An image of Kardashev scale projections ranging from 1900 to 2100. The projections are off by 0.1 on the kardashev scale. This is graphed against the supportable population and given growth against the supposed technology growth associated the kardashev scale. Projections are made by different ratios of energy production to technology growth for a given level of energy (and technology) against predicted population growth, and new technology production and new energy production needed to support a given population, and the growth of such population. In some projections, if energy production is unable to keep up with population growth, technology levels fall. In some projections, as population growth slows, supposedly increased technology can be produced via the lower amount of energy needed to sustain population growth.
<p><b>Outside comment</b> : It appears much of the data were taken from International Energy Agency, <a rel="nofollow" class="external text" href="http://www.iea.org/textbase/nppdf/free/2005/weo2005.pdf">World Energy Outlook 2005</a>, pg. 82, according to <a href="https://en.wikipedia.org/wiki/User:Sparkygravity" class="extiw" title="en:User:Sparkygravity">User:Sparkygravity</a>. The following is an incomplete legend of lines plotted, with completeness to follow once all original acronyms can be deciphered:
</p>
<ul><li><i>POP. PROJECTION</i> (thick violet): Population projection data with no data points, interpolated (smoothed).</li>
<li><i>POG</i> (unknown, dark gray?): Unknown acronym, may not have been plotted.</li>
<li><i>PBM</i> 1973, 2002, etc. (all other solid lines): Refers to original extrapolations of energy consumption based on above data (as the data only go to 2030), also apparently scaled to the projected population or "new energy production needed to support a given population". The projections are all approximately on the same curve, suggesting that the variations may only be in the fitting curve. See description for precise quote and evidence for original research, as well as further discussion on the talk page.</li>
<li><i>FDT</i> and <i>RDT</i> (dashed green and blue): The first letter is undetermined, but the second pair refers to "doubling time". The straight lines have slope proportional to doubling time, which reflects a simple power law on log-log scale, with the power law presumably taken from the same IEA source. Doubling time is a simple exponential scale factor, <a rel="nofollow" class="external text" href="http://nextbigfuture.com/2009/04/projecting-250-years-to-star-trek.html">a statistic applied in many simple extrapolations as here</a>.</li>
<li><i>PO PROJECTIONS</i> (dashed orange): Peak Oil projections in the above data and possibly elsewhere, as many sources have extended projections through 2100.</li>
<li><i>POP-TECH GAP BVP</i> (dashed red): This has no clear source, though the "technology gap" is a term used in other government sources referring to the difference in industrialization between 1st-world and 3rd-world nations. This interpretation, however, seems irrelevant to the subject at hand.</li></ul><p>Note that there are no units given for any such plots, though the population projection probably aligns on the right and another user <a href="https://en.wikipedia.org/wiki/Talk:Kardashev_scale/Archive_2#Comments_and_questions" class="extiw" title="en:Talk:Kardashev scale/Archive 2">has suggested</a> that the energy "PBM" scales are converted from IEA data on the left. This makes the combination of logarithmic and linear vertical scales, as well as population and energy scales, on the same axis questionable at best, but more likely useless and confusing, and therefore should likely be cleaned up if this image is to retain any usability.
</p>
Many articles and reproductions online (notably <a href="https://en.wikipedia.org/wiki/Technological_Singularity" class="extiw" title="en:Technological Singularity">Technological Singularity</a> have vastly misinterpreted this graph in thinking that <i>all</i> lines are Kardashev-scale projections, which has been shown to not be the case. Only the dense cluster of lines are projections relevant to the left-hand Kardashev scale. It is therefore recommended that captions be changed and this image not be used further in any encyclopedia articles for ongoing ambiguity, original research, and confusion in plotting.
<a href="https://en.wikipedia.org/wiki/User:Ctrl_build" class="extiw" title="wikipedia:User:Ctrl build">Ctrl build</a> at <a href="https://en.wikipedia.org/wiki/" class="extiw" title="wikipedia:">English Wikipedia</a>
CC BY-SA 3.0
Transferred from <span class="plainlinks"><a class="external text" href="https://en.wikipedia.org">en.wikipedia</a></span> to Commons.