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A near 100% renewables grid is well within reach, and with little storage

reneweconomy.com.au

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Re: A near 100% renewables grid is well within reach, and with little storage

#241

Post by mactitan »

ParksNet wrote: post #169

Its unclear if we even have the metal mining capacity (or the ores in the ground) to do this: https://www.youtube.com/watch?v=MBVmnKuBocc

A very compelling case and the material for 100% renewables is staggering. How this can be ignored is bewildering.

A discussion at:

https://www.reddit.com/r/collapse/comments/wuc4vg/assoc_prof...

Simon Michaux presents the deck of data showing details of where his calculations are coming from that show even the first generation of renewables to replace fossil fuels is going to outstrip our capacity to source the minerals (lithium, copper, vanadium, manganese, cobalt, etc required for only the first generation of renewable energy) and the amount of energy to be replaced based on efficiencies is exorbitant. Summary: EROI going down, mineral requirements going way up spell issues moving forward.

Re: A near 100% renewables grid is well within reach, and with little storage

#242

Post by pfdietz »

thayne wrote: post #57

"in Australia" is an important qualification here. Australia has a very high ratio of available solar and wind energy to population. Not that getting Australia fully on renewables wouldn't be exciting. But it is definitely an easier target than say the US.

It's not significantly easier than the US, which also has an embarrassingly large surplus of land for solar and wind.

Re: A near 100% renewables grid is well within reach, and with little storage

#243

Post by pfdietz »

s1artibartfast wrote: post #214
theluketaylor wrote: post #180

Earlier quoted context omitted.

If whole solar or wind farms find themselves sitting idle someone will drop off some containers nearby to split water into hydrogen or run a data center or something else that drinks power and skip the grid middle-man. Over-idle is not going to be a real issue; someone will always find a way to use of excess power.

Over idle already is a real issue. Who is going to build a hydrogen generator or data center with a 80% idle time, operating only 12-4 PM?

Another use is thermal batteries. Dump the power into a resistively heated mass and use that for industrial purposes. Thermal storage can be incredibly cheap per stored unit of energy.

Re: A near 100% renewables grid is well within reach, and with little storage

#244

Post by pfdietz »

galangalalgol wrote: post #124
ZeroGravitas wrote: post #99

Earlier quoted context omitted.

No, because there never is such an issue. Renewables can turn themselves off and on so fast that this won't ever be a problem. The current Australian model we're discussing has about 15% 'overgeneration' because that's economically efficient, there's no problems caused by that.

Can you build out enough capacity that the lowest wind conditions during nighttime in winter don't cause outages? I worry about distribution as the answer due to the vulnerability of our existing power distribution infrastructure. Do we have answers for that yet? We need them in any case I suppose unless you build out local storage to such an extent that you don't need any grid at all even in the coldest winter or ho…

You can back up the entire grid with combustion turbines burning hydrogen or some other e-fuel. A simple cycle combustion turbine power plant costs $500/kW, 20x cheaper than a nuclear plant ($10,000/kW).

Re: A near 100% renewables grid is well within reach, and with little storage

#245

Post by ars »

themitigating wrote: post #72
itsoktocry wrote: post #61

Earlier quoted context omitted.

> Ah yes, let's point the finger at California and ignore the one state... Wow, this comment is so indicative of modern discourse. The parent makes an off-hand reference about a state where brown outs have been an issue, (Democratic) California, and you feel the need to jump in with "WHY ARE YOU IGNORING (Repulican) Texas???" as if there's some political motivation behind an innocuous statement of fact.

Why did the parent make the off hand reference? Republicans know if they keep repeating such remarks (or accusations) it will eventually will just be accepted as fact without requiring evidence because people hear it from so many different people over long periods of time. They don't lie either, they just bring to attention a problem in a blue state or with a company considered to be liberal" and ignore similar issue…

Out here in the real world California has far more power problems than Texas.

And yeah, it's basically because foolish environmentalist forced the closure of a number of nuclear plants in California.

Re: A near 100% renewables grid is well within reach, and with little storage

#246

Post by pfdietz »

megaman821 wrote: post #175
eldaisfish wrote: post #117

Earlier quoted context omitted.

What you have in mind requires someone to do the coordination. that is currently the system operator and they operate at a data rate measured in minutes or 4 s for the fastest changes (e.g. PJM). Meanwhile, solar output can go from 100% to 10% in three seconds. How is this not a problem?

Well, you need a 30 minute battery buffer to get gas peakers online. Whether those gas peakers are running natural gas or green hydrogen depends on how much excess solar capacity there is and how much hydrogen plants cost. Also, medium term storage is a very, very young industry. Things like redox batteries, flow batteries, molten salt, compressed air, and many others are on the horizon. The better these work the mor…

Thermal storage, like resistively heated sand, can also act as a backup source, since once the sand is exhausted they could then resort to burning something to get the heat.

Re: A near 100% renewables grid is well within reach, and with little storage

#247

Post by s1artibartfast »

pfdietz wrote: post #243
s1artibartfast wrote: post #214

Earlier quoted context omitted.

Over idle already is a real issue. Who is going to build a hydrogen generator or data center with a 80% idle time, operating only 12-4 PM?

Another use is thermal batteries. Dump the power into a resistively heated mass and use that for industrial purposes. Thermal storage can be incredibly cheap per stored unit of energy.

I agree that there are solutions, I just think it is silly when people propose these high capital solutions. E.g. run a desalination plant 4 hours a day, ect.

The real solution, like you mention, is more capacity + storage. Pumped storage is my personal favorite, as it is much cheaper than batteries for anything more than 2 hours of power/day. Pumped seawater has a pretty small footprint.

Re: A near 100% renewables grid is well within reach, and with little storage

#248

Post by pfdietz »

cma wrote: post #83
cbhl wrote: post #70

Do we actually have effective strategies for dealing with significant over-generation? The author glosses over it as being necessary to get to 98% renewables throughout the year ("we'll just run our hydro dams in reverse"), but I'm under the impression that over-generation that is unhandled leads to grid instability/desync.

Maybe folding@home; desalination for farming; pumping and spraying water to re-glaciate areas in the winter.

Resistively heated thermal storage for any industrial plant that uses process heat.

Re: A near 100% renewables grid is well within reach, and with little storage

#249

Post by dont__panic »

theluketaylor wrote: post #204
dont__panic wrote: post #104

Earlier quoted context omitted.

Wow, that's a lot of hydro and nuclear power! Thanks for sharing. I wonder how the New England and upstate NY power grids compare, since they also have a lot of hydro and nuclear?

New England and upstate NY don't generate nearly enough power for their own needs and buy excess power from Ontario and Quebec. Quebec in particular as Hydro Quebec has a terrifying amount of hydro generation and always has tons of excess. A big chunk of the clean energy in the northeast US comes from Canada. Super cool tool that shows the CO2 intensity of various grids and where power is flowing: https://app.electri…

Very cool site, thanks for linking. Does most of Quebec's hydro power come from dams on the St. Lawrence river? (this would make sense to me, considering the St. Lawrence is the outlet for the largest reservoir of fresh water in the entire world) Or is there another source I'm not thinking of?

Re: A near 100% renewables grid is well within reach, and with little storage

#250

Post by pfdietz »

skrause wrote: post #84
colechristensen wrote: post #73

If you lower this to, say, 75%, a good analysis will show that a renewables grid with zero storage is possible around the world. Storage is only required for the last n % and n is much larger than most people realize. If we accept that the energy economy will shift with supply-and-demand based pricing, what can actually happen is having peak production oversupply which will find users with its lower prices enabling o…

That was Germany's plan. Go to at least 80% renewable and fill up the rest with natural gas power plants that can change the load quickly. Oops.

They could use hydrogen instead of natural gas. Today, green hydrogen in Europe would be cheaper per BTU than natural gas.
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