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

reneweconomy.com.au

111–120 of 365 posts

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

#111

Earlier quoted context omitted.

The "Victorian Big Battery" cost about 100 million to build and provides 450MWh, so at those prices the 120GWh they calculate for 5 hours would cost about 25 billion. Not outrageous in the scale of nation building projects.

They won't use batteries for grid scale storage, that's a bit too expensive. They'll probably use hydro, some sort of heated mass or compressed air. Or gas, it's much better than coal at least.

I think Australia will use mostly batteries, but we are building more hydro. I think hydro is miscast as being green though, when in reality it causes enormous ecological destruction.

Hydro is also intermittent - it requires the right amount of rainfall, currently hydro in Australia is not able to reach full generation because it will flood downstream as it's been a wet year.

Hydro is not that cheap (depending on the metric you need) - see an example[1] comparing Australian hydro to the aforementioned Victorian Big Battery.

[1] https://www.solarquotes.com.au/blog/snowy-2-vs-battery-stora...

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

#112
post #10

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.

> 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.

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

#113
post #82

Earlier quoted context omitted.

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…

> even before the recent climate bill passed What is in the bill that is investment in renewables? My understanding is that there aren’t so much subsidies to generators-suppliers, but rather rebates and savings for homeowners and consumers.

This podcast goes in depth on what's in the bill: https://www.youtube.com/watch?v=ZrfRbr_xbOE

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

#114
post #82

Earlier quoted context omitted.

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…

> even before the recent climate bill passed What is in the bill that is investment in renewables? My understanding is that there aren’t so much subsidies to generators-suppliers, but rather rebates and savings for homeowners and consumers.

Getting people to use more efficient appliances and insulating their homes should help reach these targets. We don't need to generate today levels of energy if we can drop usage by some percentage and just generate all of that with renewables.

That being said, the bill is also pushing for heat pumps to replace natural gas burning furnaces, so I'm guessing the net impact will be we need today levels of electricity generation, or maybe even a little more once we look at electrifying things that currently don't interact with the grid and consume fossil fuels directly.

And actually as I even type this, I'm remembering that electrifying cars is a big part of this that will definitely drive up electricity need way more than efficiency gains suppress demands for some use. Hopefully we can get to some of the more transformative ideas suggested about improving city planning and density together with investments in public transit so we don't end up producing way too many batteries simply to preserve a car centric transportation system.

I do think even just incentivizing consumers to buy electric everything will have a strong movement to drive more electricity generation, and renewables are the cheapest or very cost competitive options for new power generation installations. I think there are some funds in the new bill for encouraging sunsetting fossil fuel based plants early, but we likely need more of that down the line.

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

#115

Earlier quoted context omitted.

62% of the power in Oregon comes from renewables, mostly renewables that are available 24/7.

Yeah, but that renewable hydro is unlikely to grow much in the USA, while wind and solar will be growing exponentially. Hydro is cool, and works well with solar/wind/nuclear to help match supply and demand, but ... If you look at global renewable output, the big chunk of hydro production that's been flat for decades, somewhat obscures the recent sudden rise of solar and wind.

Swapping hydro from 24/7 power to a backup for wind and solar goes a long way to eliminate the need for storage. We don’t need more total kWh per year of hydro we need to be able to more flexibility get those kWh.

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

#116

Earlier quoted context omitted.

Cloud doesn't mean solar stops working - the decrease is 30-60% depending on thickness, but there's still very meaningful generation.

We get about nine and a half hours of sun in January, assuming no clouds. That leaves around 14-15 hours of no production, assuming there isn't sufficient wind (also often the case in January). Panels operating at 30% capacity for 9 hours cannot be offset by 5 hours worth of storage. It simply isn't enough storage, even if the panels were operating at 100% capacity. Adding more storage really isn't a great solution e…

You can also over-provision solar and wind to factors well above 100%, and still be more economical than burning fossil fuels.

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

#117

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.

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?

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

#118

Earlier quoted context omitted.

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…

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…

nuclear definitely needs to be in the mix to reach 100% fossil-fuel-free energy generation; not gonna happen on wind/solar/hydro alone

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

#119
post #34

Earlier quoted context omitted.

Quoted post unavailable.

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 hav…

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.

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

#120

Earlier quoted context omitted.

Cloud doesn't mean solar stops working - the decrease is 30-60% depending on thickness, but there's still very meaningful generation.

it also creates another problem - solar generation drop off very quickly when the sun is obscured. going from 100% to 10% or 20% in many cases. Where doe the power come from during these swings? What generation source can ramp up and down at that speed?

Synchronous condensers or smart batteries. Australia has deployed a lot of the former to deal with this problem at solar farms.
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