Energy • Hacker News Board

Re: Energy

#151

Post by Retra » Tue, Jun 30, 2015, 1:00 AM UTC

someguy488fu348 wrote: post #134

beat wrote: post #22

Earlier quoted context omitted.

Decentralization solves a lot of other problems as well - it's less vulnerable to accidental or intentional failure, it requires much less skill and expense to implement and operate, etc. Solar has the advantage that it cannot be weaponized even in nonsense theory, greatly relaxing export regulation. This makes it a viable solution for developing countries and remote areas, not just the handful of nations with the we…

Solar may have been weaponized as early as 214 BCE.

You bring solar weaponry into a modern military battle and see how that works out for you.

Re: Energy

#152

Post by dredmorbius » Tue, Jun 30, 2015, 1:02 AM UTC

gumby wrote: post #142

jfoutz wrote: post #136

Earlier quoted context omitted.

Rather than batteries, i think pumping water up a hill will be a lot cheaper. use the water to drive a generator. massive daily over production to fill the nightly (or much longer) reserve.

That is the state of the art for energy storage today and basically all the sites are taken. Sure, if energy costs go up a LOT a few more will become viable, but if you look around, for example, Californa, it's hard to find another viable site.

Seawater lower basin adds considerably to site count.

There are other concerns: elevated highly variable salt water ponds and wetlands, and general nastiness of saltwater engineering: corrosion and marine life growth especially.

But generally, pumped hydro is really hard to beat.

Re: Energy

#153

Post by slyall » Tue, Jun 30, 2015, 1:05 AM UTC

jfoutz wrote: post #136

beat wrote: post #20

I suspect solar (including wind/biomass) + batteries is going to trounce fission reactors in the not terribly long term. If you think of finance in terms of latency/bandwidth (a model I use for lots of things), reactors are high latency - they're expensive and take a long time to set up. Meanwhile, solar/wind is heading toward dirt cheap and trivial to set up. Environmental impact is minimal, too. It doesn't require…

Rather than batteries, i think pumping water up a hill will be a lot cheaper. use the water to drive a generator. massive daily over production to fill the nightly (or much longer) reserve.

Pumped storage is hard to scale down and has a fairly fixed loss. There are a bunch of other storage technologies that are at the "almost there" stage though. I personally like the Pumped Heat storage from Isentropic as a possible mainstream contender:

http://www.isentropic.co.uk/

Re: Energy

#154

Post by dredmorbius » Tue, Jun 30, 2015, 1:09 AM UTC

jsprogrammer wrote: post #141

donttrustatoms wrote: post #132

Earlier quoted context omitted.

That makes sense given those numbers tabulated, but the real question is cost of solar plus backup or storage. One means nothing without the other in terms of both cost and carbon. Above I illustrated my calculations on just one hour of battery backup for US grid with lithium ion- would require 10x annual global production of lithium. Generally cost of battery backup looks like 35c/kWh and has limitations on duration…

Lithium ion makes no sense for storage. Something like large-scale flywheels would probably be much better. Using gravity for storage is even more sustainable. Flywheels for night use and stored water for long term use (storms, fog, prolonged winter at poles [would need to keep from freezing]) all powered by solar or other low-ongoing-input sources should provide a pretty nice environment.

Flywheels have proved extremely expensive with massive engineering challenges. When you have to account for precession due to Earth's rotation, things get tough.

For short term very high flux power conditioning they've got uses. For long-term storage not so much.

Seconds to minutes is likely their effective range. Not hours to days.

Re: Energy

#155

Post by 3pt14159 » Tue, Jun 30, 2015, 1:10 AM UTC

Probably not. Energy isn't really what is holding the poor back - a lack of stability and security are. If I had to chose one technological improvement to help most people on the planet it would probably be benevolent AI, which could refocus many of our challenges to what is important. Getting people out of poverty and war.

Energy is a tiny component of modern civilization.

Re: Energy

#156

Post by dredmorbius » Tue, Jun 30, 2015, 1:19 AM UTC

nosuchthing wrote: post #73

Least we forget: Tidal energy & Geothermal energy...

Tidal offers little potential at tremendous cost and impacts. Outside a very small number of modest sites, it's not likely to see much application.

Wave power is even worse.

Geothermal from high-flux sites does work and works well, though its limited to a relatively small number of regions worldwide. Many of those have already developed much of the available potential. Iceland, Indinesia, Japan, Kenya, New Zealand, the Philippines, and the United States most notably. Kenya's Rift Valley is probably the biggest greenfield opportunity with significant impact opportunity (Kenya's existing electrical infrastructure is minuscule). In the US, resources generally exclude both the Yellowstone Caldera and Cascade range.

Re: Energy

#157

Post by Thiz » Tue, Jun 30, 2015, 1:19 AM UTC

snowwrestler wrote: post #130

Eleutheria wrote: post #18

Distributed generation is where we should invest. Energy independence for the individual. Individual solar panels and batteries, personal windmills, personal reactors, etc. Imagine all the savings in infrastructure for energy transportation and reinvestment in other sectors. Imagine all the possibilities if people could switch their energy generation model as simple as buying a new product and installing it at home.…

True energy independence goes both ways, which very few people are willing to accept. People will install solar panels and enjoy not writing a check to the utility every month. But if their home battery breaks during a heat wave, they're not going to sit in an un-air-conditioned house and and think, "well at least I'm independent." No, they're going to expect the grid to send them power when they need it. So while in…

They'll go to Walmart to buy a replacement the same day just like they would replace any home appliance.

By that time, I bet batteries would sell for less than a thousand, much less.

Re: Energy

#158

Post by sremani » Tue, Jun 30, 2015, 1:29 AM UTC

I am convinced LFTRs are the way to go, they fit in with distributed generation model very well. For what it is worth 21st if it takes Nuclear turn will be clearly fission, actually fission is good enough. But if we were to ascend into space and beyond fusion gives us bigger wings.

Re: Energy

#159

Post by icanhackit » Tue, Jun 30, 2015, 1:30 AM UTC

beat wrote: post #20

I suspect solar (including wind/biomass) + batteries is going to trounce fission reactors in the not terribly long term. If you think of finance in terms of latency/bandwidth (a model I use for lots of things), reactors are high latency - they're expensive and take a long time to set up. Meanwhile, solar/wind is heading toward dirt cheap and trivial to set up. Environmental impact is minimal, too. It doesn't require…

think of finance in terms of latency/bandwidth [...] reactors are high latency - they're expensive and take a long time to set up

I like this metaphor. I think what you might have implied but didn't explicitly mention was distributed vs centralized when thinking about these systems as well. Solar can be a distributed system whereas fission & fusion systems are centralized.

Even though you can make small fission systems and IIRC Skunkworks is working on a small fusion reactor (small = fits on freight truck...once the damn thing works) you still have issues with waste, heat, faults etc. so they need to remain isolated from living space. Thus they are better utilized in a centralized manner.

Sticking with the computer/internet metaphors, you could consider solar to be like a Solid State Drive while fission is very much the classic HDD, moving parts and all. The elimination of moving parts/complexity to generate electricity makes solar suitable for the home just as NAND is better for portable devices like phones.

Pros: speed vs capacity, Cons: cost vs complexity - pick one from each pile.

Re: Energy

#160

Post by Thiz » Tue, Jun 30, 2015, 1:30 AM UTC

thesteamboat wrote: post #133

beat wrote: post #22

Earlier quoted context omitted.

Decentralization solves a lot of other problems as well - it's less vulnerable to accidental or intentional failure, it requires much less skill and expense to implement and operate, etc. Solar has the advantage that it cannot be weaponized even in nonsense theory, greatly relaxing export regulation. This makes it a viable solution for developing countries and remote areas, not just the handful of nations with the we…

> Decentralization [...] requires much less skill and expense to implement and operate, etc. This isn't true because decentralization is easier, it's true because technologies which this isn't true of (require large capital expenditures or high degrees of expertise) can't be given to everyone and their mother. By saying we're doing decentralized X we're moving the problem of requisite operating skill to the designers…

I believe the most important unobserved benefit from decentralized solutions is the wave of innovation it would spark.

Private moneys would compete for a slice of the pie bringing to market millions of ideas putting the pedal of progress to the metal.