5 ms·

The averages don’t tell me much. We need to look at percentiles with intermittent sources of energy. 99% still means 3 full days of blackout every year. So it n

by cm2187 4y ago

The averages don’t tell me much. We need to look at percentiles with intermittent sources of energy. 99% still means 3 full days of blackout every year. So it needs to be sufficient to cover an even higher percentile (in fact I don’t even think there is an acceptable number of hours of blackout in a year). I would be curious how they get to that with energies that pretty much go to zero the week there is no wind.

toomuchtodo 4y ago
Fossil gas short term, green ammonia long term. With enormous amounts of clean energy and air source carbon capture, you can carbon budget for last resort combustion generation. You might have to burn something to keep the lights on, you’re just on the hook to pay Climeworks or someone else to pull that carbon back out of the atmosphere (which will be done with clean energy) and that cost is built in the per MWh spot price. https://royalsociety.org/topics-policy/projects/low-carbon-energy-programme/green-ammonia/ https://royalsociety.org/topics-policy/projects/low-carbon-e...
philipkglass 4y ago
That's what is different about this new study. It uses real time supply/demand figures instead of annualized averages. It meets 98.8% of demand with renewables and fills in with fossil power the rest of the time. To quote from the article: Key results from the 52 weeks of simulations are summarised as follows: - Renewables met 98.8% of demand over the year, with the remaining 1.2% met by ‘Other’ (fossils) - ‘Other’ generation peaked at 6.59 GW on the night of July 12. Over the year its average capacity factor was 4.3%. - Hydro met 6.9% of demand. This was lower than my target of 7.5%, and also less than actual hydro generation of 8%. This means that dam storage levels in my simulation would have ended the year higher than they did in the real world. - 17% of the wind and solar generation was in excess of requirements and ended up being curtailed. - 11% of wind and solar generation went into storage. Storage discharge met 10% of demand. - 82% of demand was directly powered by wind and solar without having to pass through storage or be curtailed.
- atoav 4y ago
  > 82% of demand was directly powered by wind and solar without having to pass through storage or be curtailed. This is amazing. As an EE I wonder about transportation losses, but wind and solar should be pretty easy to decentralize, so maybe this is a non-issue. Wind might be a little harder to decentralize, but I don't know how the regional differences are in Australia. I'd suspect the coasts (or even offshore) would be windiest, which is also where most people tend to live.
  - syncsynchalt 4y ago
    Solar can be decentralized, wind less so. I don't know what wind looks like in Australia but in the US it heavily favors places like the Front Range and the Wyoming Divide: https://california-times-brightspot.s3.amazonaws.com/77/87/86477844441ca7e3f84fdd6af9fd/wind420-4x-update.png https://california-times-brightspot.s3.amazonaws.com/77/87/8... EDIT: Looking at the same map for Australia I see that wind power potential tends to be strongest coastally, which matches population density (nice!) I'll still say that overall you can't expect to decentralize wind like you can with solar.
    - mattferderer 4y ago
      That map doesn't take off shore into an account though. Lots of potential in the oceans & Great Lakes.
      - zo1 4y ago
        Am I the only one that's kinda off put or frankly disgusted by the thought of ruining our nature by peppering it with giant wind turbines? At what point does it stop?
        cheriot 4y ago
        What do you think drilling rigs, pipeline leaks, and carbon emissions are doing right now? The impact on nature by renewables is dramatically lower. But your comment focuses on what's visible so no, I'm not put off by that. Wind turbines look cool.
onlyrealcuzzo 4y ago
> 99% still means 3 full days of blackout every year. Presumably the entire grid isn't going down. Brown outs in small parts of the country is what I'd expect. This sounds like the current state of California.
- malfist 4y ago
  - nonameiguess 4y ago
    Honestly, it's gotten better in the last few years, but when I first moved to Dallas, the most noteworthy thing wasn't even these high-profile large-scale outages. It was the poor state of infrastructure in general. Above-ground power lines combined with trees the city never trimmed meant we had outages from lines going down virtually every time there was a rain storm. Really, that still happens, but they seem to have finally built enough redundancy in that it comes right back, instead of coming back hours later like it used to.
    - evancox100 4y ago
      Omg for real, moved out of Dallas a few years ago but every moderately strong storm we would lose power. Totally ridiculous. They came and trimmed trees one time, and absolutely decimated a small tree on my property that had one branch close to the line, while leaving alone huge trees that were completely intertwined with the lines.
  - itsoktocry 4y ago
    >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.
    - 4y ago
ebiester 4y ago
Or, alternatively, a handful of gas plants working at this load like peaking power plants work now. So, for 72 hours or so, where the full need isn't met, we have some very expensive alternatives. According to wikipedia, some peaker plants may work as little as a few hours a year. Or, we have a set of solar thermal energy power plants that can function as peakers down the road.
ZeroGravitas 4y ago
This isn't an average it's modelled on real-time demand and supply and the 99% means 3 days worth of power met by non-solar/wind/hydro peaker plants over a year, not instantly plunging into a 3 day long version of Mad Max.
pydry 4y ago
>99% still means 3 full days of blackout every year. Or using some excess wind capacity to generate some windgas at and keeping it stored using existing natgas infrastructure. The windgas process is only 50% efficient at converting electricity so it's only cost effective if it's used for say, <1% of electrical needs. These calculations also dont take into account demand shaping. If you can convince people to stop smelting aluminium so much and charging their cars on the off day that reduces storage needs still further.
ajross 4y ago
> 99% still means 3 full days of blackout every year. Or 3 days running otherwise-mothballed (and, yes, quite expensive per MW) gas plants or whatever to fill the gaps. There's a real problem in this discourse that wants to interpret things in absolutist ideas, when real solutions always end up looking a little patchwork in those last few percent. Reducing electrical grid carbon output by a factor of 100 (!!) is more than sufficient to meet anyone's climate goals. At that point, the low-hanging-fruit analysis will have long since moved on to transportation anyway.

by cm2187 4y ago

toomuchtodo 4y ago

Fossil gas short term, green ammonia long term. With enormous amounts of clean energy and air source carbon capture, you can carbon budget for last resort combustion generation. You might have to burn something to keep the lights on, you’re just on the hook to pay Climeworks or someone else to pull that carbon back out of the atmosphere (which will be done with clean energy) and that cost is built in the per MWh spot price. https://royalsociety.org/topics-policy/projects/low-carbon-energy-programme/green-ammonia/ https://royalsociety.org/topics-policy/projects/low-carbon-e...

philipkglass 4y ago

That's what is different about this new study. It uses real time supply/demand figures instead of annualized averages. It meets 98.8% of demand with renewables and fills in with fossil power the rest of the time. To quote from the article: Key results from the 52 weeks of simulations are summarised as follows: - Renewables met 98.8% of demand over the year, with the remaining 1.2% met by ‘Other’ (fossils) - ‘Other’ generation peaked at 6.59 GW on the night of July 12. Over the year its average capacity factor was 4.3%. - Hydro met 6.9% of demand. This was lower than my target of 7.5%, and also less than actual hydro generation of 8%. This means that dam storage levels in my simulation would have ended the year higher than they did in the real world. - 17% of the wind and solar generation was in excess of requirements and ended up being curtailed. - 11% of wind and solar generation went into storage. Storage discharge met 10% of demand. - 82% of demand was directly powered by wind and solar without having to pass through storage or be curtailed.

atoav 4y ago
> 82% of demand was directly powered by wind and solar without having to pass through storage or be curtailed. This is amazing. As an EE I wonder about transportation losses, but wind and solar should be pretty easy to decentralize, so maybe this is a non-issue. Wind might be a little harder to decentralize, but I don't know how the regional differences are in Australia. I'd suspect the coasts (or even offshore) would be windiest, which is also where most people tend to live.
- syncsynchalt 4y ago
  Solar can be decentralized, wind less so. I don't know what wind looks like in Australia but in the US it heavily favors places like the Front Range and the Wyoming Divide: https://california-times-brightspot.s3.amazonaws.com/77/87/86477844441ca7e3f84fdd6af9fd/wind420-4x-update.png https://california-times-brightspot.s3.amazonaws.com/77/87/8... EDIT: Looking at the same map for Australia I see that wind power potential tends to be strongest coastally, which matches population density (nice!) I'll still say that overall you can't expect to decentralize wind like you can with solar.
  - mattferderer 4y ago
    That map doesn't take off shore into an account though. Lots of potential in the oceans & Great Lakes.
    - zo1 4y ago
      Am I the only one that's kinda off put or frankly disgusted by the thought of ruining our nature by peppering it with giant wind turbines? At what point does it stop?
      - cheriot 4y ago
        What do you think drilling rigs, pipeline leaks, and carbon emissions are doing right now? The impact on nature by renewables is dramatically lower. But your comment focuses on what's visible so no, I'm not put off by that. Wind turbines look cool.

onlyrealcuzzo 4y ago

> 99% still means 3 full days of blackout every year. Presumably the entire grid isn't going down. Brown outs in small parts of the country is what I'd expect. This sounds like the current state of California.

malfist 4y ago
- nonameiguess 4y ago
  Honestly, it's gotten better in the last few years, but when I first moved to Dallas, the most noteworthy thing wasn't even these high-profile large-scale outages. It was the poor state of infrastructure in general. Above-ground power lines combined with trees the city never trimmed meant we had outages from lines going down virtually every time there was a rain storm. Really, that still happens, but they seem to have finally built enough redundancy in that it comes right back, instead of coming back hours later like it used to.
  - evancox100 4y ago
    Omg for real, moved out of Dallas a few years ago but every moderately strong storm we would lose power. Totally ridiculous. They came and trimmed trees one time, and absolutely decimated a small tree on my property that had one branch close to the line, while leaving alone huge trees that were completely intertwined with the lines.
- itsoktocry 4y ago
  >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.
  - 4y ago

ebiester 4y ago

Or, alternatively, a handful of gas plants working at this load like peaking power plants work now. So, for 72 hours or so, where the full need isn't met, we have some very expensive alternatives. According to wikipedia, some peaker plants may work as little as a few hours a year. Or, we have a set of solar thermal energy power plants that can function as peakers down the road.

ZeroGravitas 4y ago

This isn't an average it's modelled on real-time demand and supply and the 99% means 3 days worth of power met by non-solar/wind/hydro peaker plants over a year, not instantly plunging into a 3 day long version of Mad Max.

pydry 4y ago

>99% still means 3 full days of blackout every year. Or using some excess wind capacity to generate some windgas at and keeping it stored using existing natgas infrastructure. The windgas process is only 50% efficient at converting electricity so it's only cost effective if it's used for say, <1% of electrical needs. These calculations also dont take into account demand shaping. If you can convince people to stop smelting aluminium so much and charging their cars on the off day that reduces storage needs still further.

ajross 4y ago

> 99% still means 3 full days of blackout every year. Or 3 days running otherwise-mothballed (and, yes, quite expensive per MW) gas plants or whatever to fill the gaps. There's a real problem in this discourse that wants to interpret things in absolutist ideas, when real solutions always end up looking a little patchwork in those last few percent. Reducing electrical grid carbon output by a factor of 100 (!!) is more than sufficient to meet anyone's climate goals. At that point, the low-hanging-fruit analysis will have long since moved on to transportation anyway.