Part the First: Brief Background on Emissions Factors
Electricity generation accounts for almost one-third of US territorial greenhouse gas emissions, and the average US residence consumes just under 11,000 kilowatt-hours (kWh) electricity per year (in addition to other fuels, such as natural gas). Thus, it is essential to understand the impact of electricity use, and especially how changes in use at the household level will affect emissions.
Everything that needs to be said has already been said. But since no one was listening, everything must be said again.
I too am reduced to repeating what must be said, and given this nascent blog’s readership, it seems rather likely that it will need saying again. To wit, George Monbiot recently discussed, in a melancholy but extremely important article (see also the version in The Guardian), the vanishing of so much nature and wild life before his own eyes, in his own lifetime. It is not mere false nostalgia, and he cites much published work that documents the astonishingly rapid and ongoing global loss of animal life, a process that has been variously (and by respectable scientists, no less!) termed “defaunation” in the “Anthropocene” and, more recently, a “biological annihilation.”
I wrote several hundred pages of a book that amounted to exhorting people to alter their own habits of residential energy consumption (turn down the heat, you rogues!), as well as upgrade their built environment (e.g. insulate the attic) and appliances, or even, *gasp*, add solar to their roofs. All this because the numbers, at least in the abstract, showed that such banal acts of conservation (not counting solar) can reduce the carbon footprint of residential energy use by at least 30-50%, from a baseline average of about 12 metric tonnes (1 tonne = 1 metric ton) of CO$_2$-equivalent (CO$_2$e). But a demonstration of how, over the course of roughly 5 years, the net energy use in my house actually fell progressively from around 17,000 kWh of electricity per year down to less than zero (net) seems in order.
I should like to highlight here (see also TomDispath.com version) a remarkable essay by Greg Grandin, one that contrasts two of Melville’s characters as faces of Empire: Captain Ahab and the historical sealing captain Amasa Delano, who partook in the massive late eighteenth century extirpation of seal populations in the South Pacific for fur, which was used a luxury item for the wealthy, and who put down a slave rebellion aboard a Spanish slave ship. Delano viewed himself as a moral man, one “who has a knowledge of his duty, and is disposed faithfully to obey its dictates.”
Unfortunately, as reported by the EIA, electrified drivetrains—hybrid-electric vehicles (HEVs), plug-in hybrid-electric vehicles (PHEVs), and battery electric vehicles (BEVs)—still make up only about 3% of new vehicle market share, a share that has been stable for the last five years, with HEVs continuing to account for most electrified drivetrain sales:
Although fuel economy has increased somewhat for conventional vehicles in the last few years, compared to typical gasoline vehicles, lifecycle greenhouse gas emissions are generally 30-60% lower for most alternative drivetrain vehicles (with some larger luxury vehicles exceptions to this rule).
Stay tuned for a more in-depth comparison of the top-selling HEVs, PHEVs, and BEVs…
A new analysis drawing on 570 studies with data covering 38,700 commercial farms shows dramatic variation both worldwide and within-region in the environmental impact across all major foods, but confirms that beef in particular and animal products in general are responsible for the greater part of food’s impact on earth, which adds up to 31% of global warming emissions (including non-food agriculture), and 43% of ice- and desert-free land. Supplementary material available for free (and is very comprehensive), while the main article is for subscribers only (here).
Poore, J., & Nemecek, T. (2018). Reducing food’s environmental impacts through producers and consumers. Science, 360(6392), 987-992.
Welcome to EnvironMath! Hopefully this will become a useful record of (sometimes) mathematically oriented reviews of topics in the environment (and perhaps other areas). To get started (and to shamelessly self-promote), I’m adding multiple (free) excerpts from my new book, A Fair Share: Doing the Math on Individual Consumption and Global Warming.