/sci/ - Science & Math

I've responded to this bullshit post before. 41 kilowatts in an hour is impossible for a house. That number is in a day. Your math is totally wrong.

>>10708297
no it's 41kwh/day
my math is right

>>10708303
Okay in your own mind let us say you are right. Then why would you need
>41,000 * 1.2 * 1.2 = 59,040 w/h
of solar panels???

That makes zero sense.

>>10708307
I'll even clarify if you are that much of a brainlet. You are saying you need enough solar power that in one hour you have a days worth of power. The fucking sun shines more than one hour a day!!!

>>10708307
sorry that should be wh/day (I didn't make the retarded unit the power company did.).

You need to account for the inefficiency of the battery and inverter.
Assuming the batteries are only 80% efficent, you would need 20% more power from the solar array. Assuming the inverter is also only 80% efficent, you would need another 20% power from the solar array.

So let's just say it's a 60 kwh solar array

>>10708323
Lead acid is 80%. Tesla Lithium is 90%. Whatever. Just divide your end number by the sun you expect to get.

>>10708331
what do you mean?
Let's say I get 8 hours of sun.
Do you mean 60 kw/h/day * (8hours/24hours) = 20kw/h/day. Meaning I would need even more solar pannels to get to 40+kw/day?

>>10708347
You aren't funny at all.

>>10708357
i'm not trying to be. Come up with an accurate estimate for me and I will buy solar panels.

Given I pay $0.06 a kw/hour and require 41kw/hour/day, prove to me it's affordable.

>>10708269
My dad has solar panels. He doesn't have batteries or at least not 20k worth all for his own use like your example maybe a small one I dont know. The panels are connected to the energy company and everything that the panels generate that isn't immediately used is send back to the company. At the end of the year they subtract what is generated and sent back to them, from what he used from them (like during the night where the panels dont generate so the energy company supplies it). He says the panels generate about the same amount as he uses in a year.

>>10708269
>Why it's not joules idk.
This sentence is what marks you a retard. Stopped reading there.

>>10708373
Yes, that may be an affordable option on an individual level. I do not doubt that. The battery is definitely the most expensive part.

I want to make the point that your dad's setup is only possible because our electric grid runs off other sources of energy like nuclear.
I am very doubtful of those on /sci/ saying our electric grid should transfer completely to renewables. IMO i don't think it is possible.
If solar cannot even power a house, how can it power the entire grid?

The only downsides of doing that setup (from what I heard), is if the power goes out the city will disconnect your power AND your solar panels (so no additional current is flowing back into the system while people are working on it), so you will still have no power if the grid has no power. (I guess you could always hard connect something up in an emergency.

>>10708380
why? a watt is a rate. watt/hour is akin to a joule.
1 watt/hour =3600 joules.

watt != watt/hour

>>10708395
It's watt-hour. That's the industry standard, not watt/hour.
Joules / s * hour.
As in an appliance that runs on 1 kilowatt for 1 hour will cost you ~$0.25

>>10708269
>My house on average uses 41 kw/h of electricity per day
Pretty sure you mean kWh and not kw/h. So your house pulls ~2 kW. Cool.
>Let's assume...
Again, kW/h and W/h arent units that apply anywhere in this story. You need to pull 2 kW. So you need 2000 W*($0.20/W) = $400 dollars worth of solar panels. Jesus christ dude, you are off by a factor of 50 already. Not going to bother digging into the rest.

>>10708395
You're a retard because you think watts per hour are a thing and because you cant imagine the practical use of a watt*hour

>>10708409
>>10708410
>>10708419
ok. sorry I used kw/h instead of kwh. It's a pretty dumb notation imo. I don't even care about the solar thing anymore why the fuck isn't it just joules.

There are so many studies done which proved that nuclear energy didn't lead to cheaper energy.

The "low" energy price is more than offset by the subsidies and state guarantees - or the plain fact that they can operate without actually having any life-cycle plans for the uran used. There is not a single nuclear power plant in the world which could operate just based on the free market principle.

>>10708409
>Pretty sure you mean kWh and not kw/h.
>>10708409
>It's watt-hour. That's the industry standard, not watt/hour.

whats the distintion?

>>10708428
Because appliance companies use the unit of watt to describe how much power they draw. The average consumer doesn't think in terms of how many seconds they will run the appliance, they think in terms of how many hours. Hence the unit watt-hour is very convenient and makes more sense for our purpose. Kind of like how some machinery or trucks will record the number of "engine-hours" they are on.

>>10708439
Watts per hour =/= watts times hours

>>10708432
>There is not a single nuclear power plant in the world which could operate just based on the free market principle.
Is there a single energy source that does? Because all of them get gibs.

>>10708439
watt/hour would be akin to acceleration or increase in a rate over time. doesn't make sense in the context you used it. basically you don't know anything about electricity or power generation or basic physics and your opinion is worthless.

>>10708432
Well shit, guess we better just stick with the old stuff and poison the fucking world. Totally worth it just so the oligarchs can pocket a few more million

>>10708303
>41kwh/day
Christ, OP, wtf are you doing? My entire electric bill is $25-$45 per month depending on time of year. Your daily usage is like 2-3 times more than my monthly usage. I also pay more per kwh than you.

If I were to get a PV system it'd be without a battery array and be grid tied so that I'd use the grid at night or anytime the sun isn't showing enough. I'd only be using it for certain things, like PC, fridge, and grow lights/breeder lights. Though, those items are actually on their own UPS since the power goes out regularly for unknown amounts of time. Also, if I were to get a PV array, I'd make a few VAWTs to tie in to take up some of the slack. Those are really easy and cheap to make at least. If I lived in a place I could DIY up a sluice for hydro I'd do it in a heartbeat since it is also cheap and easy.

>>10708432
All utility power generation is heavily subsidized. Without it, you'd be paying dollar amounts per kwh instead of cents regardless of the type used. The subsidies come from taxpayer taxes of course so everyone is still paying through the nose for the power, even if you don't use any power at all. If subsidies were completely removed, people would still need power, but they'd be up in arms for a while until they realized why they need to pay $4-$10 per kwh or they'd just storm the plants and burn them to the ground and work as serfs for the biggest local Mad Max tier asshole. Mad Max scenario not with standing, it be better for everyone if power generation wasn't subsidized. There'd be a shit load more conservation and devices would be far more efficient than they are already.

>>10708432
Yeah, it's always funny how that nuclear energy is cheap argument breaks apart so easily.

>>10708432

OP mines bitcoin obviously.

>>10708495
So, who lined the pockets of the Royal Academy of Engineering to get nuclear down so far? lol

Why is this so complex?

Let us say my home was powered by 50 virgins a day. I have a solar panel that can make 2 virgins an hour. I don't need 25 panels because the sun shines for more than an hour a day. So if the sun shines for 8 hours a day, then I only need 3.125 panels a day, which make 6.25 virgins an hour or 50 virgins in 8 hours.

Battery and their losses is another subject. They use the cock unit, so you need more virgins.

>>10708532
>pic related: how many panels OP thinks he needs

>>10708572
This chart is too complex.

>>10708625
Get out of /sci/ then brainlet.

>>10708572
What is the percentage under each type of energy supposed to represent?

>>10708656
Note1

>>10708269
>41kw/h

41kwh x 365 days = 15000 kW/h per year

Thats quite a lot. 50% more than an average family home in the US consumes, 10,000 kW/h. So average family home uses ~28 kwh per day. 28kwh/7 hours of usable sunlight requires ~ 4kw solar panel.

We can buy a complete 4.7 kw offgrid solar panel set for $10K on solarwholesale with warranties/etc.

2x Tesla batteries is enough for it given each batteries gives ~ 13.5 kw per battery and can be bought for $13k.

Total cost is $23K if you do it yourself. $2000 more if you pay an electrician to install the system.

Now actual electricity usage average is 28 kwh per day x 10 cents per kw average in the US gives us $2.80 per day x 30.25 = $85 per month bill for an average home bill of electricity + $15 service fee + $10 taxes = $110 per month. $1320 for a year. Lets say you use the system for 10 years. That reduces the cost of system by $13K. In another 10 years, you're completely paid off. Now these things have 25-30 year warranties, so if those break, you can get new/better parts free. But if they last 10 more years, you save $13K. 20 years, $26K.

>>10708665
Lol I can't believe I missed that

>>10708705
>kW/h
Holy fuck stop saying this

ITT anon struggles with units and highschool math

>>10708485
Somewhat small city of ~40K here, $25 is just base tax/utility line usage.

>>10708572
I doubt that's not biased.

>>10708410
>400 for 2kW of solar
that's very generous. i assume you aren't including installation costs (if you aren't competent in bolting down some panels yourself lol), wiring, inverters, batteries, charge controllers, etc...
>>10708487
not the absolute cheapest- natural gas and coal are cheaper atm. it's the most VIABLE "green" (no air pollution, no water pollution) energy generator. INB4 muh nukler waist muh 4 gorillion year heff lief

>>10708740
Here that is $4/month if there's no usage.

>>10708776
He's getting partially broken cells off ebay and soldering them together himself, but he did that back in 2003 before everyone realized you could do that which jacked up the price of broken cells a great deal.

>>10708740
you're probably a coastal californian, new yorker, or in some other urban hellhole with high costs of living

>>10708787
Who? The OP?

>>10708781
>He's getting partially broken cells off ebay and soldering them together himself, but he did that back in 2003 before everyone realized you could do that which jacked up the price of broken cells a great deal.
There are 1kW panels on alibaba for $240. Like i said, panels aren't all in a solar setup.
>soldering broken cells together
I'd rather run on hot coals that do that. I'd probably vomit from the sheer tediousness of it.

>>10708790
>>10708740

>>10708747
so post a comparable study

>>10708787
Just the utility is high cost due to cost sharing being higher on ~40K population. Its not coastal California, but its coastal Pacific NW.

>>10708792
>alibaba
Which I shouldn't trust to be what the specs are.

>sheer tediousness of it.
It is actually very quick to do if you know anything about soldering. They aren't tiny or anything. It is like soldering together stuff that is the size of postcards or larger. If they have tabs on them then you can get up and running in about 30mins or so.

>>10708776
Google says about $3 per watt for an average installation so if you don't put it up yourself that would be $6000 before tax breaks. Keep in mind that the actual cost of the panels is less than a dollar and so you could save most of that money by installing a ground based system with angle iron and some concrete supports.

I'm pretty sure that anon was using the average cost of solar which is representative of large installations typically owned by power companies so he's still technically correct

>>10708815
I have a very shoddy soldering iron and shaky hands. Again, i would vomit.

>>10708849
It just takes practice.

If solar isn't worth it then why are there businesses that sell it for free while lowering your electric bill?

>>10708705
>>10708269
That's before any subsidies too. There's 30% tax credit for solar. So $25K or $34K becomes $17.5K or $24K. And that's for homeowners.

>>10708390
>The battery is definitely the most expensive part
You don't need a battery you fucking moron. Just send the electricity back to the grid. What's with this stupid obsession of powering your house/grid from only one source ? Solar is supposed to be a complementary power source.

>>10708910
Solar can be both complementary and primary power if you're offgrid.

>>10708925
going offgrid is a pointless luxury for everyone but crazy preppers so factoring it the cost of solar is stupid.

That and electricity production per square foot is absolutely ridiculous when compared to that of a nuclear plant

>>10708857
soldering porn

>>10708910
>send back to grid
they got rid of that iirc
>>10708931
You're retarded, going offgrid is perfectly valid for those with the know-how and/or money. I'd do it for the fun of it if I lived about 200 miles further south.

>>10708925
>if you're offgrid
I don't live in my van in the middle of buttfuck nowhere and I don't smoke meth on a daily basis so I'm fine.

>>10708931
>luxury
Wrong. Offgrid is for people who want to save money.

>>10708962
luxuries aren't inherently expensive, it's just that not everyone can have them. you can setup a security system for literally nothing if you know how to into electronicals

>>10708962
or you can just sell back excess power to the grid for credits so your power bill zeros out instead of paying 10k for a battery bank

>>10708968
This only works if the electricity jews allow you to.

>>10708968
That works if your initial net worth includes the expensive house. If your living in offgrid a cheap housing option + 2kw solar panel + 1 battery tank will last you a good 30 years. The entire setup minus the house/land would cost less than $3-5K.

>>10708986
Plus once global highspeed internet statellites become a thing in few years, offgrid solar housing should become much more due to reliability of the internet.

Solar panels and batteries degrade. In 20 years, half way before OP's return on investment. He would have to replace the panels and batteries. Since they would be to low performing.

If he has an EV then he needs to double his setup. So he can charge during the day or night.

>>10709030
Most of the solar panels guaranteed to ~1% loss of power per year. By year 29, if it exceeds more than that, you can get replacement unit.

Batteries degradation is a real thing, Tesla battery provides 10 year warranty. That's a good deal for batteries. Not sure of the details, but by 10 years, you would lose ~10% of the battery as well (if we go by their Tesla car battery analysis). So it should really be similar to the Solar Panel degredation loss of 1% per year.

>>10708410
Except those panels are only outputting their rated power for about 8 hours a day, so you need 3 times as many.

Also consider that peak total solar radiation energy to the earth's surface is 1300 watts per square meter. A good panel is 30% efficient. Making 390 watts per square meter.

60,000 watts needs 154 square meters of panels. About 7.5 standard parking spaces in a parking garage.

>>10708269
Solar panels aren't for poorfags or citydwellers. They're a backup power supply that doesn't create noise or fumes.

>>10709053
Actually I was bit wrong on the solar panel degredation. The ~$200/300 watt from Mission Solar has 20 year warranty and says panels lose less than 10% over 25 year period. That's quite a bit higher standard than I thought.

>>10709215
Yeah a panel that is 25 years old right now will have lost more than 30% but they have been getting much better.

https://www.youtube.com/watch?v=EahfGfDdgNY
is more efficient. and thats with current stirling engines and other not so efficient designs which could be improved. only thing holding them back is freakonomics and solar subsidies. PV relies on mining and more complex electronics manufacturing whereas stirling solar does not as much.

>>10708269
>your house consumes ~15,000 kWh per year (kw/h- really, dumbass?)
>a 1m^2 panel rated at ~150-200W (roughly a kWh a day) can maybe get 300-400kWh per year
>thus, 40-50 m^2 of panels are needed to break completely even (less if you live in sunnier parts of the world)
You don't need the powerwalls. You can transfer the electricity to the grid. You can also get such a level of paneling for like 10k if you do some DIY stuff- even with your cheapass electricity and including efficiency loss with age, those panels will break even after 13-14 years at most and you'll get free electricity for another ~10 years (at 70-60% efficiency) after that until they degrade completely.
The future is in the fusion-fission-solar trinity, pleb.

>>10709310
>all those moving parts
>10% capacity factor (as compared to ~15-20% (and rising) for photovoltaics)
That's gonna be a yikes from me.
That thing cannot be mass-produced or mass-maintained in any meaningful numbers, unlike the simple photovoltaic frames without any moving parts.

>>10708269
$0.06/kWh is extremely fucking low, even poorfag flyovers with rock bottom cost of living pay more than that

>>10709735
solar-wind-hydroelectric-nuclear you mean

>>10709876
Price of electricity doesn't depend on low cost of living. It depends on how much electricity your city/county/state produces and how much they can sell/export it to others.

People living near hydrodams will have cheaper electricity because they can sell it to other areas.

>>10709888
Average cost of electricity is still higher than $0.06/kWh for basically every state, and there is a correlation with COL and electricity prices.

>>10709801
dont need any moving parts in a thermoacoustic stirling engine.
if its about clean energy PV is dirty.

>>10711467
Lots of PV around. How many Stirling engines? Now ask how many thermoacoustic stirling engines?

>>10709310
>is more efficient
9000 kwh/year would need 40 sqm of PV (21% eff.) where I live. It's flat and you can install them on every rooftop in a city (ie unused surface).
That dish is a fuck huge volume and would be a pita to install and maintain in dense areas where you need power the most.

Solid state is the sensible way to go.

>>10709801
>thing cannot be mass-produced or mass-maintained
Said no one.

>>10711765
Vs Solid state solar panels.

PV is much cheaper/efficient vs Stirling simply because Stirling is a 2 step process.

>>10711761
the video says 17% efficient

>>10712763
The video is also from 10 years ago and PV has gotten a lot better since then.

>>10712786
>>10712763
18% is standard solar panel today. You can buy 375 watt panel for $200-$250 today.