Heat those Feet!

Posted on 2012-04-03 by tmurphy

Infrared image of a cold left foot (25°C with 19°C toes), compared to a warm (33°C) right foot.

One of the more bothersome aspects of living in an unheated house (with tile floors in much of the house, in my case) is having cold feet. Spring has arrived, so perhaps this post is not as timely as it might otherwise have been. But let’s consider the energy costs of various approaches to warming up cold feet.

The main problem I have with cold feet is that they make it hard to go to sleep. Otherwise cold feet don’t seem to distract me from normal activities. But let’s say that your feet are cold and that you cannot stand it any longer, and therefore must warm them up. I’ll look at a number of options, assessing how much energy is consumed for each. We’ll try hot water in the sink, a space heater (or blow dryer) under a blanket, a heating pad wrapped around the feet, or good-old metabolic energy.

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The Phantoms I’ve Killed

Posted on 2012-03-27 by tmurphy

Two weeks ago, I described my factor-of-five reduction of natural gas usage at home, mostly stemming from a decision not to heat our San Diego house. We have made similar cuts to our use of utility electricity, using one-tenth the amount that comparable San Diego homes typically consume. In this post, I will reveal how we pulled this off…with plots. Some changes are simple; some require behavioral changes; some might be viewed as outright trickery.

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OilPrice Interview

Posted on 2012-03-21 by tmurphy

If you’re interested, oilprice.com posted an interview polling my take on energy alternatives and related issues. Regular Do the Math readers have likely heard much of it before, but perhaps will enjoy a different packaging…

Space-Based Solar Power

Posted on 2012-03-20 by tmurphy

A solar panel reaps only a small portion of its potential due to night, weather, and seasons, simultaneously introducing intermittency so that massive storage is required to make solar power work at a large scale. A perennial proposition for surmounting these impediments is that we launch solar collectors into space—where the sun always shines, clouds are impossible, and the tilt of the Earth’s axis is irrelevant. On Earth, a flat panel inclined toward the south averages about 5 full-sun-equivalent hours per day for typical locations, which is about a factor of five worse than what could be expected in space. More importantly, the constancy of solar flux in space reduces the need for storage—especially over seasonal timescales. I love solar power. And I am connected to the space enterprise. Surely putting the two together really floats my boat, no? No.

I’ll take a break from writing about behavioral adaptations and get back to Do the Math roots with an evaluation of solar power from space and the giant hurdles such a scheme would face. On balance, I don’t expect to see this technology escape the realm of fantasy and find a place in our world. The expense and difficulty are incommensurate with the gains.

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Home Heating for the Hardy

Posted on 2012-03-13 by tmurphy

Sleeping warm

If you are on-board with the sentiment that we should strive to reduce the amount of energy we consume as a means to relieve pressure on a world suffering impending energy scarcity, then you probably want to know how one might proceed. In this post, I will describe the single-biggest energy-saving strategy I have employed in my home in the past five years, which slashed my natural gas consumption by almost a factor of five.

Last week, I described how to read gas meters, in the process discovering how onerous pilots lights can be. As a result of initial exploration of my energy footprint in the spring of 2007, I shut off the furnace pilot light for the summer, which I figured accounted for two-thirds of my warm-season natural gas use. When winter came, my wife and I challenged ourselves to hold off on re-igniting the pilot light until it got too cold for us to bear. That day never came. The result was a dramatic reduction in natural gas use.

In this post, I will talk about some of the ups and downs of adjusting to a colder house in the winter. Granted, we live in moderate San Diego, and could not get away with the same tactic in many locales. Even so, I will quantify the gains one might expect elsewhere for similar living conditions.

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Pilot Lights are Evil

Posted on 2012-03-06 by tmurphy

familyhandyman.com

My personal journey into home energy reduction began with taking stock of past energy use as reported on my utility bills. I quickly migrated toward reading the meters directly to gauge the impact of particular activities. What I learned from our gas meter shocked me, and ultimately led to our single-biggest energy-saving behavioral shift. I’ve already ruined any hope of suspense in the title of the post, but just how bad does something have to be before I’ll resort to a word like “evil?” And how bad are your own demons? Ah—now you can’t wait to find out!

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My Great Hope for the Future

Posted on 2012-02-28 by tmurphy

So far on Do the Math, I’ve put out a lot of negative energy—whatever that means. Topics have often focused on what we can’t do, or at least on the failings or difficulties of various ambitious plans. We can’t expect indefinite growth—whether in energy, population, or even growth of the economic variety. It is not obvious how we maintain our current standard of living once fossil fuels begin their inexorable decline this century. And as I’ve argued before, achieving a steady-state future implies approximate equity among the peoples of the Earth, so that maintaining today’s global energy consumption translates to living at one-fifth the power currently enjoyed in the U.S.

In this post, I offer a rosy vision for what I think we could accomplish in the near term to maximize our chances of coming out shiny and happy on the tail end of the fossil fuel saga. I’m no visionary, and this exercise represents a stretch for a physicist. But at least I can sketch a low-risk, physically viable route to the future. I can—in part—vouch for its physical viability based on my own dramatic reductions in energy footprint. I cannot vouch for the realism of the overall scheme. It’s a dream and a hope—a fool’s hope, really—and very, very far from a prediction or a blueprint. I’ve closed all the exits to get your attention. Now we’ll start looking at ways to nose out of our box in a safe and satisfying way.

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The Way is Shut

Posted on 2012-02-21 by tmurphy

When I first approached the topic of societal energy in 2004, I became aware for the first time that our energy future was not in the bag, and proceeded to explore alternative after alternative to judge the viability and potential pitfalls of various options. I have retraced my steps in Do the Math posts, exposing the scales at which different energy sources might contribute, and the practical complexities involved. My spooky campfire version of the story, a la Tolkien: The Way is Shut.

Alright, I’m overstating things a bit. The good news is that there do exist energy flows and sources that qualify as abundant or at least potent. However, many of the alternatives represent ways to produce electricity, which applies only to about one-third of our current energy demand. The immediate threat is therefore the short term liquid fuels crunch we will see when the global petroleum decline commences within the decade.

In this post, I will reflect on the lessons we learn after having characterized the various alternatives to fossil fuels. There will still be some tidying-up to do on energy alternatives not treated thus far, but by and large the nature of content on Do the Math is about to pivot toward addressing the question “What can we do now?” In some sense, a common thread so far has been: “easier said than done,” or “don’t count on that technology saving our bacon.” I’ve closed all the exits to get your attention. We’re boxed in. Okay, the exits aren’t really closed: they’re just not as wide open as they would need to be for me to be complacent. So now we’ll start looking at ways to nose out of our box in a safe and satisfying way.

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Fossil Fuels: I’m Not Dead Yet

Posted on 2012-02-14 by tmurphy

From Monty Python: “Bring out your dead”

Having looked at the major alternatives to fossil fuel energy production (summarized here), we come away with the general sentiment that the easy days of cheap energy are not evidently carried forward into a future without fossil fuels. That’s right, fossil fuels will be dead and gone. Is it time to pile them on the cart to be hauled away?

In the slapdash scoring scheme I employed in the alternative energy matrix, the best performers racked up 5 points, whereas by the same criteria, our traditional fossil fuels typically achieved the near-perfect score of 8/10. The only consistent failing is in the abundance measure, which is ultimately what brings us all together here at Do the Math. Fossil fuels are presently used in abundance—85% of current energy use—but this is a short-term prospect, ending within the century. The first effects of decline may be close at hand. Do I hear talk of nursing homes?

The gulf between fossil fuels and their alternatives tends to be rather large in terms of utility, energy density, practicality, ease of use, versatility, energy return on energy invested, etc. In other words, we do not merrily step off the fossil fuel ride onto the next one by “just” allowing the transition to happen. The alternatives come at a cost, and we will miss the golden days of fossil fuels. But wait…what’s that murmur? Not dead yet?

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The Alternative Energy Matrix

Posted on 2012-02-07 by tmurphy

[An updated treatment of this material appears in Chapter 17 of the Energy and Human Ambitions on a Finite Planet (free) textbook.]

Breathe, Neo. I’ve been running a marathon lately to cover all the major players that may provide viable alternatives to fossil fuels this century. Even though I have not exhausted all possibilities, or covered each topic exhaustively, I am exhausted. So in this post, I will provide a recap of all the schemes discussed thus far, in matrix form. Then Do the Math will shift its focus to more of the “what next” part of the message.

The primary “mission” of late has been to sort possible future energy resources into boxes labeled “abundant,” “potent” (able to support something like a quarter of our present demand if fully developed), and “niche,” which is a polite way to say puny. In the process, I have clarified in my mind that a significant contributor to my concerns about future energy scarcity is not the simple quantitative scorecard. After all, if it were that easy, we’d be rocking along with a collective consensus about our path forward. Some comments have asked: “If we forget about trying to meet our total demand with one source, could we meet our demand if we add them all up?” Absolutely. In fact, the abundant sources technically need no other complement. So on the abundance score alone, we’re done at solar, for instance. But it’s not that simple, unfortunately. While the quantitative abundance of a resource is key, many other practical concerns enter the fray when trying to anticipate long-term prospects and challenges—usually making up the bulk of the words in prior posts.

For example, it does not much matter that Titan has enormous pools of methane unprotected by any army (that we know of!). The gigantic scale of this resource makes our Earthly fossil fuel allocation a mere speck. But so what? Practical considerations mean we will never grab this energy store. Likewise, some of our terrestrial sources of energy are super-abundant, but just a pain in the butt to access or put to practical use.

In this post, we will summarize the ins and outs of the various prospects. Interpretation will come later. For now, let’s just wrap it all up together.

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