this post was submitted on 25 Sep 2024
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But where do we store the energy is the question. Without storage renewables aren't that useful.
I work in the UK energy sector, and that's definitely not true! About 1/3 of our energy comes from wind which is somewhat but mostly not stored.
Fossil fuels end up doing the work of balancing the grid during times when wind and solar are low. That's not ideal, but a world where fossil fuels are used to balance renewable provision is much better than a world where they're the primary energy source.
We're running out of time to prevent the worst effects of global warming, and any increase in renewables provides some mitigation to the impact. Very few, if any, countries are at the point where current battery tech should stop them increasing their renewables.
That's true, but only as long as your primary source/balancing source are fossil fuels. I can imagine a lot of them being burned during short and cloudy winter days + all nights in this scenario. If we want to avoid CO2 emissions, nuclear pps seems like the best choice today. But then we don't need nearly as much renewables. Tricky situation, even worse for countries without much wind.
Yep, because you are still relaying on fossil fuels and can adjust their output quite dynamically. But the more renewables power you have, the more fossil fuels you'll burn when renewables aren't producing.
Makes sense?
I agree with all of what you said, apart from "without storage renewables aren't that useful".
UK and USA are good comparatives here, where the USA has better nuclear provision, but on average very little renewables (approx 10%). The UK obviously burns more fossil fuels when renewables aren't used, but in spite of this still generates less than 1/3 of the co2 per KW overall as the USA (120g vs 390g).
So storage would be drive that down much further, but even without it, more renewables equals less CO2 overall in pretty much every real world case.
Data sources in CO2 per KW: UK: https://grid.iamkate.com/ USA: https://www.eia.gov/tools/faqs/faq.php?id=74&t=11
Sure, I agree that it helps, but only as long as you are emitting co2 as an alternative. Not sure whether comparison to USA is a good one since they ditched new nuclear plants after Three Mile Island accident. Try comparing against France though - they are the greenest and most reliable energy producer out there (maybe Scandinavian countries are better, but they have excellent predispositions). And then we have Germany, which went diehard renewable with the side effect of becoming one of the biggest European polluter.
Germany definitely has a tonne of renewables, but then is still like 25% coal which is why it has high energy emmisions. It has much cleaner energy than it did before adopting renewables though, so still seems like a reason to think renewables are a positive?
It's 100% untrue that Germany's recent pursuing of renewables is the reason it pollutes so much per KW.
Then France has a similar amount of renewables to the UK but with a much cleaner mix after that (basically more nuclear and less gas).
I'm wondering if I've misunderstood your initial point because I'm not seeing any reason to suggest increasing renewables doesn't reduce emissions? Only that there's more to CO2 per KW than just categorising stuff as "renewable" vs "non-renewable", which I don't think anyone is doubting?
Sorry to go so hard on this, but this stuff really matters. We don't have a lot of time left to reduce the most extreme impacts of global warming, and nobody benefits from muddying the waters on the clear benefits of renewables.
I guess we are stating the same, just from different perspectives. About Germany, you are correct that it isn't just their push towards renewables, it was a combination of ditching nuclear power and going full renewables. The real world outcome was huge pollution. That was indeed reduced by renewables (each year more) but still, it was enormous and it's still pretty huge and will be for a foreseeable future unless they come with enough surplus of renewables and huge energy storage. I don't see the later coming soon, though. The France does it right, they rely on nuclear.
You say (correct me if I'm wrong) that renewables (even without storage) are reducing emissions because they reduce fossil fuels usage, and you are definitely right. I'm saying that that's not enough, we have to ditch fossil fuels entirely and if/when that occurs, renewables without storage are not that useful since we will have to rely on stable non-co2-emission power source - which is only nuclear today.
Hey, it's a healthy debate.
Edit: formatting
That's probably propaganda from the oil company. They try to slow down the adoption of renewables by making it look harder than it is.
Fact is: You can start deploying renewables immediately. Every kWh that comes from solar does not come from coal, oil or gas. That is a win. Install renewables first, think about storing the excess power later. That is the best way to go!
Germany enters the chat...
Pumped hydro, hydrogen, batteries. The solutions are readily deployable and economcally viable.
Are they, though? Can you list some bigger storage facilities based on either H or batteries? Like ones that would power a city for few days, for example.
I can't but it's also not necessary. There are no conditions were no energy from renewables is produced. You have to cover peaks and shift electricity around a bit. The missing parts are interconnection and, dependend on price, overbuilding.
I can guarantee you that there are conditions when sun and wind aren't producing a thing or very low output, like during night you are at mercy of wind (hydro is another story, is more stable but even there we experience droughts). So, what do you do when all three (night, no wind and drought) hit you like for a week?
Edit: typo
In the EU, hydrogen. Either by fuel cell or burnt in hydogen ready NG plants. Wouldn't be my first choice but thats whats gonna happen.
Could be, however hydrogen is really tough to handle plus green generation is around 50% efficiency (something like that). Also imagine having huge hydrogen volume and there is a spark...
Well... It's the current strategy.
Also, the same could be said about NG [efficiency about 30%-55% and also a little bit flameable].
Strategy doesn't mean it will be actually implemented or it's the best. For example, Ursula instructed the transportation guy to try to implement Hyperloop. Shall I say more? :) There is also strategy to ditch fossil fuel cars soon....
Now you are getting away from arguments...
You think? I'm saying that we can have a strategy, but that doesn't guarantee the outcome. Again, show me a city scale energy storage today. So, until we have one, it's vaporware. Basically this strategy is based on what exactly? Hope?
The strategy is being implemented, infrastructure being build. Electrolysers and hydrogen ready NGs are planed and build. New NG infrastructure is hydrogen ready. What else are you expecting? Should things magically materialise?
Let's continue the conversation after a couple of years?
Ok, have it your way. Hydrogen Supply Outlook 2024: A Reality Check
Awesome, I win! But seriously, I do hope we pull something off ASAP, being hydrogen or some sort of battery or whatever.
Have you read the article? Hydrogen is developed... fast...
In most jurisdictions, tripling renewables doesn’t get us to a place where we’re generating more electricity than we can instantaneously use. The few places where it is possible can usually export excess electricity to neighbouring jurisdictions that still rely heavily on fossil fuels.
We still have a depressingly long way to go before we’re at the point of renewables generating “excess” energy that needs to be stored.
I think solar will just drop in price so significantly that energy storage will be possible by pure scale. If you get paid to use electricity (which already happens during the day in summer), it doesn't matter if your efficiency is terrible. It's not elegant but it'll get us close to net zero. Unless we blow all of our energy on stupid shit like generative "AI"
Yes, but where you will be storing the excess energy?
Either electro-chemically in batteries, but they might not get energy dense enough for seasonal storage.
Or chemically by creating Hydrogen, Methane or Ammonia. Those are very energy dense and except for Hydrogen easy to store with existing infrastructure. Currently it is just prohibitively expensive, because the net efficiency is bad, especially for Methane and Ammonia.
So without an Oracle I can't say which it will be, but one or more of those will work if the world is committed to net zero.
Yes, exactly, today we don't have a viable solution for large scale energy storage, perhaps we'll find something useful and economically viable (though price shouldn't be the factor since we are talking about devastating future if we continue the way we are) in future.
Hydroelectric dams. Pump water uphill when the energy isn't needed for something else. Hydroelectric is a good variable energy source too. Probably not very efficient, but simple.
I think pumped hydro is reasonably efficient, but requires specific terrain in order to be practical to build. Batteries are getting cheaper, and since grid storage doesn't have the stringent weight and volume requirements that vehicles do, a wider range of chemistries (not just lithium) can be used.
I really hope to see more developments in the realm of gravity batteries. In many cases they are not geographically constrained, given that it only requires vertical space and mass. Ideally, the land already has high variation in elevations, but the storage capacity can still be increased in areas with little vertical space by increasing the mass of the weight being lifted/lowered.
I'm sure you know this, but for curious readers: pumped hydro is also a gravity battery, but it requires two bodies of water at differing elevation. This means it's limited to coastal areas and places like dams. It's also limited by the smaller capacity reservoir between the two bodies of water; the amount of water moved cannot exceed the maximum capacity of the upper body, nor can it exceed the extra capacity of the resevoir of the upper body.
Yes, pumped hydro is really a niche option. As you said, it requires specific terrain - good luck when you have a flat country or no water nearby. It also tends to destroy the nature to some extent.
Storage tech is indeed the laggard.
The most readily available form of stored energy is still natural gas.
We really need to change our energy pricing and taxation to reward green ways to store energy better.