Energy consumption from 2008 to 2009 declined slightly, as did our efficiency:
http://www.dailykos.com/story/…
The estimated U.S. energy use in 2008 equaled 99.2 quadrillion BTUs (“quads”), down from 101.5 quadrillion BTUs in 2007…. Of the 99.2 quads consumed, only 42.15 ended up as energy services.
That’s a gross efficiency of 42.49%. We waste more energy than we use.
Electricity production operates at 31.63% and transportation at 24.98% efficiency. Tell me again why energy efficiency isn’t the top priority in our energy debate.
http://www.dailykos.com/story/…
According to [Thomas] Casten [of Recycled Energy], energy waste is pervasive and endemic throughout our electrical system but invisible in our policy discussions. The average US power plant operates at 33% efficiency and throws away 66% of the energy it produces through waste heat, transmission and distribution losses, and other inefficiencies. There are even greater losses before you get to the end use of that electricity. For instance, an incandescent light has an end use efficiency of about 3% [somebody should tell Rand Paul]. Furthermore, the level of electricity efficiency stagnated in 1960. For the last 50 years, there has been no growth in average efficiency in our power plants and the conversion of energy to useful work (exergy, exergy, exergy) actually began declining in 2000.
There is some good news in this chart in that the residential, commercial, and industrial uses of energy operate at about 80%.
Plus, if we look back to Amory Lovins’ 1976 Foreign Affairs article “The Road Not Taken,” we will see that the projections then were for the US to use about twice the energy that we do now. We have grown our economy enormously (believe it or not) since 1976 but we haven’t been as wasteful of energy as we thought we would be.
These are just gross numbers, a first cut at basic analysis, but what they reveal may be useful.
and have been enjoying this chart for about five years.
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p>On waste:
1. The second law of thermodynamics ensures that we can’t be 100% efficient. In fact, it’s awfully hard to be even close.
2. In generating heat, it’s not so hard to be efficient — you burn a fuel, and most of that energy becomes heat. Not all of it is used well [escapes the building, heats the basement instead of the space you’re in, etc]. But, it does explain why the energy efficiency of our homes is shown to be relatively high.
3. In using fuel for transport, you’ve got two major challenges: firstly, you’re using small explosions to create linear motion which you’ve got to convert to rotational motion. Secondly, you’ve got to move the vehicle itself, and the energy to do that is wasted in that you’re not driving to Stop and Shop to get your car to Stop and Shop — you want to go to Stop and Shop.
4. For electricity, you’ve got a similar problem. You create a fire to heat water, converting it to steam. Then you run the steam through a turbine to convert to a rotational energy. You use that rotational energy to spin a magnet, converting it to electrical energy. Then, you’ve got to transport that electricity across long distances, step down it’s voltage, and then across a short distance, and then step down the voltage again at the location of the appliance. At each transfer you’re going to have losses, and these losses compound. Those first steps — fuel to steam to rotational energy — have very real efficiency limits.
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p>It’s clear that we can be better about home heat both by using the energy more wisely [insulation and air sealing, space heating, zones] and by just using less [programmable thermostat, wear a sweater]. It’s clear that we can be better about transportation fuel both by using energy more wisely [short term: don’t speed, inflate tires, combine trips; longer term: high mpg auto] and by using less [walk, cycle, mass transit]. For electricity, it’s actually a bit tougher to use it more efficiently; Energy Star etc helps a bit, but it’s not so easy to squeeze much more efficiency out of the production and delivery of electricity. We can, however, just use less: CFLs, close the laptop lid, turn off lights, get rid of that refrigerator in the garage/basement, hang clothes to dry, that sort of thing.
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p>Bottom line in terms of carbon emissions: we need to decrease our total use of coal and increase our total use of wind/solar/geothermal/biomass. We need to consume less gasoline. The former isn’t so much of an efficiency issue, but the latter certainly is.
There are also political decisions we can make that would reduce consumption, like higher gas tax, but also reducing programs and the number of workers driving to work (paying people to stay home more), decreasing size of wasteful industries like financial and insurance and medical sectors, etc (censoring porn off the internet would halve internet use).
When Amory Lovins published his visionary Soft Energy paths in the 1970s, then-current trends would have lead to an energy consumption today of about 200 quads, the so-called hard path scenario.
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p>Yet today at 94 quads we are actually very close to the soft path he proposed at the time.
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p>I found both of his classic charts from that work online here.
The top line [total use] is close, but the energy components of that use are different. Also, the trajectory doesn’t seem to be the same — our energy consumption growth has slowed to be sure, but it hasn’t gone negative when corrected for employment.
I didn’t mean we were there yet–in particular, as you note, the slope is positive, and the composition of the area under the curve is not nearly so green.
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p>But looking back, it’s clear that the failure of the mega-schemes, particularly nuclear, in the 1980s created an opening for efficiency which would not otherwise have occurred.
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p>Lovins’s soft-path chart was not predictive but rather prescriptive, an illustration of what would be possible if society began in the mid 70s to eschew the mega-schemes and plan for a sustainable future. We didn’t do that, obviously.
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p>But recall that in the 1970s the President of the United States had just called for 1,000 1,000-MW reactor to be in service by the end of the century, a new one commissioned every twelve days on average. We didn’t do that either, thank goodness.
At some point, don’t we reach an maximum efficiency level, due to physics, in all modes of generation and use?
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p>And don’t new technologies, like electric vehicles, simply rearrange the flow chart? Is it more efficient to use petroleum for cars than to generate more electricity, transmit it, distribute it, transform it, and store it in batteries, then use it to drive electric motors?
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p>Is that any more efficient than drilling, shipping, refining, trucking, pumping and burning oil/gasoline?
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p>One would expect that the petroleum cycle is more efficient at the moment because that’s what the price tells us. (I assume away environmental externalities.)
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p>I know for a fact that wind and solar PV power generation is much less efficient than conventional power generation, wind 3 to 5 times more expensive, and solar up to 50 times. Given their current costs/kwh, neither is likely to play a big role in the energy mix unless and until technological breakthroughs occur.
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p>And I don’t see that happening with wind. Hopefully for PV … it’s ideal for distributed generation.
I guess it could be considered entertainment, but it has a very low entertainment value. If some of the responses had been funnier, it’d be much more efficient. As it stands though, it’s a waste.
Buddhist logic is the core of the poll answers. Experience has taught me to add the last two possibilities. Yes/No thinking is part of our problem.
“Not no” would be saying that more efficiency is fine, but what we really need to do is consume less energy, drive less far, have fewer people driving, download fewer movies, watch less television. So OK I’ll go with “not no” instead of “yes”.
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p>I think prohibiting porn on the internet would double the available bandwidth and storage for other things, meaning we could put off upgrades for a few years, and we could turn off lots of web servers. And if it resulted in more people being incarcerated, that’s fewer cars on the road.