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‘Energy independence feels practical’: Europeans building mini solar farms

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Re: ‘Energy independence feels practical’: Europeans building mini solar farms

#351

Post by giantg2 »

barbazoo wrote: post #315
giantg2 wrote: post #311

Are they using EU manufactured solar panels? If not, I don't feel like this is real independence.

It's a different kind of dependence. Sure you need China for this particular panel you're buying now but from then on you are no longer dependent on them. Compare that to oil and gas which has to continually be shipped. And no one says that we won't figure out how to produce these things ourselves one day.

We can produce them already, but they're too expensive. You are still reliant on China etc continuously shipping panels because panels will need to be replaced and expanded over time. Sure, it's a smaller volume, but still the same sort of problem.

Re: ‘Energy independence feels practical’: Europeans building mini solar farms

#352

Post by Moldoteck »

adrianN wrote: post #350
Moldoteck wrote: post #349

Earlier quoted context omitted.

and did you consume it when it was produced?

I guess I consume most of it. There are 4kWh of batteries connected to the panels. I set my dishwasher and my washing machine to run when production is high.

so you have a ±2k eur battery on top of probably 1.6Kw solar modules costing about 1k eur, attached to balcony and generating about 5kwh/day? And probably with very nice sun conditions because otherwise you'd need more solar.

Now let's take french household prices per kwh of 25ct/kwh. It means at 5kwh/day consumption the bill would be 450eur/y. So a 3k investment in this case would pay for itself in 6-7 years.

For a german household with highest prices in EU payback would be in about 4y assuming 40ct/kwh

But realistically many will not even buy a bess not being able to capture all solar output and many will have worse solar conditions. I'm not sure balcony solar in Germany generates even 1% of total solar production in the country despite streamlined installation process

Re: ‘Energy independence feels practical’: Europeans building mini solar farms

#353

Post by mbgerring »

yawaramin wrote: post #245
ericd wrote: post #204

Earlier quoted context omitted.

It's aluminum, glass, silicon, and some conductive metal. Surely you all have those materials. And even if you don't make them yourselves, they aren't make and then burn like fossil fuels, they are durable infrastructure, you don't have to replace them often - they have an expected lifespan of >30 years. Buy as many as China will sell you, and once you have more than enough installed, you're good for a long time, reg…

> expected lifespan of >30 years More like > I think being reliant on the fossil fuel supply chain for so long France isn't. And they are net exporting their (nuclear fission) electricity to their neighbours who shut down nuclear power plants.

The observed lifespan of DER assets is consistently longer than the manufacturer’s (or insurance company’s) rating

Re: ‘Energy independence feels practical’: Europeans building mini solar farms

#354

Post by adrianN »

Moldoteck wrote: post #352
adrianN wrote: post #350

Earlier quoted context omitted.

I guess I consume most of it. There are 4kWh of batteries connected to the panels. I set my dishwasher and my washing machine to run when production is high.

so you have a ±2k eur battery on top of probably 1.6Kw solar modules costing about 1k eur, attached to balcony and generating about 5kwh/day? And probably with very nice sun conditions because otherwise you'd need more solar. Now let's take french household prices per kwh of 25ct/kwh. It means at 5kwh/day consumption the bill would be 450eur/y. So a 3k investment in this case would pay for itself in 6-7 years. For a…

The batteries where 800€, the panels about 400 and the inverter I think around a hundred (all from Amazon). All the stuff I needed to attach the panels to the balcony and the cables where surprisingly expensive.

Re: ‘Energy independence feels practical’: Europeans building mini solar farms

#355

Post by PaulDavisThe1st »

theoreticalmal wrote: post #336
PaulDavisThe1st wrote: post #207

Earlier quoted context omitted.

my understanding is that micro-inverters send an "up and running" signal encoded over the DC wiring to the main inverter, and that this is used to detect micro-inverter failure. that is an entirely different problem than the one in the GP comment, i think.

“Rapid shutdown devices” do this. Microinverters have the same “grid is down, turn off” logic as a main inverter

Again, entirely different to the point being raised.

You have 4 neighbors, all with grid-tied inverters, all of which will do rapid shutdown if the grid goes down.

The grid does go down ... but are there circumstances under which the presence of neighboring inverters will "hide" the grid being down from each inverter, and so they will keep delivering power back to the grid ?

Re: ‘Energy independence feels practical’: Europeans building mini solar farms

#356

Post by horsawlarway »

PaulDavisThe1st wrote: post #211
horsawlarway wrote: post #113

Earlier quoted context omitted.

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 di…

The dilemma here for me is twofold: (1) while it makes sense to me to distribute generation, because there are not really any significant economies of scale other than purchasing power, it doesn't make sense to distribute storage which, IIUC, has huge economies of scale. (2) being fully off-grid where I live requires homes that can be heated in winter with heat pumps that require less than mid-winter generation level…

I think there are some interesting conversations to be had with regards to your first point.

Our grid infrastructure isn't cheap. We need a huge amount of equipment to do the voltage conversions to make power lines semi-sane. We also need a ton of space, maintenance and equipment to run the wiring, install the transformers, handle substations and distribution, etc...

My suspicion is that if you account for that, local storage is cheaper. But I think we're still finding out where battery tech is going to settle.

I'd be having a very different conversation if we hadn't introduced LiFePO4 (LFP) batteries, and realistically - these have only been on the market ~15 years now, and only really generally available for 5 or 6 years.

These are already pretty incredible batteries. A bank them the size of a washing machine will power most residential homes for days, cost under 10K, and be very safe. Prismatic LFP cells run ~$100/kwh (not theoretically, right now: https://www.18650batterystore.com/products/eve-mb31-grade-a-...)

If we see a similar upgrade with Sodium (and it's looking more and more real, multiple commercial products have hit the market last year) - then I think a decade from now we'll really start to wonder why we're wasting so much land and spending so much on grid equipment if you can just install a small bank of batteries for a couple thousand dollars and call it done.

Will you still have economies of scale with storage? Probably. Will those outweigh costs to transmit that to where it needs to go? My hunch is no.

---

On a darker note - individual generation and storage is WAY more robust to military disruption. No central location to bomb to knock out power for a whole city.

Re: ‘Energy independence feels practical’: Europeans building mini solar farms

#357

Post by shafyy »

mixermachine wrote: post #335
shafyy wrote: post #310

Earlier quoted context omitted.

Do you own one of these? If yes, are you happy with the quality?

No I don't own them. Some people here: https://www.mydealz.de/share-deal-from-app/2753917 mention as a downside that you have to connect to the manufacturer cloud to get the live production data from the interverter. Otherwise it is truly "plug everything together and it works".

Ok thanks!

Re: ‘Energy independence feels practical’: Europeans building mini solar farms

#358

Post by Gasp0de »

mmlkrx wrote: post #299
Gasp0de wrote: post #295

I live in Germany, installed a micro solar system in September 2024. Since then, we've been producing 45% of our electricity consumption ourselves. This has saved us 550€, while the initial cost was around 800€. So this September, after 2 years, the system will have paid for itself.

Could you provide more details? 800 Euros sounds very cheap while being able to produce 45% of your electricity needs. Did you mount it on your roof or a balcony or wall? How much power does it produce? Very curious to hear more details or even recommendations (I too live in Germany).

Hi, sorry I'm late to respond. The price was something like this: 150€ Hoymiles HMS-800W-2t 300€ 4 Trina Solar 445W Full Black panels 100€ Shelly Pro 3em (not necessary but I wanted to see how much we feed in) The rest was construction materials and small stuff. We have mounted it on our roof, 900W East, 900W West. One east and one west panel are wired in parallel and connected to one MPPT of the HMS-800W. We're producing around 1.3MWh per year.

Re: ‘Energy independence feels practical’: Europeans building mini solar farms

#359

Post by Gasp0de »

mixermachine wrote: post #306
Gasp0de wrote: post #295

I live in Germany, installed a micro solar system in September 2024. Since then, we've been producing 45% of our electricity consumption ourselves. This has saved us 550€, while the initial cost was around 800€. So this September, after 2 years, the system will have paid for itself.

Crazy thing is, the cost of these systems has gone down even further since then. You can get a 800w plug-in solar set with panels and an inverter for around 200€. Shipping might be 70€ or you can pick it up locally at the dealer. Add another 50-100€ for attachment material and you are good. So for 250 to 400€ you can get a system that will break even latest after four years, likely earlier.

Yes, although to be fair we have around 1.8kWp, plus roof installation material, plus shipping.

Re: ‘Energy independence feels practical’: Europeans building mini solar farms

#360

Post by barbazoo »

giantg2 wrote: post #351
barbazoo wrote: post #315

Earlier quoted context omitted.

It's a different kind of dependence. Sure you need China for this particular panel you're buying now but from then on you are no longer dependent on them. Compare that to oil and gas which has to continually be shipped. And no one says that we won't figure out how to produce these things ourselves one day.

We can produce them already, but they're too expensive. You are still reliant on China etc continuously shipping panels because panels will need to be replaced and expanded over time. Sure, it's a smaller volume, but still the same sort of problem.

Solar panels last for decades, you have to import oil every single day. How is it the same problem? And that's not even assuming we won't figure out how to build them cheaply ourselves.
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