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Posted by vrganj 10 hours ago

‘Energy independence feels practical’: Europeans building mini solar farms(www.euronews.com)
116 points | 115 comments
bokohut 1 hour ago|
Several recent HN posts about "time" and these correlate superbly in relation to the now obvious, to nearly all, global energy issues. Those proactive in a reactive world are often mocked and laughed at until as such passage of time is achieved for those only reactive to learn of the proactive's hindsight choices. For those in the United States aware of the 'behind the scenes' energy grid issues this insight reflects that prices will not be dropping for those electrons we all so depressively require daily just like our air and water. Energy grid decentralization is occurring with the actions of each individual and this article supports exactly that because no one alive can survive in our modern world without those electrons. "Necessity is the mother of invention" only now resonates for some while the futurists here that acted long ago acutely understand this growing trend.
pjc50 10 hours ago||
Fairly boilerplate article, but the bit that is news is the UK balcony solar permitting. Better longread: https://solarenergyconcepts.co.uk/post/plug-in-solar-uk/

Government press release with a long list of pull quotes: https://www.gov.uk/government/news/government-to-make-plug-i...

(I note that in the alternate universe where Ed Miliband became PM because he didn't eat a bacon sandwich, we could have had this a decade ago. It is embarrassing to be beaten on environmentalist regulatory efficiency by Germany)

oliwarner 3 hours ago||
British industry and standards bodies think this is an unsafe plan.

Of course they would because it's work being taken away from them but it would be allowing people to plug generators into ring finals with unidirectional breakers. It's not even guaranteed that the circuit is protected by anything newer than fuse wire or an MCB. No guaranteed earth leakage detection. No guaranteed surge protection. Relying on the cheapest inverters to sync frequency accurately. And

I have more faith in German standards and work ethic than our own.

fnordpiglet 1 hour ago|||
I find it interesting because often the best way to achieve a safe building code is to learn by allowing with basic guard rails and iterating as things happen. This isn’t ideal for the rare individual impacted by the “things happening,” but collectively we refine and iterate. Our current standards weren’t arrived at by navel gazing - we got the codes we have by experience. It’s hard to realize that from the present that you can’t reasonably learn without doing and by constraining without learning prevents growth and learning.
zdragnar 53 minutes ago||
Are there lessons on safety that need to be learned here? We already know what the happy path looks like, and we've plenty of lessons on what the unhappy path will look like.

It isn't as if electric charge coming from balcony solar panels is some new magical-seeming type of electricity.

labcomputer 39 minutes ago||||
“Unidirectional breakers” aren’t a thing for AC circuits.
jonatron 26 minutes ago||
https://www.bgelectrical.uk/uk/circuit-protection/devices/rc... Right there, both bidirectional and unidirectional breakers.
formerly_proven 1 hour ago||||
The situation in germany is essentially the same, but that's why net supply by these is limited to 800 W. I don't think anything changes w.r.t. earth leakage, why would the presence of the solar supply change anything from the RCD and fault point of views, respectively?
mytailorisrich 1 hour ago||
Not expert but one difference is that in Germany the standard wiring is radial circuits with 16A MCBs while in the UK it's ring wiring with 32A MCBs.

So in the UK we have 2.5mm^2 wires in a ring on a 32A MCBs... Of course a 2.5mm^2 wire is rated ~20A so any issues with the ring (sockets still work since connected from the other branch) can burn the wire before the MCB trips...

formerly_proven 1 hour ago||
The "standard" wiring is 1.5mm² on 16A MCBs which are rated to trip at 1.13-1.45x nominal current (so 18-23 A). So this is already mildly improper because you can pull elevated currents continuously and dramatically shorten the life of the insulation.
ZeroGravitas 7 hours ago|||
He also removed the effective ban on onshore wind construction that was introduced a month after he lost the election, restarting after a decade of lost opportunity.

This Trump-level idiocy that is just never mentioned, even as people blame the gas burned in england on windy days as a cost of wind curtailment, when the curtailment is more a like a third of the cost. Burning gas to power people who chose not to build turbines is the other 2/3rds.

In the alternate world that is tens of billions of gas costs avoided to date and tens of billions more in future.

mytailorisrich 6 hours ago||
At the same time they are banning wind turbines leaders (Chinese companies) from opening factories in the UK... [1][2]

[1] https://www.bbc.co.uk/news/articles/c995xjxk97mo

[2] https://www.energyvoice.com/insights/energy-opinion/594763/m...

tim333 3 hours ago||
That seems rather dumb. I wonder why they blocked the Ming Yang thing in Scotland? The UK seems to make quite a lot of dumb energy decisions like blocking UK North Sea gas and then buying North Sea gas from Norway.
mytailorisrich 47 seconds ago||
Yes it is rather 'dumb'. Apparently the policy is to reset relations with the EU so perhaps selling out to Siemens is deemed preferable, it is difficult to follow. And that's the point: Where is the plan? Where is strategic thinking?
mytailorisrich 9 hours ago||
> I note that in the alternate universe where Ed Miliband became PM because he didn't eat a bacon sandwich, we could have had this a decade ago

I read what is happening in exactly the opposite way. To me it shows that Milliand and the government at large do very little with no strategic thinking and no plan (same as the guys before in fairness but this government was supposed to be soo different...) and, in this case, is only reacting in a panic after almost 2 years in office to the pressure of "doing something" because of the Iran war, while also being told (slight mitigating circumstances for Milliband) that it mustn't cost anything. I always picture scenes from The Thick of It/ In the Loop when I imagine how they come up with 'ideas'.

theshrike79 10 hours ago||
Distributed energy production / storage is the key for resiliency in the future.

Every solar farm doesn't need to be China Size - it doesn't even need to be a "farm", just put them on roofs.

And don't let perfect be the enemy of good. Yes there are times when solar doesn't produce energy, but there are also times where it OVERproduces.

te_chris 9 hours ago||
Wild that you're getting downvoted for saying something so obvious. Weird.
9wzYQbTYsAIc 9 hours ago||
Politics of solar, at work
friendzis 9 hours ago||
> And don't let perfect be the enemy of good. Yes there are times when solar doesn't produce energy, but there are also times where it OVERproduces.

When solar OVERproduces you have to literally pay someone to consume that energy, most probably wind farms, which could be producing energy instead. So you pay actually twice. When the solar underproduces, you need to bring in alternative sources, but those now have to cover all their fixed costs and generate return on investment over this limited timeframe, which means the actual backup prices hit stratospheric levels.

What's the actual cost of solar with actual net-billing?

horsawlarway 49 minutes ago|||
Home installations just cut it off. In both of these cases.

I did my own battery backed installation. When I'm underproducing I can shed load (I turn off my AC - almost always that's enough, and it's automated by relay). When I'm overproducing (ex - my battery is full and my load is still not enough to consume input) I just don't let the panels generate more current than I can consume.

Managing grid scale power is different concern, and not particularly relevant to small household generation. Especially not relevant in the 800W category for "balcony solar" (which is much smaller than what I'm working with).

Solar is fucking coming, whether you continue to shove head into the ground or not.

It's just way more affordable. Getting easily more affordable as batteries continue to improve.

I honestly doubt I'll still be connected to a local utility grid for electric 10 years from now, and I live in a region of the US that has considerably cheaper grid power than most areas.

mr_mitm 2 hours ago||||
> When solar OVERproduces you have to literally pay someone to consume that energy,

Can't we just throttle the solar panel? In a worst case, you just pull the plug. It's not like a nuclear power plant which needs to be shut down carefully, or am I misunderstanding something?

tapoxi 1 hour ago|||
Yes that's exactly how it works, it's called curtailment.
tacet 1 hour ago|||
You can limit amount you feed back into network.

Not sure how is situation with home installations, factory i work for runs 150kw plant for our own consumption and don't bother with selling, but i know that we can set up how much we want/are allowed to feed back.

Rebelgecko 1 hour ago||||
Cheap home solar installations usually have a disconnect- do they not use those in larger scale installs?

I'm also surprised they aren't using batteries to capture overproduction. They've been clutch in the US, and we're not exactly pushing the envelope of green energy nowadays

1970-01-01 6 hours ago||||
>you have to literally pay someone to consume that energy,

Here's the thing. That's a rule and not a technical problem. Absolutely no reason to do this other than rules and regulations.

ZeroGravitas 6 hours ago||
Yes, but even more so, it's a good sensible rule!

People don't even bother to argue why it's bad, they've just seen so many headlines telling them it's bad they don't question it.

1970-01-01 5 hours ago||
I'll question it. Why does it exist? Why can't we just shut off the panels or dump excess energy into a metal rod? Why do we need to have a buyer at all?
friendzis 5 hours ago||
Because otherwise the incentive structures for solar-as-baseload, sweeping the actual cost on the consumers, collapse. The system is built on putting equality sign between oversubscribed solar and coal/gas backups during times of undersubscription.
RealityVoid 8 hours ago||||
> When solar OVERproduces you have to literally pay someone to consume that energy, most probably wind farms, which could be producing energy instead.

You don't have to do this with solar, you can just disconnect the panel and have it go a bit hotter. For producers that have a long-ish bringup time, yes, you might need to do this at time.

pjc50 8 hours ago||
The situation is slightly complicated by dispatch order, and domestic solar isn't usually dispatchable at all. Grid-scale farms are.

Wind farms don't consume energy, but there is a real issue with how often they have to be "curtailed" (paid to turn off). That is to a great extent due to issues with grid connectivity between Scotland and the rest of the UK, which are (slowly) being worked on.

leonidasrup 52 minutes ago|||
Wind curtailment is the deliberate reduction of electricity output from wind turbines, despite their capability to generate power under existing wind conditions. This practice is typically implemented by grid operators to maintain the stability of the electrical grid or to address specific operational constraints.

https://www.enlitia.com/resources-blog-post/what-is-wind-cur...

"paid to turn off" Wind energy providers in some countries are compensated for curtailment, this a form of subsidy for renewables. It can be payed directly by the goverment, or it is added to the price of electricity for consumer.

https://www.cleanenergywire.org/news/renewable-curtailment-c...

RealityVoid 4 hours ago|||
My understanding is that all inverters sold at this moment, in the EU, need to have demand response and grid curtailment mechanisms by law.
MagicMoonlight 37 minutes ago||||
No you don’t, you could just ground it. Paying them is a choice.
pstuart 2 hours ago||||
When there's an OVERproduction of energy, that really means there's an UNDER-availability of storage. Battery tech continues it's march towards cheaper prices, and alternatives such as thermal storage are making inroads as well.

It borders on criminal to have abundant energy production be disservice.

ElevenLathe 1 hour ago||
I'm not energy markets analyst, so take this with a grain of salt, but I think the next major breakthrough for solar (not the slow, inevitable rollout we're seeing now) will be when somebody figures out an economical way export this periodic overproduction. There is basically never a time when humanity as a whole has an overproduction of free energy, but at present we also don't have a way to make money turning this surplus into a tradable product (like oil, coal, LNG, etc.) because all the electric-powered processes for making such products (ammonia, methane, primary aluminum production) require big hunks of capital equipment that lose money unless they're operated more or less continuously. Battery, thermal, pumped hydro, etc. help here, in that enough of it can theoretically turn the off-and-on solar/wind power into a continuous load to power your aluminum smelter or whatever. Even better though, would be a cheap electrically operated methane plant that you could afford to run intermittently. This, plus a peaker natgas generating plant make, effectively, a battery of infinite size, or you can sell it to any of the many eager buyers of natgas.

Building a small, prefab, plant like this, if possible, would seem to be mainly a problem of scale, and therefore it seems likely that China will get to it pretty soon.

toomuchtodo 2 hours ago||||
Inverters can be configured with export limits to limit, or entirely halt, energy exports based on market or grid signals. Term of art is "curtailment."

https://en.wikipedia.org/wiki/Curtailment_(electricity)

raverbashing 8 hours ago|||
"If you find dollar bills on the ground you need to pay someone to collect it as litter"

Charge batteries, do electrolysis, or a multitude of other uses (I know some companies do that already)

conorcleary 6 hours ago||
Used 240w modules built in 2010-2012 are worth $60-100 CAD at the moment in small quantities. There will be hundreds of thousands hitting the market (as long as they didn't hit the ground with careless removals) in ~2030+ as microFIT contracts in Ontario expire.

There is no clear path to switching these arrays to Net Metering, as of yet. Prepare for all sorts of unrecycled solar panels and potential loss of renewable capacity that is already installed.

msandford 35 minutes ago|||
Net metering is really, really smart when the installed base is small relative to the fossil fuel power plant capacity. But it doesn't scale forever. Once it gets up towards 20-40% of the fossil fuel capacity, it goes from an asset to a liability.

Suppose I have a 100MW gas turbine. And suppose there's 1MW of solar installed in my generation network. I don't really care if I sell 80MW at noon and 90MW around dinner time and 50MW through the night, or if instead it's 79MW at noon and 91MW at dinner and 51MW at night. The gas costs about the same irrespective of when I burn it so a bit of a fuel shift doesn't really matter.

But take that 1MW and turn it into 20MW and suddenly we go from 80MW at noon to 60MW at noon, 90MW at dinner to 110MW at dinner and uh oh. You see the problem? Whatever losses I endured at noon I don't get to make up for at dinner because my plant only goes up to 100MW and now we're not just shifting when we burn how much fuel, we're literally having to shift the power generation to a different plant.

Is this example precisely accurate? Absolutely not. But it helps you get a feel for the problem of net metering at scale. The grid can act as a battery for a few % of total generation, but by the time you hit some number, maybe 20% maybe 40% net metering turns from a cool math trick to a real cost on the grid.

wat10000 21 minutes ago||
Net metering only makes sense as a way to incentivize solar installations. Looking at the economics, it's not something any utility would offer willingly.

It's like if the grocery store let you give them milk for a credit at full price. (Let's ignore the sanitary/health/quality issues that would come up.) You decide to buy a cow and you drink that milk. Sometimes you need more than your cow can give so you buy extra from the store. Sometimes you need less and you sell the extra to the store. Long term, you use as much as your cow produces on average, so you pay the store nothing. But the store has provided a valuable services to you and has incurred expenses in doing so. They have to keep the lights on and maintain a building and pay workers to handle your transactions but they make no money from you. The only way it would work at all is if they made enough money from their non-cow-owning customers to make up for it, and that can only take you so far.

pjc50 4 hours ago|||
Could you elaborate on this? Why would people remove a working solar system?
jandrese 1 hour ago||
Buildings get torn down. Roof needs a replacement and the owner doesn't feel like it is worthwhile to redo the solar install for panels that only have 5 years of warranty left, or maybe they want to replace them with higher power models with a fresh warranty. There are any number of reasons why someone might need to offload otherwise functional solar panels.
PowerElectronix 1 hour ago||
For european individuals, yes. For european nations, not in the least. They try to avoid independent consumers and producers of energy with all the regulations they can throw to them.
myrmidon 55 minutes ago||
What nations are you talking about? E.g. in Germany, you can buy up to 7kW of panels, screw them onto your roof, wire them up with controller and battery and feed up to 800W into local grid, no one is gonna stop you or anything (only thing you need to do is register online with the grid operator if you have >2kW of panels).

Legislation is, in fact, specifically made so people (i.e. landlord) actually can't easily stop you from doing this.

leonidasrup 1 hour ago||
[dead]
comrade1234 9 hours ago||
Related, there's also a boom in at-home battery installations.

https://www.swissinfo.ch/eng/climate-adaptation/switzerland-...

cjrp 10 hours ago||
The UK previously didn't allow small plug in solar panels (the kind that you just plug in to a mains socket) due to, I believe, safety reasons. This has changed within the last few days https://energysavingtrust.org.uk/solar-roadmap/
lazyasciiart 9 hours ago||
I believe it’s only legal in Utah so far in the US: they legislated it last year, and apparently half the country is expected to pass a copy-paste version in their next sessions
TYPE_FASTER 3 hours ago||
Current state by state status (not my site): https://pluginsolarusa.com
mytailorisrich 10 hours ago||
It hasn't changed... yet. The media noise is because the government has announced that they were reviewing current rules with the aim of allowing "balcony solar" by the end of the year.
misja111 9 hours ago||
Can anybody explain how these plug-in solar panels work? I am suprised that it's possible to just plug them in to your wall socket.

For instance, isn't it complicated to have their output be in perfect sync with the frequency that comes in via the electricity net? Because to me it seems that if they won't, you will have lower benefits or even a net minus after plugging it in.

pjc50 8 hours ago||
> isn't it complicated to have their output be in perfect sync with the frequency

Not especially, given that the inverter has a microprocessor in it. All it has to do is measure the phase of the existing grid.

I don't have references for how it's actually done, but one obvious approach is simply to wait at each zero-crossing for a new half-cycle to cross a voltage threshold before turning on the output. This also implements the requirement to drop out if the grid goes away. It is probably also possible to measure during the "off" side of inverter output PWM, in the same way that variable frequency motor drivers work.

wyldfire 1 hour ago|||
I guess if you can solve phase alignment then another big problem is grid capability?

If everyone plugged one in, could the transmission network reliably deliver the power generated where it's needed? I thought that was a serious long term challenge for utilities wrt solar.

canpan 9 hours ago|||
Not a specialist, just from what I heard: There are two things that make it work. First they are not really "independent" like the title says. They sync with the grid frequency. If the grid is down they shut off for safety. The other reason it works is that the grid power inside the home is just what you get as incoming power 〜230V. For example, I think in the US you get 240V or so delivered to your house, but 120V from the plug.
myrmidon 6 hours ago|||
Typically, you have "dumb" panels connected to a mppt-controller/charger/inverter box which is connected to batteries and and electrical plug. This controller tunes voltage/current that is taken from the panels, optionally manages the attached battery and measures and feeds into the grid connection.

Some systems are capable of running in isolation from grid (providing 230V AC on their own), but this is less common and often unnecessary.

mytailorisrich 9 hours ago||
My understanding is that plug-in solar inverters do sense what is coming from the grid and phase-sync to it with a PLL, and also adjust voltage accordingly.
ForHackernews 9 hours ago||
They are going to start selling solar panels at Lidl, a German-owned grocery store chain https://www.independent.co.uk/extras/indybest/house-garden/l...
1970-01-01 6 hours ago||
"Suddenly" is horrific evidence that the government has no idea how to do long-term plans.

Wait until you tell them you can run cars entirely on electricity from a solar farming. I'm sure they will ignore you until the price of diesel reaches four-digit territory. 1000p today? If only we didn't have to pay these incredible prices, what a miracle that would be..

michaelteter 1 hour ago|
It's not that government has no idea, it's that around the world, too many "leaders" are directly or strongly indirectly being enriched by the fossil fuel industry and their support industries.

So politicians have a choice: do what's right for the people, or gain more power/money for themselves. Not every one of them chooses poorly, but enough do that it is difficult for real progress to be made.

metalman 10 hours ago|
to answer the first question in the article

"Many consumers want to know how long it will take them to make back the upfront costs of solar"

my answer is that the payback is imediate, right from the first moment watching as energy is generated out of thin air, and the sudden relief from getting off the energy angst missery-go-round, and the sheer borring inertness of solar pv as it does the thing with zero detectable effort, is gratifying and relaxing in a way that money never gives.

I will add that solar pv is increadably robust, and damage tollerant as well, you can drive a claw hammer through a panel, and while it does not improve the performance, the degradation is actualy not that much, and it will continue to function for years

rdtsc 1 hour ago||
>> "Many consumers want to know how long it will take them to make back the upfront costs of solar"

> my answer is that the payback is imediate,

So if I pay $35k for an install, I get a $35k check the first time I connect it to the grid? Pretty sure it doesn't work that way. But it would be a nice subsidy from the government if they were really motivated.

I guess you're saying you start to feel good and validated to have spent the money by seeing _some_ savings every billing period. It's hard to argue with feelings of course, but that's not not the original concern. People want to know how long is it going to take: 1, 5, 10 years or ... never (if panels degrade or break before it will never pay off) to pay off their investment.

9wzYQbTYsAIc 9 hours ago|||
The mindset shift towards “how many hours of computer usage did that one panel enable” is like the mindset shift from learning calculus, in some ways. Not quite a paradigm shift, but you gain a new appreciation for conservation of use when it’s a difference between choice of $/kW/hr and “wow, the panel powered that for most of the day”.

At the same time, many people will just use a solar calculator or watch or yard lights etc, oblivious to it all.

Show people a solar powered laptop, a solar powered phone, or a solar powered tablet, then they will be impressed.

Remember the craze about solar powered car competitions?

permacompute + solar would make for quite the $100 laptop competition.

zowie_howie 7 hours ago||
Is it immediate? Sure, there is satisfaction that you are using 'free' electricity. But it does have an upfront cost. I calculated that it would take over 11 years to recoup the investment based on our current usage. Given we already get cheap night-time rates to charge the car and run appliances, it is hard to justify.

Like many UK houses, we have gas central heating too. I guess if we had a battery too (more investment) then we could switch to using electric oil-filled radiators, though they would not heat the whole house. And we could install a hot water tank.

I guess for new builds there is a real opportunity, but for an existing household I'm struggling to see how it works - and I want it to!

pjc50 6 hours ago|||
I don't think it ever makes sense to switch to electric radiators. It might make sense to switch to a heatpump, but you need to avoid being hugely overcharged by the installers and there are flow issues if you have 8mm piping.

This ROI calculator looks reasonable: https://ukcalculator.com/solar-panel-roi-calculator.html - note that it subtracts the install cost for you, so any case where the final figure is positive is profitable. But of course that depends on whether grid prices go up or down in the next decade ...

mytailorisrich 4 hours ago||
Well France did move to electric everything (cooking, hot water, heating) in the past thanks to ample nuclear electricity production (and possibly not too harsh winters). Unfortunately they let their nuclear programme decay and are struggling now (EU grid integration does not help)...

I think a big part of the push to install heat pumps now is that it is understood that electricity production is in dire straights, taking into account that the transition to EV requires a lot of electricity.

ZeroGravitas 6 hours ago|||
Are you talking about rooftop solar?

For an 800W balcony system your background house usage is likely to be enough to self consume most of it.

You'd wouldn't be able to run even a small oil heater except maybe in peak summer.

It's a good match for working from home as it's a small amount of power spread over daylight hours.

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