// I haven't watched the video. Would love to see a text version thereof if it exists.

Is it per unit of power that can be produced under optimal conditions or per unit of power averaged over a year? Note that half of the time in a year it's dark, so in order to produce the same amount of energy in a year you need a solar power plant with at least 2x power rating of a power plant that can operate continuously.

Does this include the cost (monetary (capital) and in additional energy that has to be generated due to storage losses) of storing the energy over periods of darkness and inclement weather?

This also means you need 5-6 times the amount of transmission infrastructure compared to if you have centralised power generation that can be rapidly scaled up and down. Burning coal is one such solution (obviously a terrible one given climate change). Gas is good for intermittent 'peaker' plants, but it's not exactly cheap nor co2 free.

Contrary to what's being said above, I think fission absolutely must be explored to avoid a climate catastrophe. Our current fission reactor tech is basically the same tech we had in the 50s and 60s, which manages about 3% fuel efficiency (mostly due to the use of solid fuels). Despite this, it's still at least 'in the ballpark' cost-wise, and also the second safest form of power generation, according to the IPCC, over its entire life-cycle (from mining to waste disposal and remediation). Incidentally, hydro is the first.

If we could invest even just a little bit of money into furthering fission research, we could very well end up with an abundant, cheap and safe method of generating baseload power. Or we could yammer on about the cost of 'political capital' and accept a much higher probability of extinction because a section of the population are either misinformed or just flat out ignorant. Yeah, let's do that.

Do you think grid-level energy storage needs to be batteries, as opposed to other forms? If so, why?

Come to think of it, I've only ever looked at the per KW hour cost of batteries (lead-acid seems to be the clear winner). You wouldn't happen to have references for other energy storage methods?

This is comparable efficiency to batteries but less expensive and with significant reuse of well-established technologies and industries (e.g. most of the construction work can be done by existing rail contractors).

Although battery technology continues to advance, my suspicion is that large-scale electricity storage is going to tend to be mechanical for cost reasons.

Very interesting though. I wonder how far those trains travel, and if there's some way to use them simultaneously as energy storage and transmission infrastructure. I guess it depends on how the energy is recaptured. I'm just wondering because that could solve some of the cost issues associated with putting big solar arrays out in the middle of the desert...

Something like a linear alternator maybe?

https://en.wikipedia.org/wiki/Linear_alternator

Love that they call it the ‘Sisyphus Railroad’.

https://en.wikipedia.org/wiki/Grid_energy_storage

I think it's an interesting field though.

http://www.inference.eng.cam.ac.uk/withouthotair/.

It's a "hard-headed" engineering look at our energy options written by a physicist. It might be a bit outdated (published in 2008), but when it came out it was the best compendium I'd seen.

http://www.inference.phy.cam.ac.uk/withouthotair/c6/page_41....

"If a breakthrough of solar technology occurs and the cost of photovoltaics came down enough that we could deploy panels all over the countryside, what is the maximum conceivable production? Well, if we covered 5% of the UK with 10%-efficient panels, we’d have 10% × 100 W/m^2 × 200 m^2 per person ≈ 50 kWh/day/person.

I assumed only 10%-efficient panels, by the way, because I imagine that solar panels would be mass-produced on such a scale only if they were very cheap, and it’s the lower efficiency panels that will get cheap first."

This assumption was invalidated by the actual trajectory of solar power since 2008. Nobody is building solar farms with 10% efficiency panels any more. Low efficiency is too expensive -- because it requires more glass and aluminum for the panels, more cabling, racking, and labor for installation. Low cost, low efficiency Chinese panels, like the GCL Poly ones used at India's giant new solar farm that HN just had an article about, are now in the mid-teens. (I looked up the data sheet after getting a glimpse of the GCL shipping crates on that Indian project site):

http://www.solarpanelsplus.com/PV-Specials/GCL%20245.pdf

If they used the middle-of-the-road GCL‐P6‐60‐240 that's a 14.7% module; 47% better than MacKay estimated as the best one could hope for from large scale solar projects. And the minimum competitive efficiency for even low-price panels is still creeping up. (Though large scale storage sufficiently affordable to get UK energy primarily from PV is still but a dream.)

MacKay also made the challenge look even bigger than it is by estimating the energy consumption of a "typical moderately-affluent person" and then multiplying that value by the whole population of the UK: http://www.inference.phy.cam.ac.uk/withouthotair/c2/page_22....

This leads to large over-estimates relative to actual measured UK energy consumption, particularly from air travel and automobile travel.

> MacKay also made the challenge look even bigger than it is by estimating the energy consumption of a "typical moderately-affluent person" and then multiplying that value by the whole population of the UK (...)

Here I'd agree with him: we need to find energy sources that will deal with projected future demands.

http://www.tsp-data-portal.org/Energy-Consumption-per-Capita...

You might think that's just because the UK doesn't do manufacturing any more, but look at manufacturing powerhouses Japan and Germany: they also have seen per-capita declines since 2008.

Ecologists and economists alike seem to have a default assumption that human resource consumption is insatiable; they just have different attitudes about that assumption. I don't know how many years of trends like the one I just linked it will take before they reassess resource satiety.

EDIT: here we go - http://www.nature.com/articles/srep04315 . Lithium iron phosphate batteries (LiFePO).

Although I'm assuming this particular combination doesn't provide favourable enough economics (or it would probably be a household name already), I can definitely see how this approach in general could. You could have the best of both worlds: cheap, but slow charge/discharge storage combined with the ability to very quickly scale up to meet peak daily demand for a limited (but sufficient) period of time.

But temperature differential storage, pressure differential storage, and creating hydrogen all seems to scale better to me.

I'm surprised that hydro could be considered safer than nuclear. That seems incorrect based on past experience.

Hydro dam failures have caused hundreds of thousands of deaths during the past 50 years or so. That's far more than Chernobyl and other nuclear disasters, even accounting for later deaths due to radiation-related diseases.

The Banqiao Dam failure alone in 1973 killed 171,000 and displaced more than 11 million people.

First and foremost, it was an administration, planning and design failure, compounded by weather, enineering, response, and other factors.

The background was adminstrative pride, ignored engineering warnings, insufficient spillways, poor communications, and no disaster planning.

The immediate trigger was an unprecedented "perfect storm" -- the collision of a tropical typhoon and a cold front -- unleashing 1,000+ mm of rain in 24 hours, completely overwhelming the dam.

The area was densely populated, what communications there were were down on account of the storm, and rougly 20,000 people were killed in the immediate flooding. The remaining 100,000 deaths occurred due to disease and starvation in the area as a result of no effective disaster and recovery response.

The most telling characteristics of Banqiao though are these:

1. Some 40 years after the incident, the region is not a nondiscretionary multi-centennary wildlife preserve and exclusion zone, but home to some 17 million inhabitants. That is, once a flood zone stops being a flood zone, it returns to its previous state relatively quickly.

2. Banqiao itself is far and away the most extreme accident of its type. There have been other major dam-related incidents, in India and Italy (Vajont Dam tsunami), but each was some two orders of magnitude lower in deaths than Banqiao.

The common elements in virtually all dam disasters are 1) poor understanding of risks, 2) suppression of criticisms, and 3) poor or no warning systems.

Keep in mind that dams are simple systems from an engineering standpoint: a large mass of material which regulates water flows. And yet these do fail with some regularity most especially in less-developed areas. The premise that the complexity of nuclear power plants will somehow pose fewer risks lacks credibility.

https://en.m.wikipedia.org/wiki/Banqiao_Dam

https://www.internationalrivers.org/resources/the-forgotten-...

Regarding storage and distribution the video reports on a current project in Utrecht/Netherlands where they are combining the untapped storage capacity of electrical cars. As a Tesla owner you can set the amount of milage you will need the next day and the rest of the capacity can/will be used for storage and distribution.

Imagine that, if demand is high and your Tesla is charged you can take the bike and sell the electricity for profit. So the Tesla might pay for itself over time.

Regarding potential over capacity by solar generation I think the electric car revolition is just about to start. There will be huge demand for electricity in the near future.

On the contrary to the costs of storage and distribution, which are often cited and remarked upon in discussions about renewables, the cost of enviromental damage is also not included in the power generation costs. If you factor in the value of the land that became virtually unusable by fukushima, I guess the power generation costs will unlikely be as low as the are presented to be. I vaguely remember figures from someone who did the math for nuclear, this person also subtracted the nuclear industry subsidies, and I think it was 69$/kWh. Yes, sixty nine dollars per kilowatt hour. I wish I had saved that reference. I can not vouch or this value, it is only from the back of my head.

In a worst case scenario, if we go full solar, but are unable to slow a climat change that induce more cloudy weather (because more global evaporation) we are actually solving nothing.

Nuclear have a lots of cons, but the one of the pro is that we know them, while renewables are mostly untested at scale that approach current global electricity demand. (PS: Indeed lowering electric need is also a safe way to to reach the goal and should be the top priority)

In the worst case scenario, all of the nuclear reactors simultaneously explode (because more earthquakes), raining down a radioactive armageddon on the hordes of screaming peasants below.

Worst case scenario is that it gets more cloudy and our solar doesn't work as well. But lets not forget solar power still works on a cloudy day, just not as well

2013 world electrical energy generation was 23,322 TWh, with 41.3% being coal (so, 9,632TWh from coal). Presumably consumption was somewhat less (overproduction, transmission losses etc.), but let's just use this figure as it's probably grown anyway in the last few years. So:

(a) Coal generation in MWh: 9,632 * 1,000,000 = 9,632,000,000MWh

(b) 1 AP-1000 running full-time: (365 * 24) * 1,117MWe = 9,784,920MWh

Number of AP-1000s needed to replace all coal plants = (a) / (b)

Total plants to replace coal = 984.4

That seems absurdly small, so I assume I've gotten a unit conversion wrong. Any engineers able to help me out here?

EDIT: If 984.4 is indeed correct, if an AP-1000 costs $7bn to build on average (using the expected cost of the two US Vogtle plants), this works out to $6.89 trillion. That doesn't seem too bad, particularly given US safety standards appear to be a fair bit better than the world average...

On the other hand, I would expect repeated installation of the same AP-1000 model to reduce in cost over time, so that will help out a bit - although R&D into more interesting plant designs may bring prices up as well.

For some reason people are still scared of radiation even after seeing how harmless Chernobyl turned out to be compared to predictions.

except for the people that literally had to give up their lives in order to save the situation and not let it grow many times worse. knowing they were stepping into the radiation that would kill them in a few hours (if they were lucky).

hey if it's not very deadly, why don't you volunteer for being one of those heroes the next disaster

also Fukushima is not yet done doing damage, not by a long shot.

let's evaluate the "once every 30 years is no biggie, really" thing once we spent 30 years trying to clean it up.

> how harmless Chernobyl turned out to be

because all those malformed children being born must've been a hoax, or something.

btw I wasn't against nuclear energy at all (except by now it's kinda too late really, and once we realize the next plan B will be too late, but at least we'll keep on making new humans to witness the carnage) but it was because I thought we could actually do better than Chernobyl and Fukushima, not to take it as a calculated risk. That is horrible. I'd easily give up "air-conditioning and data centres" to prevent that shit (easy to say, I don't have AC, and data ... well we could really do with a little bit less of those, take a moment and think about what is stored in those because it's so ridiculously cheap, at best it's worthless data).

I know we've passed the 400ppm threshold, it's too late to prevent that, but its not "too late" to switch the planet to renewable energy. It can never be too late for that. We can't stop the catastrophic effects of climate change that we'll likely see in our lifetimes, but we can hopefully stop it from being even worse

http://m.nautil.us/issue/25/water/the-hidden-importance-of-c...

Increasing of earthquake on the other hand is a far as I know a scenario you just made up, but feel free to elaborate.

What might happen in disaster situations is the backup generators that power the cooling systems explode. But that wouldn't cause radioactive material to rain down either since these generators would be running off a petroleum (or similar) fuel.

Renewables being tested at scale isn't really a concern. There are now multiple cases of islands being 100% renewable, with energy storage in the form of pumped hydro, or as is becoming increasingly common, lithium-ion battery storage. I live on a college campus that's in the middle of a massive wind-farm, and is almost entirely renewable most days. And this isn't some small wind-farm; it has a peak output of over a GW.

Scale, isn't the problem with renewables - it's storage. However, with the current cost reductions that we're seeing with batteries, I think it'll be a solved conundrum within the decade. It won't be too long before solar with batteries is cost-competitive, as both technologies are getting cheaper exponentially.

https://en.m.wikipedia.org/wiki/Onkalo_spent_nuclear_fuel_re...