Post Index

Suggested Reading Paths

Not all posts are the same quality or have the same impact.  If you are new to Do the Math, I recommend the following paths.  A chronological list appears at the bottom. But if starting fresh, one approach would be to read the 2021 textbook, Energy and Human Ambitions on a Finite Planet (the link is to the top-level permanent location; one more click to get to the first edition as a free PDF).  The textbook is a polished synthesis of the Do the Math arc plus some new thinking.

Growth and Sustainability

First, one of my most important messages is that we need to shake the religion of growth.  We simply can’t continue growing indefinitely.  Either we use our brains to plot a trajectory into steady-state and hope it’s smooth, or we let nature decide how to deal with us.  So start with the inaugural pair of posts: Galactic Scale Energy and Can Economic Growth Last? (perhaps also see the dinner conversation with an economist on this topic), then follow-up with Sustainable Means Bunkty to Me. In the same vein, you may want to check out Discovering Limits to Growth.  Perhaps one of my more important contributions is The Energy Trap, describing the dis-incentive we will face in trying to pull out of an energy decline with renewable infrastructure.

A common reaction to my statements of limited growth take to space as the answer.  I am less convinced that this is a viable path.

A major impetus for my interest in energy topics is peak oil.  My views on the subject are described in Peak Oil Perspective (and 2015 update).  Our attitudes toward the possibility of decline/collapse put us in greater jeopardy—we may need an attitude adjustment.  In fact, we’re so boxed in that we would do well to settle for a slower, simpler life. Yet we have a tendency to engage in ruthless extrapolation, assuming that our recent tear of progress will launch us into an ever-more-glorious future. When science tells us we can’t have all we want, we tend to dismiss it.

An audio recap of many of these themes can be found on the Chris Martenson podcast.

Alternative Energy

How do we get out of the fossil fuel box?  The first step is to establish the scale at which various sources might contribute.  By the numbers, solar is a can-do resource, and wind has large-scale capability as well. Tidal is cute in special locations, but cannot be a major player. Hydroelectric has been an important renewable resource, but its reach is very limited, and the low hanging fruit is plucked.  Nuclear fission is complicated, but certainly a strong possibility—fusion less so.  Additional posts cover biofuels, geothermal energy, solar thermal, energy from ocean thermal, currents, and waves, etc. Future posts will explore other options as well.  You may also be interested in the post assessing the scale of energy use, in visual form.

Then I have the alternative energy sources from the previous paragraph summarized into a scoring matrix that highlights the difficult path ahead, and the comparative inadequacy of our current suite of alternatives to that of fossil fuels.  Unconventional fossil fuels may help soften the liquid fuel decline, but this is also hard.

Easier Said than Done

Many posts are technical assessments of why our future is easier said than done.  For energy storage issues, we have Got Storage? How Hard Can It Be?A Nation-Sized Battery, and one on Pumped Storage.  Overblown claims of energy “solutions” can be found in Garbage In, Garbage Out.  A review of why photovoltaics (PV) will unlikely get much better than 15% (and why this is good enough) is in Don’t be a PV Efficiency Snob.  The hurdles involved in space-based solar power are also evaluated.  A look at biofuels is at The Biofuel Grind.


One thread in the posts deals with transportation.  The first examines the feasibility of achieving 100 MPG on gasoline.  Next is a look at how to assess energy requirements of electric cars (also a look at battery development), and compare to the MPG measure.  EVs have their set of intrinsic problems that may keep them from exploding onto the scene.  We then look at what it would take to have a solar-powered car, and also evaluate personal transportation efficiency.  Finally, we turn the question to ourselves as humans as walkers and cyclers: what is the MPG for a Human?

Home Energy, Explored

Treating energy as precious across the board, we can make gigantic changes to the amount we use without dropping out of society.  Tracing my own path, we first look at pilot lights, and the dramatic impact this led to in home heating practices (now using a fifth of the gas I used to).  Likewise, I have trimmed my utility electricity use by a factor of five—thanks in part to an off-grid solar installation (efficiency report here, also untimely death of battery), and due to almost no use of air conditioning.  I have cut back on use of gasoline as well.  Dietary choices can also have a big impact on personal energy: especially meat vs. veggie choices.

I recap the various avenues of personal energy savings and compare this to the national average, musing also about ways to make this a more widely practiced endeavor.

In my quest to measure and understand energy use, I have detailed the maximum efficiency achievable by lighting, and have measured the efficiency of heating/boiling water by a variety of methods.  I am also a compulsive collector of data, and offer glimpses of electrical activities/devices in my home.  Most recently, I used a blower door to explore where the draft demons dwell.

Climate Change

I am frankly surprised that posts on climate change receive a collective “Meh.”  In truth, I’m with you.  But if climate change is your thing, read about how straightforward it is in A Recipe for Climate Change.  For carbon capture and storage, look at Putting the Genie Back in the Toothpaste Tube.

Chronological Post Listing

  1. Galactic Scale Energy—absurdity of continued physical growth
  2. Can Economic Growth Last?—impossibility of indefinite economic growth
  3. 100 MPG on Gasoline: Could We Really?—physical limits to arbitrary fuel economy
  4. A Nation-Sized Battery—lead acid can’t scale to solely supply our nation
  5. Does the Logistic Shoe Fit?—falling away from exponential energy growth
  6. Personal Energy Cubes—visualizing your energy footprint; solar comparison
  7. A Recipe for Climate Change—it’s obvious climate change is anthropogenic
  8. MPG for Electric Cars?—proper measure is kWh/100 km (or the like)
  9. Garbage In, Garbage Out—energy from waste streams is small beans
  10. Discovering Limits to Growth—distillation of landmark 1972 work
  11. Power Out, People Out—the San Diego blackout, and lessons learned
  12. Got Storage? How Hard Can It Be?—home storage is not easy without FF
  13. Don’t be a PV Efficiency Snob—15% is just fine for what we need to do
  14. Putting the Genie Back in the Toothpaste Tube—carbon capture & storage
  15. Sustainable Means Bunkty to Me—the daunting scale of the steady state
  16. Why Not Space?—space does not solve our finite world problems
  17. The Energy Trap—up-front energy investment cripples new energy infrastructure
  18. Stranded Resources—inaccessibility of space resources for energy or materials
  19. Peak Oil Perspective—why I think peak oil is a serious issue
  20. Growth Has an Expiration Date—a pointer to a talk covering posts 1, 2, 15, and 17
  21. The Biofuel Grind—the hard work and difficult-to-scale nature of biofuel options
  22. Pump Up the Storage—explores the scale of pumped storage for a national battery
  23. A Solar-Powered Car—looks at the practicalities of solar-powered personal transport
  24. MPG for a Human—how efficient are humans at moving ourselves about?
  25. Wind Fights Solar; Triangle Wins—evaluates potential scale in both solar and wind
  26. Can Tides Turn the Tide?—the potential scale of tidal power (wimpy)
  27. How Much Dam Energy Can We Get?—how much hydroelectric potential awaits?
  28. The Future Needs an Attitude Adjustment—tantrums don’t help: more adults needed
  29. Nuclear Options—an intro to nuclear fission and some pros and cons
  30. Warm and Fuzzy on Geothermal?—how much power/energy is in the hot Earth?
  31. Basking in the Sun—getting heat from our sun for home, water, and electricity
  32. The Motion of the Ocean—energy from ocean thermal gradients, currents, waves
  33. Nuclear Fusion—what it is, why it’s so hard, and why it’s unlikely to save us
  34. Alternative Energy Matrix—a summary table of all this hard work
  35. Fossil Fuels: I’m Not Dead Yet—can unconventional FF replace waning liquids?
  36. The Way is Shut—we’re in a box, and the best option may be to go backwards
  37. My Great Hope for the Future—dare we think about slowing down, using less?
  38. Pilot Lights are Evil—70% of my warm-season gas use was in pilot lights!
  39. Home Heating for the Hardy—gigantic energy savings possible, totally tolerable
  40. Space-Based Solar Power—why make solar vastly harder for little gain?
  41. The Phantoms I’ve Killed—factor-of-five reduction of electricity usage
  42. Heat Those Feet!—an energy comparison of foot-heating strategies
  43. Exponential Economist Meets Finite Physicist—a dinner conversation
  44. Easing Off the Gas—schemes to reduce personal use of liquid fuels
  45. Flex-Fuel Humans—diet choices can have a big impact on energy use
  46. My Neighbors Use Too Much Energy—recap of savings, and how to export
  47. Supermoon Disappointment—not about energy, but doing the math on astro-hype
  48. Spectral Extravaganza: The Ultimate Light—how efficient can lighting possibly be?
  49. Chris Martenson podcast—a recap of my thoughts in audio format
  50. Burning Desire for Efficiency—how much energy does it really take to heat water?
  51. Heat Pumps Work Miracles—how we get better than 100% efficiency from pumps
  52. Ruthless Extrapolation—we’re accomplished at assuming recent trends continue
  53. TED-Stravaganza—what we learn about the secret electrical lives of our devices
  54. My Modest Solar Setup—a small stand-alone, off-grid installation I whipped up
  55. Solar Data Treasure Trove—the 30-year NREL database rendered graphically
  56. Battery Performance Deficit Disorder—battery research stalled, short of goals?
  57. Rocking the AC—an air conditioning experiment exposes alarming consumption
  58. Blow-by-Blow PV System Efficiency—how my off-grid solar setup performs
  59. The Energy-Water Nexus—water needs energy and energy needs water
  60. When Science is a Conveyor of Bad News—do we kill the messenger?
  61. Futuristic Physicists?—Do physicists think we’ll get our sci-fi future?
  62. Crippling Intellects—Sometimes people are so smart as to be dumb
  63. This Thermal House—Explores thermal properties of houses, insulation
  64. Death of a Battery—Lead-acid batteries stink, except they’re the best option
  65. Let’s Blow this Joint—Using a blower door to ferret out drafts
  66. Elusive Entropy—not the disorder your grandfather went on about
  67. Man Bites EV—EVs still have fundamental problems, despite my buy-in
  68. The Real Population Problem—does surplus energy grow babies (somewhere)?
  69. The Already-Written Future?—short comment on nonsense population article in NYT
  70. A Physics-based Diet—mass in equals mass out: eat less, breathe more
  71. Putting PV to Pasture?—is solar’s goose cooked?
  72. Tuning in in Noise—a rant about Poisson statistics in low-score sports
  73. Peak What?—is peak oil even a thing?
  74. BBC Questions Indefinite Growth—an interview about growth perspectives
  75. Programmed to Ignore—personality types bake in resistance to message
  76. My Chicken of an EV—helplessly watching my PHEV battery decline
  77. You Call this Progress?—examining myths about breakneck speed of change
  78. Textbook Debut—I wrote a book! I’m excited; are you?
  79. Textbook Tour—what’s new for Do the Math readers?
  80. Sir David Nails It—Attenborough digs deep and lands some killer quotes
  81. Earth’s Real Treasure—comparing the value of animals to that of gold
  82. Ultimate Success—a 10,000 year view of what success must mean

Hits: 2255