Thursday, May 2, 2013

Thursday Links

  • We're about to cross 400ppm of carbon in the famous Mauna Loa measurement series.  399.5 ppm today.  If you look at the monthly graph, there have been some hourly averages that have tipped over the line.
  • Storage options for renewable power (nice summary by Robert Rapier).
  • Bakken recoverable oil estimates are growing again.  At a 5% depletion rate, 7.4 gb gives about 1mb/d of production.
  • Completely off-topic, but it really sounds like scientists are starting to get somewhere with cancer.  Pretty exciting stuff.
  • Speaking of amazing but off-topic medical progress: possible new understanding of aging being regulated by the hypothalamus.  I've had a strong suspicion that aging must be centrally regulated just from reflecting that dogs and cats get a lot of the same chronic diseases as humans, just on a much accelerated timeline, suggesting they are somehow part of the normal aging process.
  • Hopefully, scientists will get on this stuff promptly before I get too much older (although, I have to admit very uncharitably that I'm hoping not before Ray Kurzweil gets too old).

5 comments:

Nick G said...

It seems obvious that there is an aging clock.

Compare typical rates with naked mole rats that live 10x longer, and bats with similar size and body shape which live 15x longer.

And, yes, 50kg dogs that live 10 years, chimps that live 50 years, and 50kg humans that live 100 years.

Another clue: menarche and menopause are clear signs of a developmental/aging clock.

sunbeam said...

"Speaking of amazing but off-topic medical progress: possible new understanding of aging being regulated by the hypothalamus. I've had a strong suspicion that aging must be centrally regulated just from reflecting that dogs and cats get a lot of the same chronic diseases as humans, just on a much accelerated timeline, suggesting they are somehow part of the normal aging process."

I'm definitely not a biologist, but I would think this unlikely to be so simple.

Mutations happen all the time. Someone, somewhere, would have had some mutation that altered this organ in such a way as to have an extended lifespan.

Aside from being the plot of a science fiction story, let's play devil's advocate with this.

Maybe they could potentially have lived a very long time, but got killed by something other than old age (very common).

Maybe they got burned as a witch or sorceer.

But considering that this site (http://www.prb.org/Articles/2002/HowManyPeopleHaveEverLivedonEarth.aspx) says 6.5% of the 108 billion people who have ever lived are alive now, you'd have a decent chance of one being around somewhere now.

We'll have to wait and see, but as a layman I'd think there is more than one thing going on with aging.

Of course it if it so simple, just imagine an eternity shared with Bill Gates.

Kurzweil better get on the ball, because I want to drop out and live out my eternal life in a fantasy world sim as a wizard.

Nick G said...

Sunbeam,

There are multiple possible reasons for natural selection away from infinite lifespans. There is a need for random remixing through reproduction, plus lifespans in the wild are very short due to predation, accidents and illness, so the E-ROI of a long lifespan (before the Industrial Revolution)is low.

Nick G said...

I looked at Robert's article on storage, and added the following comment:

This topic is way too big to cover in a single, general article. Nevertheless, there is one level of detail that needs to be included, namely that there are several very distinct and different markets for storage. It confuses things enormously to mix them together.

There's the need for extended seasonal storage, when both wind and sun are low for several weeks. That requires very low capital costs to provide a large capacity, but efficiency isn't very important, as it would only provide 5% or less of the annual kWhs supplied. Hydrogen is perfect for this, either mixed with methane, or stored underground. These are well proven technologies. On the other hand, we may need much less of it than one might think, as other cheaper strategies may solve most of the problem, including Demand Response (aka Demand Side Management), weather forecasting, long distance averaging, V2G, etc, etc.

There's the need for daily storage, to deal with daily variation. That needs high efficiency, as the percent of power than is cycled through it will be higher. On the other hand, it's maximum capacity will be much, much lower, so it can accept higher capital costs. Batteries will work well for this, particularly those already sold as part of EVs. Pumped storage is an obvious solution for this, and hydrogen (despite lower efficiency) might work as well. This area will be very dynamic in years to come.


Finally, there's personal transportation, which needs high energy and power density, and can accept high capital costs. Here batteries will do well, and hydrogen is a non-starter.

Anonymous said...

What's up with the remark about Ray Kurzweil? I take it you have a strong disagreement with him on some issue? If so, I'm curious as to what it is.