In the summer of 2001, The National Environmental Education Foundation conducted a survey of 1,503 American adults about energy. Although 75% of those surveyed said they knew “A Fair Amount” or “A Lot” about energy, only 12% could correctly answer 7 or more questions on a 10 question energy quiz. The quiz is on pages 4 and 5 of the report (pages 15 and 16 of the PDF). So what’s your “energy IQ”?
In earlier years of Lawrence Livermore National Laboratory’s spaghetti diagrams, such as the above example from 1976, the ends of the swaths were more like the simpler energy flow diagrams. On the above diagram it’s easier to see that the height of the lines on one side would end up around the height of the lines on the other side than it is on some of the newer versions with oversized boxes that serve as labels. But the boxes are a useful tool, and can let us think about embedding another diagram form — box diagrams — into the spaghetti diagram.
Box diagrams are used for teaching electricity, and were developed by Peter Cheng and David Shipstone in the UK. The picture below is from part 1 (Word doc) of their introductory paper (here’s the Word doc part 2). Since power is the voltage across a bulb multiplied by […]
This “spaghetti diagram” (aka Sankey diagram, or Energy Flow Chart officially) is the 2008 version. Lawrence Livermore National Lab (LLNL) has been making these things since the 1970s. It’s more detailed than a simpler national energy flow diagram because it includes “rejected energy.” It’s also more complex — it actually includes within itself the electricity flow diagram. It’s a pretty cool visualization.
The main thing I dislike is that it doesn’t split up transportation or electricity generation “rejected energy” by sector. Since these are really the two biggest sources of “rejected energy,” you can’t see which group is the biggest “rejector.”
Below, in an undated but funkier design, they’ve not only split up transportation into light duty vehicles, freight/other, and aircraft, they’ve also added domestic and net imports to petroleum and natural gas. They still haven’t split up “Electricity Generation, Transmission & Distribution Losses,” so we don’t know who […]
Here’s a picture from What You Need to Know about Energy by the National Academy of Sciences. It shows 100 energy units of coal being used by an incandescent bulb to produce light that has only 2 energy units:
Reprinted with permission from "What you need to know about energy," 2008, by the National Academy of Sciences, Courtesy of the National Academies Press, Washington, D.C.
Incandescent bulbs get hot because only 2/36 (about 5%) of the energy coming into the house to power the bulb comes out as light — the rest of the energy produces heat. If you trace the energy back to the power plant, it turns out a mere 2% of the energy from the coal is doing the desired lighting job! The power plant itself loses 62% of the coal’s energy! Compact fluorescents use about 5% of the coal’s energy — better, but not […]
Energy is measured in Joules (J) Power is measured in Watts (W). 1 Watt = 1 Joule / second
If you would like to quantitatively understand the relationship between your lifestyle, global energy use, and climate change, you need to establish the language with which you can translate between these things. There are many different ways we use energy, many different ways we produce energy, and many different consequences environmentally. Power and energy are being measured around us all of the time. You get your electricity bill in kilowatt hours (kWh), your gas bill in Therms or British Thermal Units (BTUs), your car’s performance is measured in horsepower, and your lightbulbs are rated in watts. To compare these things you need a common set of units. The first problem with comparing these things is that some of them (BTUs and kWh) are measures of energy consumed, and some of them […]
If you would like to quantitatively understand the relationship between your lifestyle, global energy use, and climate change, you need to establish the language with which you can translate between these things. There are many different ways we use energy, many different ways we produce energy, and many different consequences environmentally. Power and energy are being measured around us all of the time. You get your electricity bill in kilowatt hours (kWh), your gas bill in Therms or British Thermal Units (BTUs), your car’s performance is measured in horsepower, and your lightbulbs are rated in watts. To compare these things you need a common set of units. The first problem with comparing these things is that some of them (BTUs and kWh) are measures of energy consumed, and some of them (horsepower and watts) are measures of power. To understand the rest of this book, you need an intuition for […]
Today I’m doing a webcast for O’Reilly media on Energy and Energy Literacy. I’m making the slides available here:
I’m continually reminded of how difficult it is for people just go get past the difference between energy and power. To get a full picture of rate of energy use (power) we need to talk about both and their units, but it certainly makes it a cumbersome conversation to join afresh.
Here’s a document from 1982, A Conceptual Framework for Energy Education, K-12, commissioned by the Department of Energy. On page 7 is a description of an “energy-literate citizen”:
Understands that we can’t make energy. Finds more efficient ways to use energy at home, at school, and on the job, for example through the use of waste heat. Has some historical perspective on energy use and extraction; for example, has an informed notion of where we stand on the fossil fuel depletion curve. Compares life-cycle costs in deciding on major purchases. Invests to save energy, for example by purchasing home insulation when it is cost-effective. Knows how much energy is being used in his/her household and where it goes. Is aware of the major sources of the energy used in his or her immediate job and in the economy as a whole, including their relative size. Understands that all energy use […]
It contains the good the bad and the ugly of climate and energy books. Over time it will become more comprehensive and you’ll see loads of reviews coming up on the blog as I do an editorial on each of the books. For now just broswe the shelves:
And if you are a mac user, definitely try using delicious library as a management tool for your books. It’s fantastic.
Disclaimer: the books in the library are under an amazon affiliates program that puts money towards: www.howtoons.com