Solar power
 

Mainly photo electric but thermal solar is alright too.

To get it started how about the myth of:
"A solar panel will never make more energy than it took to create it".
Fine, but I don't believe it. So a 220 watt panel could produce 1kwh per day for at least 20 years. That adds up to something like 7 megawatt hours. I dont think a little 220w panel takes any where near 7 megawatt hours.
My prediction is it takes way less than 1 mega watt hours.

I searched around some didn't find real clear guidance but I found something saying it take about 40kwh to make a 200 to 250 watt panel. That sounds pretty fantastic. I would like it to be true but find it hard to believe.

I found a 240w mono panel on ebay that measures 65x39 inches.

We will say worst case scenario no green washing. Panels made from all new materials.

The most energy intense part of the solar panel is probably the glass it's the bulk of the mass and energy intensive to produce. So start there. After looking around for a while I found some info on glass saying that it takes around 5 to 10 kwh per Kg of glass from new materials. Complex shapes take the most energy. Flat glass takes a lot less.
Even though a large portion of glass is recycled (more than a third) it all started as sand.

We will say the panel has 1/8 inch thick glass where I am you want at least eighth inch thick glass because of hail, and we want them to last 25 to 30 years right?. So 65 x 39 x 0.125 is 161 cubic inches or about 30lb or 13kg depending on if you self identify as imperial or metric.
The 240w panel on ebay weighs 42lb. I suspect most of its mass is glass. 30 of 42lb seems plausible.

So 13kg of flat glass lets say it takes 5kwh per kg. That's a lot more than 40kwh. But no where near 7Mwh.
Just the glass can we say it's 65kwh?

Next the aluminum frame.
Ok aluminum is insane I was way off when I thought the glass was the most energy intense part of the solar panel. 72 kwh per kg to make virgin aluminum.
Can someone help me figure out how much aluminum is in a typical 200 to 250 watt panel? I'm coming up empty.
I'm thinking its only 2 or 3 kg.

I haven't even tried to figure out how much it takes to make the cells. The process that makes mono cells is very weird and very energy intensive. Google it.

As far as gobbling up resources, solar definitely wins there.
https://ecomodder.com/forum/attachme...1&d=1682006578

Some analysis and adjacent stuff. I haven't read all.
https://www.quora.com/How-much-conve...-its-life-time

Off hand it wouldn't cost more energy to produce a panel than you could buy for the price of the panel. Though subsidies could play a part there are also profits, wages, taxes and equipment costs. Net energy needed should be less than the cost stands for.

Manufacturing $$$$$$$$$$$
 

I peeked over at GOOGLE and saw a number of solar societies and associations which may be able to provide some of this data.I'll look when I can.I'm very interested myself.
I suspect that the US Commerce Dept. also knows,to the penny,what manufacturers pay for facilities,administration,materials,labor,energy,c apital,fixed-costs,marketing, and each phase of fabrication etc..

That guy in NH is assuming an average amount of CO2 per unit of cost. That maybe gives you an idea of how much plant food is produced when building a panel. I want an actual number in KwH. The energy that made the aluminum portion of the panel is likely the biggest energy hog but aluminum smelting is usually done with very cheap nearly carbon free electricity most of the time. The glass portions energy is usually made with very cheap natural gas.
So the unit cost per CO2 only works with maybe like an entire industrial sector, not individual products.

I already figured out how much energy it takes to make glass and aluminum.
It's pretty easy to figure out precisely how much glass they use per panel. The Aluminum is more of a smash and weigh it kind of thing. Just need to know how much they use with out smashing one of my panels.

The exact unit cost is a trade secret in some manufacturing industries. One is tires, only the top 5 or 10 people in the company know exactly what it costs to make the tires.

For the cost of a panel I could buy around 1 mega watt hours of propane or like 6 mega watt hours of bagged high grade anthracite coal.
Problem is I don't have an efficient way to turn coal or propane into electricity.

My main motivations for solar panels are to actually be able to own some of my own power generation and profit.
Like all these people who bought into solar and are looking at like 9 to 20 year pay backs, haha suckers.
I'm looking at like a 2.5 to 4 year pay back. Used panels from AZ, constructing my own racking system, laying conduit, doing every bit of wiring that I'm allowed to do my self.
I would like to keep installing solar until it's no longer profitable.
I'm thinking that means up to a 12kw single phase 240v system.
Beyond that I would have to get my 3 phase 480v transformer hooked back up. Then I would be good for like another 50kw.

Alright I found extrusion specs for a 130mph rated panel frame.
The thin cross section is equal to a 100x1mm flat aluminum strip and a second heavier part would make a 13.6x2mm flat bit.
So the cross section is 127 square mm. That would be like a solid 11.2mm square rod running around the panel, just to give you an idea what that aluminum would look like all compacted together.

So a 250 watt panel would have about 6 liner meters of edges to protect.
That's 762 cc of aluminum.
The density of aluminum is 2.7 g/cm.
That equals 2,050g.
I believe I said that I thought a 250w panel had 2 to 3 kg of aluminum in the frame.

So let's say a 250w panel has a frame weighing 2kg.

Now we can say a 250 watt panel takes about 300kwh to make the glass and aluminum. I still think that's pretty good and is no where near what the panel will make over its life time.

That leaves the solar cells. It looks like mono are very energy intensive but CdTe thin film use a lot less energy to make.
Apparently thin film is where it's at for utility installs, residential installs tend to use mono.

I have almost unlimited space so I don't have to use high $ mono when I install panels.

I've read a bit about this issue. Generally the non-return on energy is just another fossil fuel ruse to try to keep people from buying solar. From what I can gather there was a time when it may have cost nearly as much energy to build a panel or module as it ever returned. However in the last ten years with the increase in panel efficiencies, improved manufacturing methods and higher volume the energy costs have decreased dramatically.
Here's a link to more recent data that suggests an energy payback of one to four years.

https://solarcraft.com/solar-energy-myths-facts/

https://fjmy22wdc4e32bv93fwuolvh-wpe...4/cumenerg.gif

The graph is on that page too.

JJ

One further consideration to keep in mind 2-3 decades down the road, can solar panels (and giant wind turbines) be mined, refined, manufactured, and installed, without fossil fuels? Which they are currently completely reliant on every step of the way.

The amount of energy that it takes to make glass and aluminum hasn't changed much. That part of the solar panel isn't going to change, where you are basically making an aluminum framed window that doesn't open.
It doesn't appear that solar panels will beget solar panels aany time in the foreseeable future and when they do it sure as heck will cost a lot more than one fiat greenback per watt.

Several years ago I volunteered with a nonprofit in Los Angeles that installed solar panels on low-income homeowners' roofs. It was part of a state project in distributed solar power generation. I worked on three or four installs, most of them single day some of them today projects.

It seemed to me as if the primary costs, in retail terms not ROI calculations, were the labor and extra fees that install companies add on to the costs for their own profit. The install itself is not very complicated: anchoring the rails for mounting the panels properly and securing the panels and inverter modules to the rails. Both grounding and wiring was taken care easily through Plug and Play Type connectors. It somewhat more complicated and a bit more necessary to get a professional electrician once you want a tie into the grid. The overall simplicity of the install was improving during the two summers and which I volunteered. it's possible that it's even simpler now.

It's just not that hard. Your expectation of a return on investment within a handful of years seems entirely reasonable given that you're going to do almost all the work yourself, especially if you are buying second-hand panels.

Why a 50 kilowatt hour setup? I mean, one way to drive up your costs would certainly be to overbuild and therefore buy too much hardware that you don't really need. I would imagine 50 kwh is maybe because of the electric vehicles you're planning?

The local electric coop limits residential peak grid feed back to about 12kw. I can install more than 12kw of panels if some face east and west but I would rather not.
To install more capacity I would have to go with a 480v setup. No one has done this on the coop so there is no president. So I have no idea how much it would cost. If they hook the transformers back up and don't charge any money good, because I already have a 480v 3 phase transformers on a pole and wires ran to a pump house at aren't being used.

But when I drop down to getting paid generation rate the pay back goes out to at least 10 years. I would probably have to put them on single axis trackers.
I sent my single axis tracker design to my mechanical engineer and he says it looks good, too over built in his opinion. But the trackers are designed to survive a tornado. The panels will be shredded, just add new panels.

For just the glass and aluminum we are looking at about a year worth of energy.
I could believe a 1 year pay back if it's CdTe cell panels since they take almost no energy to make compared to mono.
But all i can find is abstract not actual numbers.
[4 to 5 energy units of CdTe equal 1 energy unit of mono]

Found this paper which appears to be a study of studies of Energy Payback Time for energy used of various PV materials. It's only four years old, so fairly recent.

http://astro1.panet.utoledo.edu/~rel...nergy_revs.pdf

The chart on the fifth page shows the energy cost for the various materials. Later, payback times are shown. Their conclusions are about the same as in my earlier post of about a one to four year payback depending on the material used. Dozens of references are given if anyone would like to dig deeper.

JJ

So it just occurred to me that there are different ways to look at those numbers. On first blush a payback of even the larger number of 4 years seems like a good deal on a solar panel with a 20 year service life. But when viewed in the terms we have always used in assessing fossil fuel extraction, which is ER/EI, a value of 5:1 would be considered economically very marginal.
.
But whatever solar and wind and electrification of all systems that we can get built in the next 30 years will be much better than nothing and will be a big help in extending whatever liquid fuel we have left after that.

I agree with sendler's general idea that we need to transition away from dwindling resources prior to "running out", but I foresee a more gradual letdown in resources. After all, we saw what happens when fuel prices are very high; we start cranking out the fracking sources domestically.

So it will go, as scarcity sets in, the more difficult to produce sources of fuel will be tapped. This will cause a gradual rise in prices that will spur further incentive to utilize alternative means of energy. It's not like 40 years of abundance and then the light switch is flipped off.

I would rather have cheap steel, cheap concrete, cheapish aluminum, roads and bridges ect. for the rest of my life then drive a 10mpg pickup around for 10 or 20 more years.

Being involved in electronics and engineering for many years now I have become somewhat proficient(lucky) at projecting(guessing) timelines for new or better technology. I was able to guess about when compact disks would come around from working in computer manufacturing. When I started we were still working with 8 inch floppies.
As soon as the television people started talking about hi def digital televisions I knew it wouldn't be long afterwards that they would basically become computers.
From what I see, the break even economic cost of solar is already here as long as you stay connected to the grid. You just have to get the power companies on board. Will they like giving up all the income and control? Almost certainly not. But if they want to stay in business they will have to do just that...or buy more politicians.

And as we have already seen, the energy return has already long surpassed the break even point. Still, that part is based on at least six year old technology. I am going to guess that within ten years even residential solar modules will reach 28 to 30% efficiency using the new technologies that are now being developed. This should give almost every module an EROEI of less than a year. It also should lower the dollar cost per watt even more. Will everyone want to switch over? Of course not. I've actually had friends tell me they wouldn't have solar panels or drive an electric vehicle even if they were given one. Some just don't understand the increased efficiency of an electric vehicle. Some are afraid of newer technologies. Some are the type that won't change because it would require them to admit they were wrong about solar and electric cars.

The thing is that even though both the concepts and physical devices of solar power and electric cars have been around for many decades, they are both still in their infancy on the technological timeline. If either of those two had as much research put into them as ICE vehicles have, there would no longer be ICE vehicles except for specialized uses.

JJ

A kid in high school told me he was building a home network, and I said that was dumb and pointless. Then 10 years later everyone had wireless networks.

Internet on phones was a novelty for wealthy folk, I said.

Finally, when SSD storage hit the market, I was done being pessimistic about adoption of technology and experienced firsthand how superior it was. Based on my experience, I figured 2 years and it would become the dominant storage platform. It's been about a decade now and were not quite to the 50% mark yet. It was adopted much slower than I had anticipated.

Location and utility costs have as much to do with solar adoption as the cost of the panels themselves. Half the days in the valley here are overcast or rainy. The sun is never directly overhead even in the summer, and the utility rates are among the lowest in the nation. There's absolutely no reason for me to install PV here. If I wanted to install PV, I'd install it in someone else's house in AZ and have them send me a check for the monthly production.

Raid drives are expensive as all get out when done in silicon. Probably no reason to do them either. 8 or more terabytes done on platter storage is reasonably cheap.

I'm just surprised it's still cheaper to build precision mechanical devices that spin at 10,000 RPM to store data than to just print 'em on silicon. I wonder when there will be price parity?

I saw a 8 TB drive for $130 the other day. The cheapest SSD I can find is 1 TB for $94, so still 5x more expensive. My programming teacher in high school said the largest database in the world was owned by Walmart, and it was something like a terabyte in size. He said one day we would have 1 TB drives in our computers. At the time he said this, top of the line computers had 1 GB drives and 100 MHz CPUs.

There are also frame less modules out on the market which means essentially no aluminum needed. I'm only going to cite one example and that is the Lumos LSX system.
In its spec sheets the overall weight of a 280 to 290 watt panel is 62 pounds. Glass is on both sides of the panel so I'm going to guess that at least 50 of those pounds are glass. So let's call it 23 kilos.
Using Oilpan's energy usage numbers for flat glass of 5kwh per kilo that gives 115 kwh for a 280 to 290 watt panel not including the energy cost of the cells themselves. So that's an energy cost saving of 300 - 115 kwh or 185 kwh per panel. Seems pretty substantial.
Here's a link to the spec sheet.

https://lumossolar.com/wp-content/up...et-6252018.pdf

Here are a few other thoughts on newer types of panels.

https://news.energysage.com/new-sola...2018/#comments

JJ

It says the frameless panels lack a suitable mounting system.

Also some utilities are anti solar. Where I am excel energy has made it so you have to jump through every hoop imaginable.
Plus electricity is cheap here.
I'm on a coop now. Their solar requirements are minimal.

down the road
 

I'm gonna say yes,only because there's an imperative that it be so.
And if the necessity of invention is a mutha,and necessity is the mother of invention,then those with a passion for solving this issue will emerge from the woodwork,and apply all their skill sets in the intervening years.It's what Americans do.And our global neighbors.

ie mining, transportation, construction, agriculture.

Mining: Electrics have been in use underground for decades to keep underground gasses from igniting. Battery powered electrics are just coming into their own.

From Medatec:https://medatech.ca/case-study/batte...-mining-truck/

"Why Electric

Battery Electric Equipment allows a mine to unlock a trifecta of benefits: improved health and safety, reduced greenhouse gas emissions, and decreased operating costs. Removing emissions from even a few metres, never mind kilometres, below the ground requires massive ventilation infrastructure—shafts, equipment, and enormous amounts of electricity to run the machinery.

“Moving away from diesel and by achieving other reductions associated with the use of clean technologies, (a typical mine) can avoid more than 7,500 tons of CO2 and eliminate 3 million litres of diesel fuel, 1 million litres of propane and 35,000 megawatt hours of electricity every year.”"

Transportation: Well, train engines have been hybrids since the beginning of diesel engines. The diesel powers generators for the electricity and the electric motors move the engine. Can they install enough batteries to take the place of the diesel engine? Don't know. But I bet if they can figure out a way to do it, say maybe add a battery pack car, that they will because a ninety percent battery pack efficiency is better than a thirty percent efficient diesel engine.

Flying might be a more difficult challenge but many there are many groups around the world working on it right now.

Construction and Agriculture: Guess it depends on the type and location. In the past I've used both ICE powered and battery powered lifts in construction. Never did any farming although I grew up in the land of corn and beans.

The point is, I'm not suggesting that every piece of fossil fueled machinery will be eliminated but that a huge amount of them can be and likely will. There are always exceptions to every rule and that's fine. But if something that is logical and somehow makes the world a better place can be done, then it should be done.

JJ

Please do the math regarding how much battery capacity it would take to move a train any reasonable distance. Or heavy truck. or a large farm tractor. or an earth mover that carries a load uphill. There is no replacing the nearly magical energy density of liquid fuel that we are now blessed with for doing heavy work.
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https://scontent-lga3-1.xx.fbcdn.net...0b&oe=5D4790FB
.
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570 Liters of diesel per day = 5,700 kWh per day. Even if you cut that by2.5 for the extra efficiency of electric motors with round trip losses you get 2,300 kWh per day for a large size farm machine. 12 Tesla grid scale 200kWh powerpacks per day to hot swap in and out. for just one tractor. We are going to need to start making a lot of wire to get all of this power around

Thr big diesel locomotives have something to the tune of 6,000hp and carry 5,000 gallons of fuel.
They could be powered electrically with external power.
It would be difficult to replace the 5,000 gallon diesel battery.

:)

https://duckduckgo.com/?q=roll-to-roll+film+solar

https://duckduckgo.com/?q=tesla+roof

Keep these in mind when doing projections.

CAT LEXION
 

I took the fuel consumption of the harvester,converted to gallons,then to Btus,then kWhs,then using 44.2% thermal efficiency,ended up with 2,696.696 kWh/day.
If the farmer broke their work day into half-days,we'd be looking at 1,348.3 kWh at a stretch,between meals on a long day.
It might be possible for the rear wheels to be the batteries,containing enough battery mass for a half-day's work,then fast-recharge the rig during 'lunch'/'dinner'.
Typically,these tires are filled with water,are extremely heavy,and might as well serve double-duty,rather than just as dead weight.
If rationalized,as a standard dimension,they could be used across all manufacturers product lines,fitting all brands.

By the time combines go electric, they will have been full auto well before that. You'd have a controller in charge of 10 combines remotely monitoring operations, with the harvesters operating at 99% autonomous.

It matters less how long to recharge if the harvesters otherwise don't take breaks and work 24/7 around the clock. Then again, simply refueling and moving on to the next field makes it much more appealing to large operations.

Perhaps tractors are the correct operation to utilize quick swap batteries. Use one while the other charges.

Maybe then the battery would only need to be ~400 kWh, or large enough to handle whatever the continuous load is without being damaged.

What is the typical HP demands of a combine?

horsepower
 

The CAT LEXION 500-series was listed at 462-hp.

It would just need a 1 mega watt charger to charge up during lunch.
A 1.5 megawatt hour battery would only weigh 400 thousand kilograms and cost around a half million dollars lol.
(If 1 Kg of lithium ion batteries can hold 0.265kwh and $1 buys 3.6 watt hours)
Farming machinery is probably going to continue to be liquid fuel powered.
Then some of these machines only get used for a few weeks a year.
Some machines only stop when they put fuel in them and when they get trucked down the road to the next field.
They have to run nearly 24 hours a day or the crops rot in the field.

That's continuous duty?

Doable with a 400 kWh battery at a 1C discharge rate.

Swap packs with a freshly charged one and throw the drained one on a 1C charge, which some DCFC are just about capable of.

100% duty cycle?
 

Sorry,I don't know.They might run them at 80% like an aircraft or car,but I'd just be telling a story.
We could use a bunch of veterans/experts here at EcoModder.:p

Very rough estimate based on forums...

The max rate I read was 19 gallons per hour. Many reported around 5 gallons per hour.

19 gallons x 7 lbs per gallong is 133 lbs per hour.

Given a reference to 0.5 lbs of fuel per horsepower hour, that works out to 266 horsepower.

That works out to roughly 200 kW (266 horsepower x 746 watts).

So a 400 kWh battery would give a combine in worst case useage 2hrs of runtime. Swap the pack out with the one that has been charging and you're good to go again.

Heck, you might even be able to get down to 200 kWh or so for about an hour of hard use. That's not too shabby. The only downtime would be the amount of time needed to swap packs.

OK. I'm just using a Tesla 85 kwh pack as a reference here. Assuming we could just tie a bunch of Tesla packs together. Check my math for me though.

An 85 kwh pack weighs 540 kg.
1.5 Mwh = 1500 kwh
1500 kwh /85 kwh =17.65 Tesla packs
17.65 x 540 kg =9531 kg.

Current cost of a Tesla pack is $111/kwh. I know that even if we could get them that would not be our cost. But.
$111 x 1500 = $166,500.

See anything wrong with my numbers?
JJ

Numbers look good to me. As I stated, I don't think the goal will be to run 12hr days on a pack, but rather switch them out since such a large pack is expensive.

Oops decibel point in the wrong place. I thought that seemed heavy.
Tesla sure has made their batteries cheap.

Ethanol would be a much better choice to replace diesel in Agriculture.

Trains run on a fixed track. The obvious solution is overhead electric as used on most modern passenger trains.

That's what I ment by .