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Solar and batteries can power the world

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Re: Solar and batteries can power the world

#461

Post by friendzis »

toasty228 wrote: post #428
friendzis wrote: post #245

Earlier quoted context omitted.

> A properly insulated house in any temperate climate require very little heating or cooling. A "properly insulated" house still requires something around 0,5 W/m2/K. Modeling a moderate 120 m2 house in the coldest months when the temperatures hit 15-20 negative you still need 2,5 kW of heat with domestic hot water on top. Put in the efficiency of a heat pump and you are still easily looking at half a mega watt-hour…

> 0,5 W/m2/K. That was a good number in 1980 lmao (or in the US maybe), passive houses are often 1/5th of that. I'm talking 25cm+ of rockwool in the walls, 40cm on the roof and triple pane windows, mostly facing south, reasonably shaped house that conserve heat by design, etc. 0.5 W/m²/K is a good value.... for a window, certainly not for the overall house, for a wall it wouldn't even pass code in most of Europe > Th…

> passive houses are often 1/5th of that. > 0.5 W/m²/K is a good value.... for a wall it wouldn't even pass code in most of Europe

There's a mix of miscommunication and wat. I'm using approximate floor area values here, not perimeter walls. 0.1 W/m2/K for a WALL is definitely not a "passive" house, that's barely A++.

> I'm talking 25cm+ of rockwool in the walls, 40cm on the roof and triple pane windows,

Yep, this gets you something like 0.5 realistic, maaaaybe up to 0.3 in the models.

Re: Solar and batteries can power the world

#462

Post by friendzis »

toasty228 wrote: post #428
friendzis wrote: post #245

Earlier quoted context omitted.

> A properly insulated house in any temperate climate require very little heating or cooling. A "properly insulated" house still requires something around 0,5 W/m2/K. Modeling a moderate 120 m2 house in the coldest months when the temperatures hit 15-20 negative you still need 2,5 kW of heat with domestic hot water on top. Put in the efficiency of a heat pump and you are still easily looking at half a mega watt-hour…

> 0,5 W/m2/K. That was a good number in 1980 lmao (or in the US maybe), passive houses are often 1/5th of that. I'm talking 25cm+ of rockwool in the walls, 40cm on the roof and triple pane windows, mostly facing south, reasonably shaped house that conserve heat by design, etc. 0.5 W/m²/K is a good value.... for a window, certainly not for the overall house, for a wall it wouldn't even pass code in most of Europe > Th…

> > > That's entirely unrealistic to cover with batteries with current battery technologies alone

> It already is a reality for many people.

Megawatt-hour level home-battery installs? Show us a picture. That's literally a room full of batteries. The actual reality is having ten or so kilowatt-hours to balance rooftop solar.

Re: Solar and batteries can power the world

#463

Post by cauch »

SoftTalker wrote: post #444
cauch wrote: post #392

Earlier quoted context omitted.

Why do you say "optimized for 1-2h peaks"? The typical electricity demand has a trough during the night for few hours, then a first peak in the morning, than a second less-deep trough in the middle of the day (sometimes with a bump around lunchtime), than a second bigger peak in the afternoon for 3-4 hours. And of course this varies with season, day of week, regions, ... Not sure why you are saying that renewable you…

Renewable (solar for example) needs enough battery to cover the 12-18 hours a day where the sun isn't shining or is at too low an angle to effectively capture by solar panels. This is far more than covering a few hours of load peak. Solar might actually be a decent peaking power source, as it tends to peak at the same time as demand. But it's not a good base load source; it needs far too much battery buffer.

My point is that to follow the demand, you need ~12 hours of capacity: the trough is during the night around 1-4 am, the peak is mainly in the afternoon around 5pm. So if you have a battery for nuclear, you will charge it during the night and discharge it ~12 hours later.

Not sure about your 12-18 hours, it looks like you want to use the energy during the night, while it is the trough and does not require energy.

Re: Solar and batteries can power the world

#464

Post by mbesto »

morphle wrote: post #452
mbesto wrote: post #446

Earlier quoted context omitted.

Wait, you put 600kWh of batteries on a sprinter van?!? I wanna know more...that's insane (base eSprinter is like ~115 kWh, right?)

eSprinter 2022 is 56kWh. In Europe I'm limited in the size of a battery by the total legal weight of van and it's trailer combined. So I can not tow more weight than 600KWh LFP batteries with this particular van. But with $0.01 cost per kWh it only cost $60 (52,08 Euro) for a full charge, good for 2000 km (Amsterdam to southern Spain). So even though I carry 5.5-6 times as much weight as a small city car around, it c…

But 600 kWh is about ~4k kg, no? Isn't that like the max hauling a sprinter can do? So doesn't this just get you a bunch of range at the "cost" of not being able to haul anything or am I missing something?

Re: Solar and batteries can power the world

#465

Post by morphle »

mbesto wrote: post #464
morphle wrote: post #452

Earlier quoted context omitted.

eSprinter 2022 is 56kWh. In Europe I'm limited in the size of a battery by the total legal weight of van and it's trailer combined. So I can not tow more weight than 600KWh LFP batteries with this particular van. But with $0.01 cost per kWh it only cost $60 (52,08 Euro) for a full charge, good for 2000 km (Amsterdam to southern Spain). So even though I carry 5.5-6 times as much weight as a small city car around, it c…

But 600 kWh is about ~4k kg, no? Isn't that like the max hauling a sprinter can do? So doesn't this just get you a bunch of range at the "cost" of not being able to haul anything or am I missing something?

7000 kg is the maximum a van and its trailer can way by law in Europe. It can haul a lot more.

No, my eSprinter camper is a small room with kitchen, bed and shower. The trailer ways 3500 kg, the eSprinter 2670. I could haul at least 889 kilo more. If I had the bigger motor I could haul twice as much.

Re: Solar and batteries can power the world

#466

Post by coryrc »

jakewins wrote: post #380
coryrc wrote: post #363

Earlier quoted context omitted.

I mostly agree with you, however... You don't need to colocate solar at the point it's used. Utility solar is cheaper than rooftop, by multiple. The last part isn't true. There's no way you're running a home, including heat, entirely of solar in the winter in the Upper Peninsula of Michigan.

Utility solar is cheaper in studies that do not factor in the cost of distribution, but the picture is much less clear when total system cost is considered - not having to pay for expanded distribution grids or new interconnects is a major benefit of residential production. As for the last part not being true, can you clarify? The majority of the earths population lives between the 20th and 40th latitude, the band ar…

I misread you as saying all homes. You're right that anywhere that's sunny year round, a SFH can be self-sufficient for electricity with photovoltaic and batteries.

Re: Solar and batteries can power the world

#467

Post by hamdingers »

declan_roberts wrote: post #443
hamdingers wrote: post #424

Earlier quoted context omitted.

It's a true statement and a real problem. These wildcat megawatt-scale generation facilities built on top of suburban neighborhoods produce an un-curtail-able midday oversupply of electricity driving energy prices into the negative. The power has to go somewhere, SoCal grid operators have to pay real money to neighboring grids to accept the energy being generated while also paying the homeowner who generated it. No g…

I'll believe they're serious about this problem when they stop charging TOU customers PEAK DEMAND prices during the duck curve. They're soaking out of both sides of their mouth.

The reason for that is explained in the comment you replied to, you just have to put the pieces together.

Re: Solar and batteries can power the world

#468

Post by 542354234235 »

wakawaka28 wrote: post #440
defrost wrote: post #432

Earlier quoted context omitted.

We (literally, I know where some are) have 30 year old panels and 95 year old men, their existence doesn't negate an average. Also, PV panels are kinda non uniform in performance, long term studies show that one fifth of them perform 1.5 times worse than the rest. Either way, 20 year lifetimes where you build once and reap the rewards for 20 years is sufficient to put to rest the kind of argument being made about dep…

>Either way, 20 year lifetimes where you build once and reap the rewards for 20 years is sufficient to put to rest the kind of argument being made about dependancies. It's not sufficient. We have had plenty of time to start making all of the critical things we import, and that never happened. In most cases, these things used to be made in the West in the first place. Just because you CAN make a thing doesn't mean it…

The economics of petroleum would be totally different if you had to pay 5x more for crude to replace Straight of Hormuz blocked imports. Weird that it took way less than 20 years for that to hit.

Re: Solar and batteries can power the world

#469

Post by tonyarkles »

ExpertAdvisor01 wrote: post #129
silvestrov wrote: post #51

Earlier quoted context omitted.

Hydro in Norway goes very well with windmills in Denmark. Very simplified: Wind blows mostly in Denmark during the day, so Norway stops hydro during the day and imports electricity from Denmark's windmills. During night the wind is mostly still in Denmark so windmills don't produce much and Denmark imports from Norway's hydro. In this way you can stretch the capacity from hydro using windmills even though Norway isn'…

Also what is probably used in your country is Pumped-storage hydroelectricity . During the day you pump water into the reservoir using wind/solar energy and discharge e.g at night .

Elsewhere in the country yes but lol not so much in the very flat part of Western Canada. I pulled out some topographic maps a few years ago and was quite dismayed at the lack of elevation change suitable for pumped hydro.

Re: Solar and batteries can power the world

#470

Post by wakawaka28 »

542354234235 wrote: post #468
wakawaka28 wrote: post #440

Earlier quoted context omitted.

>Either way, 20 year lifetimes where you build once and reap the rewards for 20 years is sufficient to put to rest the kind of argument being made about dependancies. It's not sufficient. We have had plenty of time to start making all of the critical things we import, and that never happened. In most cases, these things used to be made in the West in the first place. Just because you CAN make a thing doesn't mean it…

The economics of petroleum would be totally different if you had to pay 5x more for crude to replace Straight of Hormuz blocked imports. Weird that it took way less than 20 years for that to hit.

Perhaps, but solar panels will NOT get cheaper as a result of oil becoming more expensive, even if the price hike is somehow permanent. They are manufactured through an energy-intensive process. Unlike the solar manufacturing cost problem, there are solutions to the oil shortage issue for the rest of our lifetimes, most likely. We depend on oil and gas for our existence in many ways, not just for energy.

In the very long run we need to find alternative sources of energy but I think solar is not going to be that solution. Solar is most likely going to be a fringe backup alternative to nuclear power. Batteries have tremendous disadvantages. In the long run some kind of biofuel or synthetic hydrocarbon might win over batteries.

>Weird that it took way less than 20 years for that to hit.

No, it's not weird. It hit in the 70s and is an actual avoidable problem. Don't kick the hornets nest. The issue of the Strait of Hormuz was known to nearly everyone for decades, and we got a bunch of leaders all over the West who are collectively batshit crazy.

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