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Cheap Solar Power

keith.seas.harvard.edu

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Re: Cheap Solar Power

#81

Post by epistasis »

beat wrote: post #78
epistasis wrote: post #48

Earlier quoted context omitted.

That's a biofuel, not a synthetic fuel. The difference being biological process versus a chemical synthesis process. BTW, I accidentally downvoted you, did not mean to! Sorry for the loss of an internet point. It wasn't mean to discourage your comment.

Synthetic fuels have it even worse, I think, in terms of cost. Unless we can get a really cheap form of electricity that is clean (solar) and connect it to a process that it more efficient than simply growing corn (or other biomass), then synthetic fuels will have the same problem. They can't be cost-competitive with fossil fuels without massive subsidy.

Yeah, I agree. Making hydrogen, the first step for pretty much any synthetic fuel, is exceedingly inefficient. That means that transmitting electricity long distances is usually going to be much more cost-effective than making liquid fuels.

But I think that as electricity gets cheaper and cheaper, and as fossil fuels have a pigovian tax levied on them, that eventually synthetic or biofuels will be more cost effective than fossil fuels. Electricity is going to get super cheap, and there's going to be times when supply outpaces demand. If the electricity would go to waste otherwise, something that's 40% efficient may be a good use of it.

Re: Cheap Solar Power

#82

Post by xrange »

djrogers wrote: post #71

I really have to take exception with a statement in the opening here: > rooftop solar seem systems which are (arguably) little more than green bling for the wealthy My rooftop solar system (installed in late 2013) is 2.5 years in to what is looking to be a 5.9 year break-even point. After 6 years I will be earning $4-5k/year from it. Even if I had financed this (not a solar lease, those are usually structured so the…

>After 6 years I will be earning $4-5k/year from it.

Can you point us in the direction of a good write-up on net-metering? I'm sure different jurisdictions have different rules. I was under the impression that net metering was only good up until your yearly production was equal to your demand. Or are you saying that the $4-5k/year is at wholesale rates?

Re: Cheap Solar Power

#83

Post by semi-extrinsic »

dougmany wrote: post #43
swsieber wrote: post #28

Earlier quoted context omitted.

So, really, if one wanted to fix CCS, you would just need to find a good application for CO2, like with peanuts and peanut butter.

I like the idea of making carbon fibers from CO2. http://www.acs.org/content/acs/en/pressroom/newsreleases/201...

Sure, there are many interesting things you can make from CO2. The problem is the sheer amount of CO2 we need to capture and store, which utterly dwarfs the production volumes of basically anything you can think of.

We're talking hundreds of gigatonnes of CO2 that have to be stored over a century of CCS. At high temperatures and pressures, when the CO2 is in a dense (supercritical) state, as in geological storage formations, this corresponds to hundreds of billions of cubic meters.

It's a thousand Hoover dams each year full of dense phase CO2. It's truly mindboggling.

Re: Cheap Solar Power

#84

Post by maxerickson »

_FKS_ wrote: post #68

In the meanwhile, a few other sources argue that the overall ERORI (energy invested vs. energy produced) is well below a somehow 'sustainable' level. The impression I'm getting is that the day oil/gas production starts to fall due to geological limits, so will the production of photovoltaic & windmills. Please see: https://collapseofindustrialcivilization.files.wordpress.com... And: http://science-and-energy.org/wp-c…

The first link is about installing panels in regions of moderate insolation like Germany. Areas with more sun make more sense.

Re: Cheap Solar Power

#85

Post by [deleted] »

_FKS_ wrote: post #68

In the meanwhile, a few other sources argue that the overall ERORI (energy invested vs. energy produced) is well below a somehow 'sustainable' level. The impression I'm getting is that the day oil/gas production starts to fall due to geological limits, so will the production of photovoltaic & windmills. Please see: https://collapseofindustrialcivilization.files.wordpress.com... And: http://science-and-energy.org/wp-c…

[deleted]

Re: Cheap Solar Power

#86

Post by xrange »

ck2 wrote: post #73

Imagine an earth 1000 years from now where countries on one side of the planet help out the other side via solar power through superconducting power cables that have little power loss over 10,000 miles. Since each side gets sunlight somewhere, no batteries needed. Of course 1000 years from now they could solve the battery problem too where each residence has its own low cost, safe storage. Or 1000 years from now terr…

>Or 1000 years from now terrorists dirty-bomb everyone.

...Well, on a more optimistic note, a dirty-bombs, while they may destroy property values and cause cleanup issues, don't really kill any more than a conventional/kinetic bomb. I think they may be one of the best-case scenarios when it comes to a terrorist strike, since the causalities will be low, but there will be a lot of "frenzy" about the invisible radiation. (I'm sure someone will correct me if I'm wrong, or if there are silent aerosolized short-half-life "bombs" in existence that are "detonated" secretly inside of buildings so that people are accumulating long term exposures unknowingly).

Also, I wouldn't be surprised if room-ish temperature superconductors appear much sooner than 1,000 years from now. And it will definitively be interesting to see how high of energy densities SMES (Superconducting Magnetic Energy Storage) will get to in the next 20 years with existing cryogenic superconductors.

http://snf.ieeecsc.org/abstracts/stp443-high-field-hts-smes-...

Re: Cheap Solar Power

#87

Post by marcosdumay »

_FKS_ wrote: post #68

In the meanwhile, a few other sources argue that the overall ERORI (energy invested vs. energy produced) is well below a somehow 'sustainable' level. The impression I'm getting is that the day oil/gas production starts to fall due to geological limits, so will the production of photovoltaic & windmills. Please see: https://collapseofindustrialcivilization.files.wordpress.com... And: http://science-and-energy.org/wp-c…

If solar power is cheaper than coal without subsides, it has greater than 1 EROEI by a big margin, and the question is settled.

Bottom-up studies suffer from a big diversity of flaws, and there are plenty of them with obvious bias both ways.

Re: Cheap Solar Power

#88

Post by djrogers »

agumonkey wrote: post #59
amalantony06 wrote: post #27

Given that Solar power is the fundamental source of energy leading to petroleum based energy (starting with photosynthesis), it's surprising that we still rely on petroleum to the degree we do today. In 100 years this would perhaps be something people would find shocking (like how we are shocked today at how mainstream slavery used to be 150 odd years ago). Solar Energy is unlimited, cheap and clean. My guess would b…

Because history made us build structures and lifestyles that require oil class energy density. We surely don't need it since we were born without. We don't need all of this. Not to that extent, we could cut worldwide transportation. We could eat less. Rethink housing. Even internet[1]. I'd like to see the time when energy will lack. Sometimes I wonder how we could rebootstrap technology in a frugal manner. Have shelt…

> just the other day I put a gif on imgur, 1Million views, a few TB of bandwidth..

Umm, exactly how big was that gif? One of those numbers doesn't match up with the other...

Re: Cheap Solar Power

#89

Post by djrogers »

xrange wrote: post #82
djrogers wrote: post #71

I really have to take exception with a statement in the opening here: > rooftop solar seem systems which are (arguably) little more than green bling for the wealthy My rooftop solar system (installed in late 2013) is 2.5 years in to what is looking to be a 5.9 year break-even point. After 6 years I will be earning $4-5k/year from it. Even if I had financed this (not a solar lease, those are usually structured so the…

>After 6 years I will be earning $4-5k/year from it. Can you point us in the direction of a good write-up on net-metering? I'm sure different jurisdictions have different rules. I was under the impression that net metering was only good up until your yearly production was equal to your demand. Or are you saying that the $4-5k/year is at wholesale rates?

If I'm not paying that $4-5k to PG&E, and the installation costs have been recouped, then that $4-5k/yr is profit. Money is fungible - if you manage it well, you get the same net effect from preventing it's loss as you do from earning it.

Re: Cheap Solar Power

#90

Post by djrogers »

thrownaway2424 wrote: post #39

When will this "duck pricing" actually trickle down to consumers? I'm on a PG&E rate plan that charges me an incredible $0.75/kWh during the afternoons of selected days. According to the figures in the CAISO paper, these are the hours of least net demand.

>I'm on a PG&E rate plan that charges me an incredible $0.75/kWh during the afternoons of selected days.

Yeah, PG&E is practically begging their customers to install solar. The biggest savings come on the days/times with the best solar potential, and dropping out of that highest tiers can be a real win.

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