[Marxism] "Major Discovery" From MIT Primed to Unleash Solar Revolution II

[Les Schaffer]

David Walters, et al.:

for what its worth, i am currently consulting on a concentrating solar 
power system (CSP) design ... but CSP simply delivers high temperature 
steam to run a turbine to produce electricity to do XXXX. How CSP would 
relate to this new electrolysis is unclear, no? you claim the 
breakthrough is in storage. but storage is only needed if you want to 
make some fraction of electric users fully dependent on solar.  
otherwise its simply another source of power. and if you store, you have 
to reconvert and transmit later, and we know our transmission 
infrastructure is creaky. now a global transmission system, powering the 
shadow while while the other side sunbathes, that would be something, eh?

but lets grant this breakthrough storage scheme and see what kind of 
area is needed so that solar could fill the tank, so to speak. how many 
square meters of sunny area would be needed, in the US for example, to 
power itself, assuming you *could store* and re-transmit through the 
remaining say 16 hours of dawn, dusk, and night?

well, whats our latest power usage, averaged over 24 hours? from wikipedia:

       http://en.wikipedia.org/wiki/Energy_use_in_the_United_States  

i get about 1,000,000 MW for the electric production rate in 2006.   
(nameplate capacity)

so, lets say we can collect solar energy at 100% efficiency over a third 
of the day and store for the other two thirds of the day. then we need 
3,000,000 MW of instantaneous production.

3,000,000 MW / (1.4 kW / m^2) = 3,000,000 / .0014  (m^2) = 2,142,857,143 
(m^2) = 825 sq miles (= 530,000 acres)

this sets the *scale* for solar-electric production without revolution 
in the way we live. that is 825 square miles of the earth's brightest 
surface blanketed with solar collectors, connected to electrolysis or 
energy storage of your choice and re-transmitted now or later.

interesting number. not quite as fearsome as i first guessed, but plenty 
big... everything 100% efficient, nothing but the best for us .... ;-)

you can play with the numbers. you want to promise us some clean/safe 
nuclear, take some fraction of 824. want to keep burning coal but at a 
reduced rate? reduce it some more. and so forth. want to reduce electric 
consumption by half? want to leave the others forms of production and 
just eliminate coal-fired, thats 400 sq miles then. you think we can 
collect for 12 hours of the day in New Mexico?:  500 sq miles. etc etc 
etc ...

for the quibblers amongst us: when i say that 825 sq miles sets the 
scale for solar-electric production, it means its an order of magnitude 
estimate. if the wikipedia #s are wrong or misleading, the point is to 
set the gross scale at which one would need area for solar power 
collection at the 1.4 kW/m^2 intensity. if you come up with 325 sq miles 
or 1600 sq miles, its only incidental.

andy pollack: did this answer your question, or do we need more details 
on collectors and efficiencies and all that? can someone like the 
railroad man make an estimate of the cost (materials, labor, 
environmental) to produce say 100 square miles of x% efficient collectors?

by the ways:

1. someone pointed out on a blog that the water usage for this new 
conversion scheme would be large.

2. the wikipedia #s give us (potential) electric production as of two 
years ago, not total energy use.

3. that wikipedia article above states there is about 400 MW of solar 
electric generation in the US in 2006. i don't know if that is daily 
average or what. but that requires about 0.1 sq miles of existing 
collector surface area. so we have at least three orders of magnitude to go.

4. Rhode Island has 1545 sq miles. so half of Rhode Island.

to sum up, storage of solar energy is a piece of the puzzle, but only a 
piece, and not the most important piece. to keep things as they are 
(consumption-wise), supply must equal demand.  in power this is true. 
storage is a detail. so the MIT claim is hype, though the prof has come 
up with an interesting and potentially useful technology.

Les