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The Energy Oath: In Production and Use Do Good or No Harm

The physician must be able to tell the antecedents, know the present, and foretell the future — must mediate these things, and have two special objects in view with regard to disease, namely, to do good or to do no harm.”  Hippocrates.

He said this in Of the Epidemics written in 400 B.C.E as opposed to the Hippocratic Oath to which it is more widely attributed.

Regardless of its origin, “to do good or to do no harm” is an excellent maxim to follow with respect to the production and use of energy, which is fundamental to the quality of modern life, or for that matter virtually any enterprise.

Increasingly it is becoming clear that in our extraction, production, transportation and utilization of existing energy sources that are in the main finite we are doing considerable harm to our environment.

As the following Wikipedia diagram shows our renewable energy options are extensive and our global consumption modest by comparison. Even if we were to quadruple our current consumption in order to provide all 10 billion people on the planet by 2050 the level of energy prosperity we in the developed world are used to.

 

Clearly solar power is the most abundant. As Wikipedia points out, almost all of our energy comes from the Sun; the exceptions being tidal, nuclear and geothermal power.

Wind comes from the uneven heating of the earth’s surface, and can provide about 1% of the energy that is available from solar power.  

Solar power is more predictable than wind but more variable considering it is not available at night and limited by cloud cover. Nevertheless the Scientific American article A Path to Sustainable Energy By 2030 suggests that at least 580 TW of solar power can be produced.

Thermal energy and pumped energy storage have been suggested as ways to overcome the intermittence of wind and solar.

Global warming is the most significant consequence of current energy use and as the following graphic indicates is a problem of thermal energy storage, mostly in the world’s oceans.

 

Logic dictates therefore that it is this excess energy that we should be depleting by putting it to productive use or at least moving to a location where it can do the least damage.

The consequence of upper ocean heat storage are; thermal expansion and sea level rise, the melting of polar icecaps leading to more sea level rise, increased concentrations of water vapour in the atmosphere, which arguably leads to more intense storms, and potentially catastrophic temperature increases of as much as 4oC by the end of this century.

We can do good for the planet by converting some of the upper ocean energy to at least as much power as we derive from fossil fuels by the process of ocean thermal energy conversion and in the process move about 20 times more heat into the deep ocean that has both a great capacity to absorb heat.  In the process this will decrease the intensity and possibly the frequency of tropical storms.

In his 2006 State of the Union Address, George W. Bush stated, “America is addicted to oil.”

All addictions are destructive.

A pledge to stay sober for today is a common refrain amongst addicts. The rationale is; if I stay sober today, I don’t have to drink for the rest of my life because it’s always today.

Getting off fossil fuels will not be easy. Weaning ourselves day by day is the only way we will get to where we need to be but for every terawatt we get rid we will have to find two to four times as many terawatts from sustainable sources.

Energy is hugely important as is its impact on the next nine most significant problems we face.  

There are not however that many ways to do good while producing energy so we must start maximizing the impact of those that are available to us as rapidly as possible.

It is long past time we took the pledge to do good AND do no harm as we produce and use the energy we need! 

Content Discussion

Clifford Goudey's picture
Clifford Goudey on January 11, 2014

Jim, can you point us to your source on seawater thermal coefficient of expansion vs pressure (depth)?  Your statement seems to disagree with what is portrayed at: Thermal Properties of Sea Water http://publishing.cdlib.org/ucpressebooks/view?docId=kt167nb66r&chunk.id=d3_4_ch03&toc.depth=1&toc.id=ch03&brand=eschol

I’d also submit that the first step in confronting AGW is not finding ways to hide the excess heat but instead to remedy the imbalance in the atmosphere caused by excess CO2 and methane.  I like the idea of OTEC and hope that at some point it will be competitive with other renewable sources. 

Jessee McBroom's picture
Jessee McBroom on January 11, 2014

Thank you for the post Jim. I believe the Hippocratic Oath has its place in life in general. Your closing sentence is very good advice.

Clifford Goudey's picture
Clifford Goudey on January 11, 2014

Jim, but your contention was that the deep ocean has “a coefficient of expansion less than at the surface.”  In fact, the coefficient of thermal expansion increases with depth and what the table is showing is that it decreases with temperature.  It’s an important distinction since the warm water you pump down mixes with the cold water that is already there and the mixture ends up at some mass-averaged higher temperture.  Bottom line is you would be exacerbating the expansion and acelerating sea level rise. 

I accept your two points regarding the value of reducing surface temperature (storm intensity and calthrates) but there is a fourth factor that seems missing: the value of radiative cooling of warm surface water at night.  A fifth possible consequence that to date seems unquantified is the ecological impacts of those thermal plumes and the consequences of entraining biota.

Clifford Goudey's picture
Clifford Goudey on January 11, 2014

Jim, I don’t mean to harp on this, but that graph is of seawater with an “average temperature profile” not at constant temperature.  I therefore maintain my opinion that OTEC does not ameliorate sea-level rise and indeed does the opposite.  I have insuffiecient expertise in the atomic structure of H2O to explain why its coefficient changes the way it does.  Maybe someone else has thoughts.

Clifford Goudey's picture
Clifford Goudey on January 11, 2014

Jim, I’m afraid I have to agree with Hank.

Clifford Goudey's picture
Clifford Goudey on January 12, 2014

Jim, that was not my point.  My point was that it’s no cure.  Heat is being pumped into the deep ocean by various means and because of the positive relationship between seawater’s thermal coefficient of expansion and pressure, the resulting effect is a greater volumetric expansion of warmed seawater at depth compared to it staying at shalow depths.  The ocean need not become isothermal for this, as a thermal expansion of any layer of the ocean results in sealevel rise.  It is germane only because you’re claiming a bonus benefit of OTEC.  It’s not. It’s likely a disadvantage but I am not saying it outweighs the other potential advantages of OTEC being a carbon-free source of baseload power. 

Clifford Goudey's picture
Clifford Goudey on January 12, 2014

I see it as the safer path.  There may be more to this than either of us understand and I wish others with more relevant insights would comment.

Keep up the good work.

Clifford Goudey's picture
Clifford Goudey on January 13, 2014

Jim, merely to affirm the consensus, the matter of the way the thermal coefficient of expansion varies with temperature, pressure, and salinity in not a simple one (though it may be to Dr. Vermeer) so my earlier concerns over the moving of warmer water into the depths was unfounded and the result is not opposite to what Jim had claimed.  The magnitude of any benefit remains unclear and I agree with Jim’s plan to deemphasize its potential impact. 

Here is the revelation that cleared things up:

Now, let’s say the surface water started out at 25˚C and was kept insulated during its descent and the water at depth was 5˚C.  In the simple case where we allow two equal volumes to mix, the resulting volume would be at roughly 15˚C.  So in this scenario, one volume at 2,000m went from 5˚ to 15˚C while the other volume at the same depth went from 25˚C to 15˚C.  The former volume did so with a TCOE that went from 157 to 241 while the latter volume did so with a TCOE that went from 313 (an extrapolated value) to 241, which means that the latter contracted more during the temperature change than the former expanded.