Comment by jillesvangurp
2 days ago
The article doesn't mention a technology that deserves some attention because it counters the biggest and most obvious deficiency in solar: the sun doesn't always shine.
That technology is cables. Cables allow us to move energy over long distances. And with HVCD cables that can mean across continents, oceans, time zones, and climate regions. The nice things about cables is that they are currently being underutilized. They are designed to have enough capacity so that the grid continues to function at peak demand. Off peak, there is a lot of under utilized cable capacity. An obvious use for that would be transporting power to wherever batteries need to be re-charged from wherever there is excess solar/wind power. And cables can work both ways. So import when there's a shortage, export when there's a surplus.
And that includes the rapidly growing stock of batteries that are just sitting there with an average charge state close to more or less fully charged most of the time. We're talking terawatt hours of power. All you need to get at that is cables.
Long distance cables will start moving non trivial amounts of renewable power around as we start executing on plans to e.g. connect Moroccan solar with the UK, Australian solar with Singapore, east coast US to Europe, etc. There are lots of cable projects stuck in planning pipelines around the world. Cables can compensate for some of the localized variations in energy productions caused by seasonal effects, weather, or day/night cycles.
For the rest, we have nuclear, geothermal, hydro, and a rapidly growing stock of obsolete gas plants that we might still turn on on a rainy day. I think anyone still investing in gas plants will need a reality check: mothballed gas plant aren't going to be very profitable. But we'll keep some around for decades to come anyway.
Plausible alternatives to cables include ships full of synthetic diesel, ships full of iron, ships full of aluminum, or ships full of magnesium. Inside China HVDC cables are indeed carrying solar power across the continent, but the Netherlands have not managed to erect any yet. Cables provide efficient JIT power delivery, but they're vulnerable to precision-guided missiles, which Ukrainians are 3-D printing in their basements by the million, so the aluminum-air battery may return to commercial use.
There's at least one HVDC cable connected to Netherlands, Norned: https://en.wikipedia.org/wiki/NorNed .
As probably everyone knows, Netherlands is very flat and Norway very mountaneous. Norways is also very rainy. So it's a match made in heaven - Norway's mountain reservoirs can act as balancers for dutch wind power.
>Budgeted at €550 million, and completed at a cost of €600m
Amazing.
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And to Denmark:
https://en.wikipedia.org/wiki/COBRAcable
While Denmark in term essentially is a trading hub for electricity between Scandinavia, the UK and continental Europe.
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Thank you for the correction! It's also immune to quadcopters.
As well as electricity to ammonia, ship it around the world by boat and then crack or burn it at the destination. or just use it as-is.
Yes, ammonia is another candidate.
Ships carrying energy are a pretty easy explosive target as well.
Local ressilence is needed in any case and mass produced batteries can provide that safety.
Diesel, iron or aluminum, from your parent post, are difficult to explode… (personally, no clue about magnesium); and the point of the latter two is that you can “store” energy by upstreaming its consumption when power is available, you don’t necessarily need to produce an actual reversible energy store.
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Yes, it's easy to imagine cases where people go around sinking ships; narcosubs, Red Sea oil shipping, and Russian warships in the Black Sea are of course dealing with that threat currently, but as hostilities escalate it's likely to increase. But energy in the form of shipped fuel intrinsically provides some minimal level of such local resilience—for it to work, you need at least a stockpile of fuel big enough to last until the next ship is expected to unload, which is orders of magnitude longer than the milliseconds before a cable cut affects you—and can provide arbitrarily large amounts of it.
The metal fuels in particular have the merit that you can use them in precisely such mass-produced batteries rather than to produce thermal power. As I alluded to in my grandparent comment, aluminum-air batteries were mass-produced in the 01960s.
We have quite a bit of experience transporting hydrocarbons . . . .
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The Netherlands has “erected” multiple HVDC links
> ships full of iron
At first I thought you meant "embodied energy" or some such.
Iceland "exports" geothermal energy by converting bauxite ore into aluminum.
Australian could "export" renewable energy by domestically converting iron ore into steel.
Yes, but remove the scare quotes; I'm talking about exporting those materials to people who burn them for energy, in most cases in batteries. The round-trip efficiency of that process is not great, but I think should be around 70% for aluminum, and better for iron and magnesium; and the specific energy (MJ/kg) for those metals is significantly better than for conventional hydrocarbon fuels.
Ukranians are 3d printing millions of missiles in their basements?
They might use rotating wings to fly instead of jet turbines, but yes.
EDIT: To make things clearer, the word Missile is quite old, and predates rockets. missile is any object that is propelled somehow to hit a target. So even a stone launched from a sling by a caveman is already a missile. The other guy mentioned precision guided missiles though... and he is still correct in the word usage there.
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As long as we all realize you can’t 3D print precision-guided missiles without, well, the guidance bit.
The guidance bit should be quite cheap now though, compared to decades ago. Some combination of MEMS backed up with GPS.
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Transmission lines are a interesting idea, but expensive.
Once solar is cheap (like now, as it already is), you can put in 3x what is needed on a sunny day, and power everything on cloudy days. Solar runs on cloudy days. Night obviously requires a different solution. Start by installing solar over all parking lots.
To think that you won't be able to run a 100% solar/wind grid is a bet against human ingenuity. If generation in excess of peak demand was installed of solar/wind, there are many promising approaches to deal with generation shortfalls. Batteries, load shifting, an electric vehicle fleet that charges during the day and powers the grid at night if the owner opts in, precooling a home with AC during the day to a low set point so AC isn't needed at night, H2 storage in salt caverns, pumped hydro, aluminum smelters that operate during excess power periods, the possibilities are infinite.
It won't be hard. Don't bet against human ingenuity.
Solar over parking lots is so good. it creates power, shade, and reduces reflected heat.
Especially at workplaces or shopping malls, where most people park during the day, you can also install lots of EV chargers and use produced power onsite.
And you can't make a parking lot any uglier.
I think this would work for the summer months. Overnight storage is manageble/cost-effective by load shifting/battery storage/etc. This is now estimated at about $100/MWh ($0.10/Kwh).
Seasonal storage is a completely different story. For my own panels, production in Nov/Dec/Jan is about 20% of that in Apr/May/Jun, and this is typical. That means that you either need 15x solar capacity of what you need on a sunny day, or enough storage to bridge those 3 months, two orders of magnitude storage more than we would need to store electricity overnight.
You are right. A different way of thinking of this is that we'll be able to saturate whatever cable capacity there is with excess solar and wind in order to charge whatever battery capacity needs charging. It's a careful balance between time shifting solar and wind with batteries or shifting it in space with cables. They complement each other. The natural consequence of people installing more solar, wind, and batteries than they need is running surpluses most of the time. Which means that whenever there's a local shortage, cables are a way out because there's plenty of energy in the system. The more excess energy there is, the more attractive cables get.
It's not an either or thing. And this will be a self optimizing system as well. It won't be up to grid operators anymore. If people need more power, they'll get some even if the grids won't provide it. And if they need it to be more reliable, they'll fix it anyway they can. Which includes using batteries, generators, and whatever else works.
Hydrogen for energy production is a bit of a fantasy IMHO. Awful battery. Expensive to create. And there are plenty more profitable uses for it than sacrificing it as a simple methane alternative. Honestly, burning it is a bit desperate. If you have all this valuable hydrogen and burning it is the most valuable thing you can imagine doing, you're doing it wrong and missing out on some big dollar amount of more sane shit you should be doing.
Cables are expensive mainly because of policy. They are mainly made using commodity materials (copper, aluminium, etc.). Cable manufacturing isn't expensive. Installing them isn't rocket science. Land disputes on the other hand are cripplingly expensive. Solve that and cables become cheap. Geothermal works the same way; not that hard. Drill some holes (oil companies are really good at this) and that's most of the work. Getting permission to do that is the hard and expensive part.
You missed a huge upcoming one: EV's. I firmly believe that paying EV owners with vehicle-to-load capability will soon be used to smooth out peaks and troughs in the grid. Maybe in the future even systems that use DC fast charging contacts to get the huge DC voltages needed for an external inverter capable of powering several houses.
As in, "an electric vehicle fleet that charges during the day and powers the grid at night if the owner opts in"?
Any country relying on international cables for electricity would need to build and maintain full local backup power capacity. The combined cost of cables + backup may be more than storage cost. (Of course there are many factors which affect all these costs)
You might say "any country relying on international pipelines for gas would need to build and maintain full local backup capacity", except they didn't. Hence the Russia/Ukraine war causing all sorts of problems.
To be fair, many countries have several months worth of gas reserves.
==the Russia/Ukraine war causing all sorts of problems.==
Problems, yes. Catastrophes, no. It's not clear that they "needed" full backup capacity.
"Full capacity" backup looks different when you have sufficient batteries on the grid. Building enough backup generation to hit peak capacity would entail a lot more gas plants than building enough to hit average capacity and using batteries to supply the peaks.
Most states have sizeable underground gas storages, often reusing old oil and gas fields. The capacity being from weeks to months of normal use, possibly much longer with some rationing. This mostly turned out to be sufficient to enable a quick switch to LNG and other sources.
> maintain full local backup power capacity.
Not necessarily. If connectivity is broad and the network graph is decentralized, rerouting should cover some of the backup.
For example, if Luxembourg goes to war with Belgium, and Belgium shuts down the lines to Luxembourg, then they can reroute via Germany or France (provided they have lines there, obv). But if Spain gets beef with France, and France cuts the lines, they cannot easily reroute. So Spain would need more backup and more independence (and prolly cables to Italy and Africa?). Point being:
It helps to have stable bi-lateral relationships between countries that choose to connect their grids and economies. This kind of stability is a good thing. The current instability with long relationships being questioned and falling apart is a bad thing. And where you say cost, I say investment. Because energy is a valuable commodity and being able to buy/sell energy via cables has value.
Most renewable energy investments have decent, easy to calculate returns on investment. That's why this stuff is so popular with investors. And that's also why I don't think current policy changes in the US matter long term. It just slightly increases the time to a return on investment. But you still get a return. So, companies will continue to look at batteries, solar, and indeed cables with or without government support. And even a little bit of tariffs (aka. taxes) won't stop that.
Recent history is a very, very good reminder that political relationships between countries (or more generally political powers) are extremely fragile and the only reliable constant in these kinds of systems is change and stability isn't permanent, unfortunately.
Even the EU with it's very tight integration between member states is seeing a lot of pressure to tear itself apart again from the inside, despite the very real costs thĺis would bring.
Norway, Denmark and The Netherlands are all part of the European Union. Would you make the same claim if we were talking about US states? (With Texas being a special exception)
Norway is member of the European Economic Area, not of the European Union, together with Iceland and Liechtenstein.
https://en.wikipedia.org/wiki/European_Economic_Area
It's a risk management thing. "Can a trade dispute or undersea 'accident' lead to mass blackouts?"
There is one error there, Norway is not in the EU
Cables can be a great option in certain places but geography and politics limit where they can be used. No one is going to run a cable across the Pacific Ocean so that Russian solar power can supply evening peak demand loads in western North America.
No, but it might make sense to run them from the east coast to the west in America.
Interesting side effect is that this reliance on cables introduces a dependency on copper which already is in short supply and which can be mined only in specific regions.
So it re-introduces some geo-political dependencies. Not in the way fossil fuels or unranium do, because a copper cable won't "burn up" to produce the energy, but they do need some upkeep.
Another dependency this introduces is the network itself. A failure in specific regions could lead to massive blackouts (Like recently in spain/portugal) or could even become political pressure instruments like currently the russian-natural-gas-pipelines in Europe are
The Spain/Portugal blackout happened when network management failed to predict a workable source mix. Basically human error.
Political pressure is hardly a renewables problem, and is more likely to mitigate it than make it worse.
Currently we get a lot of energy by shipping it as physical cargo around the world through various unstable regions after it's produced by hostile regimes - which is not exactly a recipe for reliability.
https://www.reuters.com/business/energy/investigation-into-s...
Right, they are blaming the "thermal powersources"(non-renewable) for the waveform of the grid collapsing.
They also initially said that there was "high ion flux" from the sun too.
I am not EE or in power gen but it smacks a bit more of politics than analysis.
https://www.eng-tips.com/threads/spain-and-portugal-power-gr...
It's a non-issue. Copper isn't that short in supply.
A typical car uses ~25kg of copper - that's enough for approximately 0.5m of HVDC.
The EU currently produces 12mln cars annually, down 3mln from the 2017 peak.
In other words there should be no issue with ramping up demand for the equivalent of 1500km of HVDC annually in the EU alone - a rate much higher than the local bureaucracy could manage issuing permits for.
Do any of these HVDC lines really use copper? I think aluminum is much much more common.
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Cables can be made out of aluminium, so that's not really an issue
Not just "can be". For transmission lines (which is what we're talking about here) aluminum is used exclusively.
HVCD Was supposed to be the answer for china’s big renewable energy surplus out west while most of its energy needs are in the east, but for some reason it hasn’t worked out so they are leaning on nuclear and coal more for eastern power needs. I guess when the imbalance is huge, it’s not that easy. They could move more manufacturing out west, and I think they are doing that to a point, but water supply becomes an issue at that point (and it will always be easier to move energy than water!). Still, I wonder if we will see the rise of cities like Lanzhou that have cheap electricity, the same thing happened for Seattle and aluminum smelting via cheap hydro power (also why boeing started there)
They don’t invest in gas much because they have to import it all, though it will be a long time before they use electricity for cooking as opposed to natural gas or propane.
UHVDC is progress is "fine", I think utilization is 60-70%, ideally it would be 80-90% but hurdles now mostly political, many central govs still want to prop up local coal, so new policies on national unified electric / spot market by 2026. Current UHVDC capacity is ~150GW, utilization around ~100GW, PRC peak demand ~1000GW, i.e. UHVDC transmitting like 10% national power, could be 15%. Rollout for next 10 years is to hit ~25%, something like 300GW (70-80% from western renewables), assuming peak power demand grows to peak 1200-1500GW. But this is based on outdated 14th 5-year plan projections (~2021), PRC currently on trend to 1800-2000GW peak. Don't know if there's new policies to scale UHVCD accordingly.
This seems to be quite far from reality?
Nuclear power is a minuscule part of the Chinese grid. 4.4% and shrinking and with their recent number of construction starts will likely land on ~2% of the grid mix.
Their coal usage has started to shrink.
How can they lean on technologies they have started to replace with renewables and storage?
UHV (both AC and DC) has worked out as planned in China, so much so that there's still more under construction today and scheduled for the future.
It seems premature to write that all off given it's ongoing.
Nuclear is also expanding as planned, as a small percentage of renewable power, and China's coal use is peaking and starting to level and planned to fall in the short term future.
The interesting nuclear project to watch in china is their third generation salt reactors .. their small pilot has been running for a whilke, their second gen is completed (?) and starting to return data at the next scale up, and the third generation plant is in the initial construction phase (to be modified on the fly as results come back from the pilot and second gen plant.
https://en.wikipedia.org/wiki/Ultra-high-voltage_electricity...
I do not feel as optimistic about any uptick in cables as I do about solar and wind. Solar and wind can grow through a multitude of small, plug-and-play projects. Cable projects like HDVC are still giant, long-term punts.
A lot of the wind projects could be classified as "giant, long-term punts".
https://en.wikipedia.org/wiki/Hornsea_Wind_Farm
What exactly does that mean?
The project you linked to was completed pretty quickly and is supplying 2.5GW to the UK grid
This is literally the problem. Transmission is desperately needed, much more than generation right now. The issue is that it's hard to explain to people why this is, and even when they understand they react like you do.
RENEWABLES NEED TRANSMISSION!!! We need to be building unprecedented Manhattan project levels of transmission, yesterday! But instead we will put some solar panels on a car park and feel like we did our part. Solar is the easy part. Storage and/or transmission is the hard part.
And I'd still much rather pay a utility every month for electricity (and have them be responsible for maintaining and upgrading the infrastructure) than install and maintain my own solar plant on my roof, for the same reasons that I'd rather pay utilities to provide me with water and sewer service than have my own well and septic system.
With sufficiently cheap storage, no transmission is needed. There's a tradeoff, and batteries are rapidly improving.
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Is this whole "new set of cables" factored into the CO2 emissions equation? We're undoubtedly going to use massive amounts of energy to mine the metal, melt it into wire, transport it to the site, build the towers, etc. Is that energy "green" ?
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There's geopolitical implications. Solar is long stability, short conflict. It's easy to cut undersea cables, it's easy for instability arriving to one the landlocked countries in the middle of transit. This creates systemic risks that are asymmetric with respect to offense and defense.
Many would see this as an invitation to retreat from solar, but I view it as the opposite. Widespread solar will cause peace via the capitalist peace theory, similar to the role that trade plays in staking everyone in mutual stability. Stability will become a public good that everyone will want to preserve. Solar will be another part of the international diplomatic-cultural-economic web that binds countries together in mutual interest.
Resiliency can be figured out with creativity, it's not something to give up on at the first challenge.
To be fair, natural gas and oil shares similar systemic risks, whether it's pipelines open to sabotage or water transits being subject to blockade, such as the Malacca dilemma that China would face if it invades Taiwan. But at least with solar, it won't ruin countries with the resource curse, and in principle it doesn't give a small number of countries leverage since anyone can produce this fairly basic commodity.
That was the idea behind Germany’s energy dependence on Russia. Let’s call that experiment not successful, shall we?
The Russian government didn't see it as a Russian dependency on Germany.
As far as the dependency direction goes, Germany didn't start a war with Russia, so the simplistic example isn't enough to disprove anything. If you want to disprove it, do so by explaining how Russia was dependent on Europe.
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> similar to the role that trade plays in staking everyone in mutual stability
That's a nice idea in theory but isn't worth much in practice if one of the trade partners has 19th century style imperial ambitions.
they were cut off from trade as much as possible (of course there have been rogue nations, but those weren't equivalent in trading/buying power) - and that's one of the reasons, they're not winning the war, even though they were superior in almost all metrics, not at least military and economic power.
if nothing else this will serve as a warning and a cautionary tale for future aspiring conquerors.
How far do cables generally move power now in terms of hours, meaning time zone offset? This might seem like an odd formulation, but.
I /think/ formulating the problem this way means that 12h=power is always relevant. So: where are we?
Aside from your question (which I would rephrase as, How expensive is it to send electricity to a different time zone), another important question is, How expensive is it to ensure that the electricity continues to flow if our country's government angers some other country's government and that country has an effective military?
Better grid connections helps with variable weather but it does nothing for solar biggest down side.
Seasonal variation from December to May is enormous.
Storing months of power is a problem with no known solution.
“No known solution” is categorically false [1]. Economics is the issue
1. Generate hydrogen or other synthetic hydrocarbon fuels from electricity; flow batteries, saltwater batteries, and a myriad other chemistries; compressed air; hydro, etc etc
They're not really solutions if they're not achievable in practice though. Otherwise why not add nuclear fusion to the mix?
To give some example: Switzerland is roughly electricity neutral over a year, but there's a significant winter/summer imbalance of about 5TWh. To add enough storage to compensate this imbalance, you would need to:
- cover about 2% of the country in batteries
- build about a thousand pump storage stations: despite the Alps covering about 40% of the country, it's not clear if you would have enough valleys to flood
- hydrogen looks a bit more reasonable, if we don't look at the costs, you only need to store a few millions m3 of liquid hydrogen. The gas storage in Germany for instance are quite a bit larger than that, but hydrogen is also significantly harder to store.
And all of this is to use once a year essentially! None of it looks practical or affordable (a pump storage station costs a few billions a piece for instance).
Just to add: overbuilding and using the excess in low capital-intensive applications.
North south connections enable solar power from Africa to be used around the year. And while solar is down in the winter, wind production usually peaks. If you have thousands of km of cable, there is a lot of power that can be moved around.
buckle may be referring at least partly to the north-south landmass imbalance.
inb4 someone tries to invent floating solar farms to try to fill the Pacific with, lol.
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Ah yes, what Europe needs once more is to become existentially dependent on a region that is both culturally and geographically distant and where Europe has very little ability to enforce and police it's interests.
Have we learned nothing from the 2022 energy crisis? The number of starry eyed suggestions here about distributed worldwide power networks and load balancing is astonishing given the realities that we actually live in.
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Power2Gas and using the existing infrastructure for gas storage is a known solution for storing months of power. It might not be the cheapest solution though.
Methane storage is only like a few weeks at most.
Storing months worth of power is not something we do with natural gas or even oil today.
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Power2gas+solar/wind produced energy is a lot more expensive than natural gas and requires solar/wind to routinely overproduce.
...hence why there isnt much of it. It either requires subsidies or for natural gas to be taxed more.
Windless night produced electricity from stored solar energy via windgas is still cheaper than nuclear power produced on sunny, windy days though: https://theecologist.org/2016/feb/17/wind-power-windgas-chea...
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for the rest (as the sun shines again after some time) storage sounds like a viable alternative to the list in your comments...
other than that I agree
Despite all the great technology and improvements over the years, consumer energy in Europe has never been so expensive.
We have started to tax carbon in form the of the ETS system while now LNG keeps being the marginal producer in the grid.
Meaning - the interconnection queue for storage and new renewables is absolutely enormous but getting enough online to meaningfully alter the electricity bills will take years.
In the USA, eg California, the cost of building out the grid we need (to achieve netzero) is mostly borne by retail consumers. Versus industry and data centers. (IIRC)
Obviously, this creates huge push back, threatening the transition to renewables.
The Correct Answer remains federal policy and support. Just like the New Deal Era's electrification of our country.
Few years ago I was super hyped about HVDC across the ocean too. LCOE over batteries seemed no brainer.
Now I am not so sure anymore, especially most of the power is going to be powering AI datacenters and it's far easier to locate datacenter near cheap solar than put tons of cables around the world.
> All you need to get at that is cables
I don't understand your point. Power grids are a thing, and these enormous battery banks are attached to them.
It's true that power grids are independent from each other, but it's not a simple matter to just connect them all and observe a huge benefit as solar farms in Africa power the US or something. When everything is working that is certainly a possible outcome, but when things break, the operators of these grids need to know what the other grid operators are doing, and supply must be routed to demand correctly or you'll just create more outages. power grids aren't a simple mesh where any substation can power any home.
Dude, the sun always shines.