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Comment by curiousllama | Hacker News Reader

Super cool, but not going to solve the question of renewable energy at scale.

Farmers have been doing things like this for generations. American Homesteaders - settlers of the sometimes-rather-arid Great Plains in the US - used windmills for exactly this purpose in the 1800s.

We know renewable energy is super useful under specific circumstances (remote/underdeveloped electrical grid, low power, low need for consistency). Another example in the US is emergency phones on the highway - solar panels power those too, and have for a decade or more.

The critical question is whether it can overcome those specific circumstances and be useful in developed electrical grids with strong needs for high power and consistency.

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I don't think that's true, for example renewables were responsible for ~50% of the energy generated in the UK in Q1 2020[0], and Germany claims it's ~40%[1] and Sweden claims it's ~55%[2].

These aren't perfect numbers, but they clearly demonstrate renewable energy is deployable at national grid scale.

[0]: https://www.edie.net/news/10/Renewables-accounted-for-record...

[1]: https://www.cleanenergywire.org/factsheets/germanys-energy-c...

[2]: https://sweden.se/nature/energy-use-in-sweden/

The only problem I have with that, is that renewables can mostly only be treated as a bonus. Trying to rely on them for baseline power means you have to put out a LOT more capacity than you'd need with fossils.

IMO baseline being nuclear and the rest being mostly renewables (With HEAVY reliance on pumped storage power plants, as a sort of capacitor) is the way to go to minimize emissions.

Renewables today are displacing energy 1:1. So, directly offsetting the fuel that would have otherwise been burned.

You're correct, that there is not a 1:1 reduction in fossil capacity through the construction of renewable capacity. But the fossil capacity is used less, as the marginal cost of the renewable energy is near zero.

Most pumped hydro today (at least in the US) was built during the nuclear build-out because nuclear can't easily be "load following." So, we had to build out additional infrastructure with low capacity factor.

IMO, tax emissions, let the free market figure it out.

For context: I live in austria, where we have the alps that provide a large amount of storage capacity.

Sadly we never got that nuclear power plant.

I wonder if Germany actually will start to decommision all nuclear plants in 2022. From what I've heard they had some insane corruption in storing waste and not the best reactor designs.

Your rumors are untrue. Germany has one of the best reactor designs (the Konvoi) which was the basis for the new European Pressurized Reactor (EPR).

Also, there is no corruption around storing waste because we aren't storing waste yet anywhere outside nuclear facilities which are supervised by the government and the IAEA.

Wow it looks like there has been some deep cleansing of articles about poor radioactive storage in Morsleben from a few reputable outlets. I'm not going to waste my life busting that censorship. Censoring those articles rather proves my point about corruption.

IAEA failed in Iran due to political posturing from europe. Europe has broken more than a few core international organizations. I'd rather not trust them to not cover up anything else for europe.

AFAIK they are already decomissioning nuclear plants. And replacing it with coal or gas. [1]

[1] https://cna.ca/news/germany-replaces-nuclear-coal-ghgs-skyro...

Germany could try to rely on the EU nuclear program but it's likely to be co-opted by France and their nuclear program.

> Renewables today are displacing energy 1:1. So, directly offsetting the fuel that would have otherwise been burned.

Except they are not. Otherwise Germany wouldn't be one of the dirtiest electricity producers in Europe.

I don't know why EE supporters keep ignoring the fact that any electricity not produced by wind and solar despite being needed will be produced by gas or coal which is why Germany is massively investing into new gas plants and a second gas pipeline to Russia (Nordstream 2).

You cannot solely rely on wind or solar which are intermittent and have a low energy density.

We have a solar array on the house. A lot of the Dc to AC solar inverters used in residential installs use the grid to match the frequency of the AC.

The downside is with no grid power the solar system doesn’t work to power the house. There are systems that can but they’re more money.

Take a look at online UPS systems. They convert incoming power to battery voltage, keep the battery charged, and output via an inverter that's made to run without being tied to the grid. They shouldn't be that costly if you can find them without large batteries, instead just hooking them up to your own.

Transfer switch to a very small inverter run off a battery; add your loads one-by-one and you should be fine during a prolonged outage (and as long as there is sunshine...)

can you directly use the DC as a reserve source? like, install car plugs in the house? there are lots of smaller everyday electrical gear for this standard

It's actually a much more interesting question than you might expect. Lots of modern appliances could run perfectly on DC of around the RMS voltage. For example the most modern fridges rectify the incoming mains to drive a brushless DC motor, this allows them to run at an appropriate speed rather than using bang bang control. Even an an induction hob, you might think it was most reliant on having an AC waveform but actually they need a much higher frequency so again they rectify the incoming mains.

Obviously it's not quite that easy, for example an oven uses resistive heating elements which would work fine on DC, however, the relay in the control circuitry wouldn't be able to switch a DC voltage.

That works for small cabins and lighting, as a 12v car outlet requires the same thickness of wire as a normal AC outlet. This is somewhat popular to do if you don’t need to use any high power appliances as then you can skip needing an inverter.

The 50% solution with CCGT making up for variability seems to be working just fine. Wind is a lot more consistent than you think, especially offshore. Does mean we're dependent on gas for the medium term.

Nuclear and pumped storage takes a very long time to build. The other storage systems are starting to make inroads - tiny ones so far, but growing rapidly. The "fast frequency response" market provides them economic support.

> The 50% solution with CCGT making up for variability seems to be working just fine. Wind is a lot more consistent than you think, especially offshore. Does mean we're dependent on gas for the medium term.

It does not work fine at all. Germany is one of the dirtiest electricity producers in Europe.

France emits 50 grams of CO2 per produced kilowatthour while Germany produces 400 grams on average:

> https://www.electricitymap.org

Germany also has the highest electrity prices in Europe:

> https://ec.europa.eu/eurostat/statistics-explained/index.php...

NASA also disagrees that gas plants are a good solution:

> https://www.giss.nasa.gov/research/briefs/kharecha_02/

That's because Germany still uses a lot of coal.

It seems to work, but this is about at the limit of what it can achieve - the UK is having to switch off renewable power sources increasingly aggressively to stop them from going any higher for grid stability reasons, and pay them quite a bit to do so.

The ability of utilities to incorporate renewables seems to have improved over the years. I'm sure it will only get better. In particular the approach of handling excess production by producing "green" hydrogen and storing it in the natural gas distribution network seems promising.

Germany needs 1.6 TWh of electricty per day. If you know the caloric value of methane for example, you will be able to calculate the amount of methane you need to synthesize to just store the electricity of one day which will be roughly 3.2 million gas trucks (45.000 liters each).

There is a reason why the UK is building or planning new nuclear power plants in Hinkley Point, Sizewell and Bredwell.

The German gas network can store 200TWh. I believe that power to gas has a bright future. Check out what Hydrogenics is doing. Also, storage doesn’t have to be day scale to be useful.

There's no need for baseline power in any power grid. The only type of power needed is peak power. You could run a grid on 100% natural gas peaker plants. The only reason to add baseline or intermittent power is if they're cheaper than the peaker plants or have some other advantage like being more green.

Yeah the base load debate seems to often get supply and demand mixed up. It's actually supply driven (old power plants are slow to start and stop and want a number to run at without wasting too much money).

https://www.abc.net.au/news/science/2017-10-12/renewable-ene...

"Technology has moved on from base load, and now you want flexible power. And that's what demand management, batteries and pumped hydro is," says Professor Andrew Blakers, director of the ANU Centre for Sustainable Energy Systems.

"If you have an increase in demand, a coal power station will take hours [to meet it], a gas turbine 20 to 30 minutes, batteries about a second, demand management about a second, and pumped hydro will take anywhere between 20 seconds and two minutes."

I meant environmentally independent power sources as being baseline power. Probably bad wording on my part.

You can not guarantee, no matter the capacity of power storage, that you never produce too little power over a long enough period.

This is the basis of my opinion that the closer to 100% renewable you get the faster the amount of additional capacity you need rises.

Something like 1/x over-provisioning[1] needed, where x is the percentage of environmentally independent power sources.

[1] Not sure if that is the right word.

Conventional plants need to be over-provisioned too, because of the possibility that one or more plants have a malfunction and have to shut down, possibly during a period of high load.

Put another way, it's probably more likely that they'll be some sort of equipment malfunction than we go an entire month with no wind.

Providing redundancy through independent mechanism (over-provisioning, storage, diverse sources) helps a lot.

But you're right. A grid that's 99% renewable with a natural gas peaker providing that last 1% will be a lot cheaper than a grid that's 100% renewable.

Working in that industry, my eyes roll whenever I see someone talk about "baseline" power.

You are right in that there is no such thing as "baseline" generation really. And thermal plants also need to be over-provisioned.

There is dispatchable and non dispatchable power, the former being plants that can alter output on demand.

Base-load is the point which the 24 hour cycle of demand doesn't go below. It's pretty much just a number.

Who occupies the base of the generation stack and will stay running during low demand, is the one who is cheapest. If wind is cheaper than nuclear, it will displace nuclear. The people who say "IMO we need nuclear for baseline and renewable for peaking" completely miss these facts.

The way it is going is renewable at the base of the stack and dispatchable power filling in the gaps, be that during peak or periods of low renewable output.

> The way it is going is renewable at the base of the stack and dispatchable power filling in the gaps, be that during peak or periods of low renewable output.

Very good idea to run gas plants with 490 grams CO2 per kWh instead of nuclear power plants with 12 grams CO2 per kWh, indeed.

France produces 50 grams of CO2 per kWh while Germany has 400 grams on average:

> https://www.electricitymap.org/

Your ideal model for producing electricity actually hurts the environment as the times where gas plants need to run are much more often than you think.

"dispatchable power" doesn't necessarily mean gas, it could mean storage.

Also nuclear is only weakly dispatchable, something the comment you replied to misses. So it is not suitable for filling the gaps.

A 100% nuclear grid will need dispatchable peak power as well, be it gas or storage.

> There's no need for baseline power in any power grid.

Go to smard.de, check "Market data visuals" and "Electricity consumption->Actual consumption" and you will be presented with the baseline which is never below 40 GWh in Germany at any hour.

Sure, baseline demand exists. But I'm talking about supply. If you have a system that can supply 120GWh at any time then it can also supply 40GWh at all times. If it can't supply 40GWh at all times then it obviously can't supply 120GWh at any time.

For the past two years (2018 2019) capacity factor of nuclear power in France has been around 70% mainly due to maintenance according to RTE (1)

For reference best UK offshore wind farm had 55.3% capacity factor in 2019 and UK offshore wind average capacity factor was 40.6% in 2019 (2)

(1) https://media.rte-france.com/bilan-electrique-2019-2/ 379.5 Twh produced, 63.1 GW installed, 68.7% capacity factor

(2) https://energynumbers.info/uk-offshore-wind-capacity-factors

Not far from so-called "baseload"

That's quite misleading though. You can choose and schedule maintenance slots so they don't overlap all at once. Much harder to do with wind, hence you get 0MW output at some times, and massive overgenereration at once causing very negative electricity prices.

Yes and sometimes you have unplanned 680 MW to 0 with "baseload" nuclear:

https://www.energylivenews.com/2015/12/15/unplanned-shutdown...

Wind is intermitent but predictable. Loosing a turbine will not make the plant production go to zero (albeit loosing transmission will but same for all power plants).

One nuclear reactor out of 57. Wow, that's really a problem.

On the other hand, we have times in Germany when wind and solar are producing less than 1% of their installed power.

Pumped storage, like all hydro can be the cause of major emissions depending on how much and what they flood. Anything with forest and suddenly they're actually worse than coal (in terms of Climate Change emissions, not the other nasty shit)

A good visualization of those numbers: https://www.electricitymap.org/map

I don't think we disagree at all! I think we agree on the core question (can it be used at scale), and that there have been GREAT strides in developed countries towards an answer ("yes!").

I just think Opium farmers in Afghanistan fail to demonstrate a unique use case: great idea, but we've known this works for a while, so this use case isn't not exactly a panacea of novel insight.

At least 40% of the renewables used in Europe (I think it is over 60% now) is biomass, so it's arguable how renewable it really is.

renewable energy including wood for heating yes.

But for electricity it's only about 6% in the EU, see table page 7 of the following PDF:

https://www.agora-energiewende.de/fileadmin2/Projekte/2018/E...

Pretty sure that's renewable. I think renewable just means we can replace it/make more of it, which isn't the case with oil. You can renew the supply.

It depends how fast you use them. Are we using biomass at faster than replacement rate? Probably. And cutting down forests for biomass does irreparable damage to forest ecosystems.

Which cause 290 grams of CO2 per kWh according to IPCC unlike nuclear which just accounts for 12 grams of CO2 per kWh.

These numbers are highly misleading as:

- they count biomass as renewable which is not (it is responsible for 230 g CO2 per kWh)

- these numbers are accumulated, i.e integrated values which don't help much because you buy electricity when you need it, not vice versa

- despite Germany being 50% renenwable, we still are one of the dirtiest electricity producers in Europe with 400 g CO2 per kWh on average while France has 50 g on average per kWh

- we also have the highest electricity prices in Europe and the second-highest electricity prices world-wide

> https://www.electricitymap.org/

> https://ec.europa.eu/eurostat/statistics-explained/index.php...

Oh, and Germany is replacing nuclear with gas and coal, which means replacing 12 g CO2 per kWh with 490 g CO2 or even 800 g CO2 per kWh:

> https://www.br.de/nachrichten/bayern/nachfolge-fuer-gundremm...

> https://www.stuttgarter-zeitung.de/inhalt.energieversorgung-...

> https://www1.wdr.de/nachrichten/ruhrgebiet/datteln-vier-geht...

The so-called Energiewende will have cost Germany 520 billion Euros by 2025:

> https://www.welt.de/wirtschaft/article158668152/Energiewende...

Yet it had hardly any impact on our emissions in the energy sector:

> https://www.umweltbundesamt.de/bild/treibhausgas-emissionen-...

If you want to understand why the Energiewende (replacing everything with renewables) doesn't work, go to smard.de, click "Market Data Visuals" and "Actual Generation" and you will see that there are recurring points in time where the power generation of wind and solar is around just 1%.

Note: Before you suggest storage: Germany consumes 1600 GWh electricity per day. We have only 40 GWh of pump-storage capacity, so that won't work. And in case you want to suggest "Power2Gas", I suggest having a look at the caloric value of methane and calculate how much methane you will at least need to generate if you want to store 1.6 TWh of electricity.

>- they count biomass as renewable which is not (it is responsible for 230 g CO2 per kWh)

Renewable doesn't mean 0 CO2, it means you can renew the fuel. We know how to turn that CO2 back into biomass, it just takes a field. We historically haven't known how to make large quantities of oil without expending some other non-renewable fuel.

I personally feel with solar prices so cheap renewable power is a solved problem what market is waiting for is batteries to get cheap enough. I am expecting in the next decade tesla powerwall type batteries to be in every house even apartments for storing power for night time use now will these batteries be owned by the house/property owners or leased from the power companies that is something the market will decide.

> I personally feel with solar prices so cheap renewable power is a solved problem what market is waiting for is batteries to get cheap enough.

Germany consumes 1.6 TWh of electricity per day. The battery of a Tesla S has 100 kWh. So you will need to charge 16 million Tesla S batteries to provide the electricity of Germany for just one day.

Good luck trying to implement that.

The answer to that question is the answer to the critical question “Can we use solar to help replace oil, natural gas, and coal.” That’s really a different thing that what this article talks about. This article is about how solar can help people and the economy today.

The main purpose is the article is the show the afghan farmers thriving with solar but doing so by exporting a product that is considered very harmful to the rest of the world. It’s thrilling, captures attention, is topical, and has more substance than your average clickbait.

> low need for consistency

I believe this could be extended significantly. If we really wanted to. There is no a real need to run say an auto-manufacturing plant 24/7. There is no reason why we couldn't run it only on sunny days and give everyone a paid day off othertimes.

No reason, other than, you know, making manufacturing much more expensive.

If a car company knows it can sell 1 million cars a year, it needs to be able to manufacture 1 million cars a year. If they operate their plant 24/7, their plants need to have enough throughout to build 2 cars a minute. However, if they plan to only operate during sunny days, their plants will only operate probably a third of the time, so they need to build three times as many factories, buy three times as many machines, build three times the number of manufacturing lines, and hire more employees.

Or produce one third of the cars. I don't think there is a shortage of cars in the world.

This is not possible in market capitalism. Companies will produce as many cars as people will buy. Even if one company decides to restrict its production, another will fill its place. You need central planning to decide how many cars are to be built, and to be sure, if you look at the centrally planned economies of communist countries, they definitely did produce less than third the number of cars their citizens enjoy now.

> You need central planning to decide how many cars are to be built

Isn't it what every non-banana-republic is doing already, indirectly [0]. And if we get serious about achieving net-zero economy and price carbon accordingly the car makers will have to adjust even further. They could plant trillions of trees, or they could make fewer cars. Up to them. I am just saying that in my view making fewer cars will be a more viable economic decision. And consumers will redirect their purchasing power to something else.

[0] https://en.wikipedia.org/wiki/Vehicle_emission_standard

> Isn't it what every non-banana-republic is doing already, indirectly

Emission standards do reduce number of cars produced, to be sure, but much less than you propose. Mostly what they do is make the cars kinda suck, especially compared to how expensive they are. People buy cars anyway, and put up with it.

I’m all for renewables but this is an unacceptable compromise. Seriously, this isn’t how large business can operate.

Really it's the wrong example. The best way to distribute "demand response" is in systems which have a big thermal mass attached to them. You can turn an industrial freezer off for half an hour without anyone noticing.

An 80/20 compromise where most of the power is from renewables and the rest made up by CCGT seems very much within reach for the UK.

And finally, ideally, the last 20% shifts to gas turbines fueled with clean hydrogen.

The UK has about 1000 TWh of hydrogen storage potential in onshore salt deposits that could be solution-mined to make underground hydrogen storage caverns.

"Technical potential of salt caverns for hydrogen storage in Europe"

https://www.sciencedirect.com/science/article/abs/pii/S03603...

Siemens is providing a gas turbine generator that will run on 100% renewable hydrogen as part of the HYFLEXPOWER demonstrator project:

https://press.siemens.com/global/en/pressrelease/hyflexpower...

Siemens and General Electric both have roadmaps for gas turbines running on pure hydrogen:

"Siemens’ Roadmap to 100% Hydrogen Gas Turbines"

https://www.powermag.com/siemens-roadmap-to-100-hydrogen-gas...

GE Power "Hydrogen fueled gas turbines"

https://www.ge.com/power/gas/fuel-capability/hydrogen-fueled...

Most current turbine models are already capable of running on a methane-hydrogen blend.

I like to highlight these projects because people sometimes mistakenly think that seasonal-scale storage with hydrogen also requires breakthroughs in scaling fuel cell technology. Evolutionary developments in gas turbine technology will also make it practical.

The UK has opted for nuclear. They are building and planning in Bradwell, Hinkley Point and Sizewell.

Given the high costs of Hinkley Point C, I suspect that the new reactors planned for Sizewell and Bradwell may not actually be built.

"Hinkley Point C nuclear plant to run £2.9bn over budget"

https://www.bbc.com/news/business-49823305

French power company EDF said the new nuclear plant it is building at Hinkley Point C will cost up to £2.9bn more than thought.

It raised its estimate for the project, in Somerset, to between £21.5bn and £22.5bn, blaming "challenging ground conditions".

It also said the risk of the project being 15 months late had risen.

...

These cost overruns will not hit UK consumers. However, a new way of paying for further nuclear stations, such as Sizewell, is being considered.

Under this new model, consumers would see costs of construction added to their bills as the project went along. It means that customers could be exposed to cost overruns.

That is why today's announcement is important and why EDF will find it harder to make the argument for building Sizewell.

> this isn’t how large business can operate

Why not?

The capital costs of something like a automobile factory ($500 mil+) pretty much force you to run 24/7. Also, automobiles are labor intensive to produce, so idling the workforce alone would cost more than building more power.

Something low capital, low labor and high energy like steel recycling has already shifted to operate when electricity is cheap.

In the current economic environment, yes. But suppose we transitioned into a new economic reality. Imagine that net-zero-carbon global economy is a hard requirement. Imposed by god or something. I guess adjustable demand would be a feasible option then.

Even then it might not change the vehicle factory much, as it moves from a high $ capital cost, to a high environmental capital cost that you will want to spread over as many vehicles as possible. The easiest thing to reduce capital costs would be to stop painting vehicles and switch to stainless steel skins as paint is one of the single largest capital expenses in building a car.

Downstream suppliers of the plant might change, mainly ones that have a high energy, low capital(either $ or environmental) process.

Socialism doesn't work. It has been proven multiple times.

That's an interesting idea but production lines cannot just be stopped and started like that - you could carry much more produced inventory to make up for lost days but that will be expensive.

Everything is expensive when it comes to climate mitigation/adaptation. The question is what is more expensive - say CCS or stopping/starting production lines.

> Everything is expensive when it comes to climate mitigation/adaptation. The question is what is more expensive - say CCS or stopping/starting production lines.

Or, you know, just use nuclear power:

> https://www.giss.nasa.gov/research/briefs/kharecha_02/

> There is no a real need to run say an auto-manufacturing plant 24/7.

There are plants like steel furnace that have to run 24/7 as the iron has to be kept melted. If solidifies, you will never be able to get it liquid again.

You are about two decades behind the times in your understanding of the renewable energy grid application situation.

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