http://mvnm.tumblr.com/post/679443357/surface-area-required-to-power-the-whole-world-by-solar

Have you read the analysis done by David MacKay in his book Sustainable Energy - without the hot air

He also mentions an organization Desertec which has been promoting the idea of large solar arrays in north Africa supplying most of Europe’s needs.

Interesting map. One hidden assumption is that this is entirely solar electric rather than a combination of solar thermal followed by solar electric. Another hidden assumption is that solar means directly from the sun. Jimmy Carter’s definition of solar included indirectly from the sun, which could be generalized as far out as to include oil.

jamesr - 09 June 2010 03:53 PM

Have you read the analysis done by David MacKay in his book Sustainable Energy - without the hot air

He also mentions an organization Desertec which has been promoting the idea of large solar arrays in north Africa supplying most of Europe’s needs.

No I haven’t, but I am already cautioned by his claim of “without the hot air”.
Basically there are 2 camps in energy field - renewable camp and nuclear camp and they are trying to disprove each other all the time.

Breakable - 10 June 2010 01:41 PM

jamesr - 09 June 2010 03:53 PM

Have you read the analysis done by David MacKay in his book Sustainable Energy - without the hot air

He also mentions an organization Desertec which has been promoting the idea of large solar arrays in north Africa supplying most of Europe’s needs.

No I haven’t, but I am already cautioned by his claim of “without the hot air”.
Basically there are 2 camps in energy field - renewable camp and nuclear camp and they are trying to disprove each other all the time.

It is a good book, and goes through all the numbers for each type of renewable step by step (from a UK perspective).  At one point when going through the numbers for nuclear waste he says

Please don’t get me wrong: I’m not trying to be pro-nuclear. I’m just pro-arithmetic.

. 

But at the end when he comes up with 5 plans for the energy mix for the UK, the one where he also regards economic factors ends up with 44kWh per person per day of nuclear out of a total of 50kWh/p/d of electricity produced (see p211).

okay, so that works out to about 2kW per person. given that you don’t get full sunlight all day, let’s say this is equivalent to a 8 kW panel, which costs ~$40k but supposedly operates for 25 year.
.. overall $133/month.

to make this 100% renewable, you want to bootstrap the technology: energy required to make and maintain and dispose of panels would all have to be renewable as well.

Breakable - 09 June 2010 02:57 PM

http://mvnm.tumblr.com/post/679443357/surface-area-required-to-power-the-whole-world-by-solar

Just a little concerned that all of Europe and most of Africa are here powered by Libya. Have you looked at this map from a political point of view. Avoiding just such scenarios is one of the strong reasons for weaning ourselves off of fossil fuels.

(Still, at least the Wold Cup lights would stay on - to all my friends across the pond, good luck in the footy tomorrow )

Any calculations that can be made are currently pretty rough IMHO.
The cost of any technology goes down with time, where the efficiency goes up.
This should be true for PV, CS, transmission, storage costs.
Also the economies of scale can reduce the price a lot.

How much exactly storage, transmission, area or efficiency is required I don’t think is currently clear,
especially when transmission/storage can be interchangeable in some situations as well as efficiency/area.
Maybe for now a maximum cost limit can be calculated, for a single home-based installation in this case I would agree to about ~$5-8 usd/watt (payback 15-30 years),
but it should get better with new technologies (i am betting on roll-to-roll manufacturing for everything - from PV (now) to batteries (later) to control electronics (much later)).
Of course it makes sense for well insolated areas such as Africa, Middle East, Australia, southern USA.

Still probably the best costs can be seen after the implementation stage (for any project).

Also I don’t see a problem for Europe to get most energy from Africa-Middle east, because there would be some competition by energy providers,
home sources (Europe based PV vs Africa based CS), as well as it could make poorer countries richer.

trading power across long distances could work if transmission losses are minimized.

I learned today that, because Ontario’s nuclear generators need to run continuously, Quebec buys off-peak power from Ontario at a substantial discount, stores the energy by pumping water, and then sells power back to Ontario at 4x the rate to cover peak usage.

vansig - 12 June 2010 02:49 AM

trading power across long distances could work if transmission losses are minimized.

I learned today that, because Ontario’s nuclear generators need to run continuously, Quebec buys off-peak power from Ontario at a substantial discount, stores the energy by pumping water, and then sells power back to Ontario at 4x the rate to cover peak usage.

Interesting fact.

There are some ways to minimize the losses for now:
http://en.wikipedia.org/wiki/Hvdc
Later maybe superconductivity will get affordable.
And even for ac grid they don’t seem very high:
http://en.wikipedia.org/wiki/Electric_power_transmission#Losses
Transmission and distribution losses in the USA were estimated at 7.2% in 1995 and 6.5% in 2007

Some discussion of Nuclear vs Renewable’s
http://www.ted.com/talks/debate_does_the_world_need_nuclear_energy.html

Still if FF gets done ~5 years probably most solar will be irrelevant, except for some people who wont be able to afford a fusion generator (Africa?).

So where’s the nuclear fusion in the solar part? I’m afraid I fail to see it.

Actually I’m really curious how solar-driven nuclear fusion can be achieved. A straightforward approach wouldn’t work: bombarding a target of anything with solar radiation would heat it to at most 5600 K, which is the Sun’s temperature and the solar radiation’s temperature too. Concentrating it would not help - the same maximum temperature holds. Yet I would not say it’s impossible to do it.

One way to achieve solar nuclear fusion would be to concentrate solar radiation on a laser. The laser radiation can next be used to achieve nuclear fusion.

Another would be to attempt to do inertial confinement on a fuel pellet with concentrated solar radiation. That way the bet would not go on the heating only.

The fact is solar radiation has a lot of energy and having a way to drive nuclear fusion with it could be very useful.

Any other ideas? Maybe some practical ones? Mine are not very practical, I would say.

You do know that sun is driven by fusion reactions don’t you?

Breakable - 25 August 2010 05:59 AM

You do know that sun is driven by fusion reactions don’t you?

Aaa… it slipped past me.

Well, I guess coal burning can be thought as nuclear fusion energy too, since carbon is formed in stars. Just to stretch it even more.

Anyway, you have a point. My questions still remain: how do we make the bomb with the help of the Sun?

Ferret - 25 August 2010 12:21 PM

how do we make the bomb with the help of the Sun?

Dumping about 10 solar masses into it will produce a doozie of an explosion…

speaking of solar, here is a vimeo video demonstrating just what could be done with all that heat..

http://vimeo.com/25401444