Showing posts with label livestock. Show all posts
Showing posts with label livestock. Show all posts

June 17, 2010 - hay is for horses

Thursday, June 17, 2010

Yesterday, I looked at the U.S.'s historic energy usage.  In 1900, according to the U.S. Census, there were 76,094,000Americans, who consumed an estimated 9.587 quad of energy.  This works out to 125 million Btu per capita -- about 38% of today's U.S. per capita energy intensity.  As noted yesterday, I suspect this figure does not include the substantial energy that was used to feed draft livestock in 1900.  We don't usually think of livestock fodder as containing solar energy, but in a very real way, photosynthesis has been a major energy base for millennia.

To that end, I found an interesting note in the Thirty-Fifth Annual Report of the Secretary of the Maine Board of Agriculture, from 1892:

OUR HAY CROP.
By W. B. Kendall, Delivered at Clinton.

IMPORTANCE.

' On July 4th of each year our State of Maine celebrates its agricultural independence, by presenting its farmers with a constant, and never-failing million ton crop of grasses, the great basis of our agricultural life and wealth, in this northern clime.

So constantly do we gather this king of all crops into our barns, that, while almost every year, some of our cultivated crops, through drought, flood, insect blight or "season" are failures, the great hay crop, because ever present, is not given the gravity of consideration it demands. The hay crop of Maine has averaged, for the past ten years, one and one quarter million tons. At 87 per ton in the field $8,750,000 and at 810 per ton in the barn, $12,250,000,or more than the value of all others combined. We hear much of Maine's great lumber crop, and industry, but even this does not, in primal value, nor in the capital invested in its manufacture, nor in value after it is manufactured, amount to as much as the value of the hay crop in the field, the labor, machinery and barns for its storage and the cash value of the same delivered in Boston market, or consumed on the farm.

Our hay crop, the basis of our dairy industry, supports through our northern winters 1,100,000 head of cattle, horses and sheep.

In fact, a total failure of our hay crop for three years would practically depopulate our State, farm, town and city.

The agricultural report focuses on Maine's export of hay to southern New England, both to feed livestock used for food production (like the dairy farms) and to feed draft animals.  When you drive around the Maine countryside today, and see the hay fields that remain scattered here and there, it's easy to forget that all that hay is a vehicle for storing and consuming solar energy -- and that Maine has a long history of exporting that energy southward.

June 16, 2010 - a look into historic energy usage

Wednesday, June 16, 2010

The United States Energy Information Administration tells us that in 2008, Americans consumed 99.304 quadrillion Btu of "primary energy" resources.

How much is that? One quadrillion Btu, or "quad", is one thousand million million Btu, or 10^15 Btu. One quad is roughly the amount of energy contained in:
* 8,007,000,000 Gallons (US) of gasoline
* 293,071,000,000 Kilowatt-hours (kWh)
* 36,000,000 tons of coal
* 970,434,000,000 Cubic feet of natural gas
* 5,996,000,000 gallons of diesel oil
* 25,200,000 tons of oil

Dividing the 99.304 quads by the U.S. population, each American is responsible for 327 million Btu annually. Energy intensity, or the annual per capita consumption, peaked for America in 1978-1979 at 359 million Btu, but we've been moving back and forth above 311 million Btu since 1968.

How do these numbers compare to historic figures? US EIA has an interesting table showing estimated primary energy consumption for the U.S. for 1635-1945. The table shows 0.001 quad consumption in 1645, the first year for which data is provided. By 1835, the figure has broken above one quad (1.305 quad). Energy consumption grows fairly linearly through 1900 (9.587 quad), after which the figure shoots up sharply.

In 1835, the official U.S. population was 14.7 million. This gives an 1835 intensity of 88 million Btu -- about one quarter of today's per capita consumption.

Interestingly, I suspect these figures don't take into account the literal horsepower provided by livestock in 1835. How much more energy do we really consume today?