A near 100% renewables grid is well within reach, and with little storage • Hacker News Board

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

#121

Post by pydry » Wed, Aug 24, 2022, 6:07 PM UTC

jnsaff2 wrote: post #86

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.

PV can be throttled instantly to anything down to 0. Otherwise no offgrid setup would be feasible. You can mandate smart control signals to PV inverters or don't do anything and let the frequency go up so even inverters installed today will start cutting power as this is a requirement from grid code. Wind has a bigger lag (seconds) but it has brakes to save them in storms. So those are easy problems (technologically)…

It's better to use price signals to ratchet demand up if you can.

The UK already has a tariff that can warn you about upcoming periods of free power. Electric car users like it. They like it a lot.

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

#122

Post by onlyrealcuzzo » Wed, Aug 24, 2022, 6:08 PM UTC

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…

I made the comment because I'm from California, and I don't think brown outs are catastrophic, and I think 99% renewable energy would be fine (better than fine? definitely not catastrophic).

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

#123

Post by WalterBright » Wed, Aug 24, 2022, 6:08 PM UTC

theluketaylor wrote: post #31

wyager wrote: post #29

Earlier quoted context omitted.

Transmission losses would eat any benefit, unfortunately. Of course, the author didn't model this at all. This is the problem with 99% of "actually we could totally rip out our entire infrastructure right now" posts - it's usually justified with crappy modeling that falls apart under slightly more scrutinizing consideration. Solar-only with low storage overhead might become more viable if we get room-temperature supe…

Losses wouldn’t be bad with HVDC, with the added benefit of HVDC ties not needing to be frequency synced across the entire grid, so you have some opportunity to increase resiliency. I don’t think it’s a one-sized fits all solution. There will be places where storage will make sense, and other where longer distance transmission makes sense. I think the reality is it will be a mix of both, along with a nice diverse mix…

> Losses wouldn’t be bad with HVDC

Uh-oh. We're going to have to rewrite the history books on the current war between Edison and Tesla, this time with Edison as the victor!

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

#124

Post by galangalalgol » Wed, Aug 24, 2022, 6:10 PM UTC

ZeroGravitas wrote: post #99

anonporridge wrote: post #96

Earlier quoted context omitted.

Is California at the point now where more renewables are not just diminishing returns, but potentially negative returns due to inconsistent generation causing thrashing and large levels of curtailment required to stabilize the grid? They're definitely causing faster natural gas generator breakdown due to them having turning up and down more frequently, causing greater wear and tear. More batteries and demand response…

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 hottest summer.

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

#125

Post by thrown_22 » Wed, Aug 24, 2022, 6:11 PM UTC

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.

Australian energy prices doubled in the last 6 months.

I'm not sure who would ever use the Australian market as a model, other than "under no circumstances follow suit".

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

#126

Post by Schroedingersat » Wed, Aug 24, 2022, 6:12 PM UTC

evancox100 wrote: post #110

Schroedingersat wrote: post #103

Earlier quoted context omitted.

For the cost of 5kW nameplate of new western nuclear (>$10/W) you can get, right now, at retail, as an individual: 50kW nameplate of solar, and 8kW nameplate of wind, and 75kWh of storage and a 5kW generator (which will almost never need turning on) and a biogas digester. And it will produce enough excess power to replace itself (with a cheaper version) or just triple the batteries if you can get 2-3c/kWh for the sur…

So you can buffer the wind/solar output for just 78 minutes? Doesn’t sound like a complete solution. Edit: I guess per the paper it really depends on the specific details of generation/load timing. Could be workable for a certain region but not for another.

The demonstration is 5kW year round with insignificant consumption of fossil fuels everywhere with a climate about as good as Toronto or better, not having somewhere to put all the sunlight. Mid-winter in high latitude you get as little as 2hrs of sunlight/day (or 0 in the arctic, but hardly anyone lives there). If you live in the tropics, 10kW is probably fine.

Also if you feel the need to use it up, electrolyzers are cheap and hydrogen is worth money. You can also store a great deal of energy in a few tonnes of NaOH and avoid using precious winter electricity for heating.

You can also reshuffle the wind, solar and battery for your local climate, or wait a year or three for sodium batteries to halve the price.

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

#127

Post by throwaway894345 » Wed, Aug 24, 2022, 6:13 PM UTC

ZeroGravitas wrote: post #69

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.

Quite a lot of people live in Texas and California where renewables are already pretty advanced, plus there's nuclear in the north, and they have hydro and grid connections with Canada who have even more hydro and nuclear so the USA should be easier. The US intends to hit this target (i.e. 95% carbon-free generation) in 8 years I think, with 100% and wider electrification of current fossil fuel uses in 2035 and it di…

The problem is that electrification of fossil fuel applications is going to significantly increase the demand on our grid. So it’s not enough to get to parity in renewables, but we have to go far beyond our current capacity in order to accommodate a world in which almost every car is electric (whether electric hybrid or green hydrogen) and almost every home uses electric rather than natural gas for heating (not to mention all of the industrial applications that will need electrification).

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

#128

Post by ciconia » Wed, Aug 24, 2022, 6:13 PM UTC

A few random thoughts:

1. There are symbiotic relationships between different sources of energy. In order to suck petrol out of the earth we need coal (used in steel manufacturing). In order to mine coal we need petrol (used by diggers and for transport). We still don't know how to manufacture solar panels and wind turbines without fossil fuels. The mining, steel forging and international transport of these products is still based on fossil fuels.

2. Electricity consumption represents only about 30% of total energy consumption. A lot of people seem to underestimate the difference in energy density between petrol and lithium batteries. This difference makes it highly unlikely that we'll move to electric ships and aircraft in the near future.

3. The mining activity associated with manufacturing solar panels, wind turbines, batteries, smartphones and electric cars is highly demanding in energy, is highly polluting, and demands great quantities of fresh water as part of the process of refining the different metals. With the rise of electric cars, the continuing demand for smartphones mining is expected to demand even more energy and fresh water, and pollute even more our rivers and soils. This, in a period of constrained energy sources, droughts, and an already degraded environment.

4. Judging by the comments on here people demand an always-on supply of energy, be it electricity, petrol or gas, which is a privilege only some countries enjoy today, and is relatively recent in human history. I think the idea of intermittent energy supply is worth exploring, and might make it easier to achieve 100% renewable energy production, in conjunction with a lower energy consumption.

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

#129

Post by pydry » Wed, Aug 24, 2022, 6:15 PM UTC

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.

That was literally everybody's plan. The alternative was to continue using coal while ramping up renewables.

For all the handwringing about the turned off nuclear plants they were getting old in the tooth and wouldnt have made a substantive difference to the current crisis. New plants would take 3x as long and cost 3x as much.

France is in just as much shit as germany this winter coz their nuke plants are aging out.

The realistic alternatives for germany avoiding a gas crisis were dont turn off coal plants "just in case a war with russia starts" or dont try to rile up russia.

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

#130

Post by anonporridge » Wed, Aug 24, 2022, 6:16 PM UTC

ZeroGravitas wrote: post #99

anonporridge wrote: post #96

Earlier quoted context omitted.

Is California at the point now where more renewables are not just diminishing returns, but potentially negative returns due to inconsistent generation causing thrashing and large levels of curtailment required to stabilize the grid? They're definitely causing faster natural gas generator breakdown due to them having turning up and down more frequently, causing greater wear and tear. More batteries and demand response…

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.

It's not a technical issue, but an economic one.

If you have so much wind and solar generation that they spend too much of their lifespans sitting idle and not generating income, they potentially never even pay for their initial build cost and basic maintenance, let alone be a better investment than just buying a treasury note yielding 1%. That's a recipe for long term stagnation and depression.