use a billion.”

“Remember also that billion means 1012 in the UK and not 109 as per the U.S. usage,” Malhotra adds.

Some results of the exercise are displayed here. Prepare for your mind to be wonderfully sobered. To obtain in one year the amount of energy contained in one cubic mile of oil, each year for 50 years we would need to have produced the numbers of dams, nuclear power plants, coal plants, windmills, or solar panels shown here.

The Three Gorges Dam infographic Assumptions: The Three Gorges Dam is rated at its full design capacity of 18 gigawatts. A nuclear power plant is postulated to be the equivalent of a 1.1-GW unit at the Diablo Canyon plant in California. A coal plant is one rated at 500 megawatts. A wind turbine is one with a 100-meter blade span, and rated at 1.65 MW. A solar panel is a 2.1-kilowatt system made for home roofs. In comparing ­categories, bear in mind that the average amount of time that power is produced varies among them, so that total energy obtained is not a simple function of power rating. Illustration: Bryan Christie Design

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Smart image analysis algorithms, fed by cameras carried by drones and ground vehicles, can help power companies prevent forest fires

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The 2021 Dixie Fire in northern California is suspected of being caused by Pacific Gas & Electric's equipment. The fire is the second-largest in California history.

Robyn Beck/AFP/Getty Images

The 2020 fire season in the United States was the worst in at least 70 years, with some 4 million hectares burned on the west coast alone. These West Coast fires killed at least 37 people, destroyed hundreds of structures, caused nearly US $20 billion in damage, and filled the air with smoke that threatened the health of millions of people. And this was on top of a 2018 fire season that burned more than 700,000 hectares of land in California, and a 2019-to-2020 wildfire season in Australia that torched nearly 18 million hectares.

While some of these fires started from human carelessness—or arson—far too many were sparked and spread by the electrical power infrastructure and power lines. The California Department of Forestry and Fire Protection (Cal Fire) calculates that nearly 100,000 burned hectares of those 2018 California fires were the fault of the electric power infrastructure, including the devastating Camp Fire, which wiped out most of the town of Paradise. And in July of this year, Pacific Gas & Electric indicated that blown fuses on one of its utility poles may have sparked the Dixie Fire, which burned nearly 400,000 hectares.

Until these recent disasters, most people, even those living in vulnerable areas, didn't give much thought to the fire risk from the electrical infrastructure. Power companies trim trees and inspect lines on a regular—if not particularly frequent—basis.

However, the frequency of these inspections has changed little over the years, even though climate change is causing drier and hotter weather conditions that lead up to more intense wildfires. In addition, many key electrical components are beyond their shelf lives, including insulators, transformers, arrestors, and splices that are more than 40 years old. Many transmission towers, most built for a 40-year lifespan, are entering their final decade.

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