Re: [Phys-L] CLIMAT a post from another list:

[Richard Tarara <rtarara@saintmarys.edu>]

On 12/14/2015 2:09 PM, Ludwik Kowalski wrote:
> If you allow me to carry my cynicism a bit further, I would describe the Paris agreement about climate change as a fig leaf. It allows everyone to continue doing what they want while being able to say they tried to stop the seas from rising. They can say to the people being drowned, "we did our best, so stop complaining".  Meanwhile, fossil fuels will be phased out only as fast as is convenient and economically beneficial, as would have been the case without the agreement.  Meanwhile, everyone can be happy for a little longer.
>
> Ludwik Kowalski (see Wikipedia)
>
> =============================================
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What nobody wants to come to grips with here is that we really don't 
have a way to provide the 2-3 times today's world energy use without at 
least some (actually lots) of fossil fuel use.  World demand is going to 
keep increasing with the development of China and India and possibly 
sub-Saharan Africa through this century.  Keep in mind (which the media 
often doesn't) that eliminating the fossil fuels means a lot more than 
replacing coal-fired electrical plants since transportation, heating, 
and industrial energy use makes up well over 50% of the current demand.  
We might get most of the current electrical usage from renewables, but 
getting all our energy at year 2100 demand levels really can't be done 
with biomass, wind, and solar....at least not without major 
technological advances.  Keeping nuclear in the mix is a short-term 
solution without breeder technology.  OTOH, Europe and even the U.S. 
have been moving to better energy efficiency and more and more renewable 
usage.  The U.S. IS the largest producer of wind energy today (China has 
more installed capacity but less actual output), but it is telling that 
none of the large wind farms now running can stand alone, be primary 
energy sources.  Most obviously the problem is what happens on the day 
the wind doesn't blow.  The operational efficiency of those farms now in 
operation is not much better than 30% which makes the typical 1.5 MW 
wind turbine effectively a .5 MW unit when integrated over a year.  To 
match the energy output of a typical 1000 MW coal/gas/nuclear plant then 
requires a couple thousand units--and that's just one plant equivalent.  
IMO, this is the primary problem that has not really been addressed.  
How to make large wind and solar systems 'energy on demand' systems 
without having to have almost as large a backup network of fossil plants 
in reserve.  That kind of system could work technically, but might not 
work economically, at least not with energy being supplied by private 
energy companies.  If we can't come up with a viable energy storage 
system (hydrogen is a possible option here) then the path to fossil free 
energy really might require major changes in economic and political 
models...something that will take time to transition into....time we may 
or may not have!

rwt

--
Richard Tarara
Professor Emeritus
Saint Mary's College

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