Solar, Wind and Battery Power Discussion

Communities Science, Engineering, & Security
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Hi all, and welcome. This thread is about discussing the Solar + Wind + Batteries grid takeover that is going to take place during the 2020s decade. Tangential to this is the unfortunate demise of base load (yes, even nuclear - it just doesn’t fit the new puzzle but is in all other ways a great technology), small scale electricity generation in the home / community, and the takeover of the electric car.

This is a long, complex, and fascinating topic that have many moving parts. The TL;DR is that by 2035 (some say as early as 2030), over 50% of all electricity generation will be renewable. There is a lot of misinformation and screaming online to try to slow this down. In my opinion, you might as well scream at a tsunami coming for your house at this point, it is now as inevitable as the shift from horses to cars was in the 1910s. This post here is to try and help sort out some of the cognitive dissonance a lot of people still have on this topic, while the thread is for discussing the technologies involved.

Let it begin.

The backbone of electricity will be SWB

Summary - Solar, Wind and Batteries (SWB) will dominate the grid in the future. That is not to say SWB will make all generation, just something like 80%-90% of it. All inherent problems with the technology are now solved, but yet to be implemented everywhere - That is what the next 10 years are for. There are a number of challenges left, but none that pose any impossible hurdles, just blood, sweat, and tears of technology that already exists.

There are two key reasons why SWB is inevitable, and both have to do with economics. The first is that an SWB grid is now the cheapest option to install, operate and deliver power with, by far. The second is that an SWB grid will disrupt base load power, forcing it to operate at only certain times of the year. There are many other reasons why this is desirable, not the least due to a certain global crisis that has been around since the 80s, but these two reasons are why it will happen within a decade.

The SWB grid is inevitable - Cost

The economists Tony Seba and Adam Dorr have already made an excellent report published by the RethinkX think tank. If you are not familiar with Sebas work, he is the guy that predicted the fall of oil by 2030… In 2013. So far, his prediction has proven to be a bit on the pessimistic side, because latest measurements are ahead of the prediction by six to twelve months.

In November 2020, Dorr & Seba released an extremely controversial report that details exactly what is happening here. I recommend anyone still in doubt to watch the below presentation video of the report, where the case for the SWB future is made. The report is free to download on the RethinkX webpage: Rethinking Energy 2020-2030 (2020) (English)

Apart from that, I would just like to share with you the latest known economic numbers for LCOE, which is a way to calculate Return of Investment on a power plant. LCOE is not a perfect measurement by any means, it leaves out a few key details and SWB is a bit more complex, and methodologies can and will differ. Still, the Lazard Institute produces this report every year: Levelized Cost of Energy+ | Lazard

And in the 2024 version, you can easily find this graph:

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Which just shows that Solar and Wind power is the cheapest power, and the reason it isn’t declining further right now, is because batteries are slowly entering the mix. Finally, it seems their prediction of S-curve disruption is coming true (thanks @level1):

image

SWB will not grow forever, and this graph is for solar alone. Wind and Batteries are following a similar trajectory, however. Now, cost is not everything, but for new grids (or smaller grids) like those in developing countries like Africa, SWB is cheap, resilient and affordable.

The SWB grid is inevitable - Base load competition

The second reason why SWB is taking over, is that it is not adding to base load - it is a replacement to base load. Again, Dorr & Seba has an amazing take on this from 2021, and I recommend everyone to at least watch the video presentation of that report, but here is the actual report: Rethinking Energy 2020-2030 (2020) (English)

The basic gist of the argument, is that as more intermittent power is added, cheap intermittent power will force base load plants offline for certain periods of the day in order to keep the cost of producing electricity down. If you are burning coal or nuclear for $100 / MWh and SWB produce the same kWh for $50 / MWh, it makes more sense producing SWB as that gives more profit per MWh (electricity price is unchanged).

However, if you have to shut down base load for 8 hours a day, your LCOE equation is thrown off - all of a sudden that coal plant will produce for $125 instead of $100. Which means even more incentive to do SWB. Which means base load is now shut down 10 hours a day. And on and on it goes.

This is unfortunately the reason all current Base Load power generation is going to be stranded assets as SWB increase their injection in the mix. Who in their right mind would keep a base load plant running if it only produces profitable power 5%-10% of the year?

And if you think incumbents won’t let that happen, they will have no choice as capital flock to new, hip startups that can provide intermittent power for half the going rate. The laws of economics guarantee base load demise, and the shift will happen sooner than most people realize.

Building a resilient SWB grid

[To be Written, how the SWB grid is supposed to work and can be made even more resilient than base load grids]

The future is looking bright

I hope the above gave some clarity why I, and many other experts, now believe that SWB grids are the future. It may sound like sunshine and rainbows, but actually it isn’t. Can we do this? Yes, without a doubt. Should we? That is an excellent question that unfortunately doesn’t really matter anymore, the world is going SWB no matter what anyone think, it is by far too late to stop it now.

In the post above, I have tried to focus on the fundamentals on a very complex and wide topic. I could easily write over three thousand pages on the subject, spanning multiple books. If I did, I fear many would fall asleep before the end of the first chapter. So, there is a lot of nuance left out for now. I hope the thread will pick up many of the nuances missed.

Disclaimer - Post is still a WIP, please bear with me as I attempt to juggle my personal life with writing this piece :slight_smile:

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I have been wanting to get it done on our house. No batteries just roll back the meter since batteries are expensive and would need more maintenance. Maybe later on a few smaller ones for power outages however.

My wife’s brother has them installed on a rotators to make sure maximum sun is achieved. He doesn’t pay a electric bill anymore but where he is; he gets sun a lot of the time.

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Global electricity consumption in 2023 was 29,925 TWh
That’s 2.9925×10¹³ kWh/year
There are 8766 hours in a year
Humanity therefore consumed 3.414×10⁹ kW

Earth has a radius of 6,371km
Its cross-sectional (‘always noon and summer’) area is therefore 1.275×10¹⁴ m²
It thus absorbs 1.275×10¹⁴ kW of solar energy
If we ignore the 70% that falls into the ocean
3.825×10¹³ kW falls on land

We therefore need to harvest
3.414×10⁹ ÷ 3.825×10¹³ = 0.00008924 = 0.008924%
of the solar energy that makes landfall

If we go with your own 120W/m² nett capture figure…

Covering a mere 0.07436% of land with solar panels would meet ALL of humanity’s electricity needs.

Basic calculations — that even primary-school children are able to perform — thus confirm that solar can easily be the electricity supply “backbone” for our entire planet with the current 8 billion people, or even 80 billion people, without even breaking a sweat. And since all of that land can be dual-use (e.g. with agriculture), no other industry needs to suffer.

tl;dr: Generation density is utterly meaningless because… math.

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Software With Benefits?

not if I ask CoPilot…

and what can I do to help?
Donate GPU time?

yeah, how’s your solar farm work during nuclear winter?
or after muh climate change blacks out the sun from all the carbon emissions?

zoom out…

bell-curve
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I for one believe we should deploy solar farms over all of New York, California, Seattle, Chicago, Portland, Atlanta, Connecticut… actually all of the blue on this map:

2020_United_States_presidential_election_results_map_by_county
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But the reality is: Solar is not (yet) efficient

And if climate change is your concern, what effect do you think square miles of black will do?

But I can’t buy a gas powered Porsche after 2030?

You are describing a fantastic solution for space based energy capture, but honestly we have so much potential energy here that is far cheaper. We should be advancing towards the stars instead of preserving a world for Communist countries to inherit.

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Without efficient energy storage, this is all for naught.

People use power when they go home from work, energy consumption is non linear. Unless you planned on switching everyone’s work hours?

Look at hydroelectric batteries. Then realize your plan comes with caveats.

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I see an opportunity for me to rant. I’m unable to do a solar setup for myself yet, but maybe next year. I’m planning an off-grid setup, so I’ll need battery power.

Over time, I’ve been fairly for 12V systems and mostly against 24V and 48V systems. I’ve kinda started gaining a new respect for 48V systems, because you can easily store more energy in 48V batteries and you need 1/4 the wire thickness than a high-amp 12v system. Even if you need a step-down converter for most stuff, 48v has just too many advantages (alongside less voltage drop over a longer run). The biggest advantage is its ability to easily convert to AC (because you don’t need a lot of current).

Because of my insane ideas, I want to set things up separately, so that important things, like my fridge and router will never run out of power. I’m thinking of a split-system approach, with maybe 2 panels in parallel for a 12v system and 4-8 panels in series or series + parallel for 48v.

Unlike 24v, a 48v system will spark and can definitely kill you. With a 24v you can still touch exposed terminals, it’ll give you a small shock, but you won’t die from it. Everything over 30v is kinda dangerous, so with a 48v system, you need to prepare a bit and make sure there’s nothing exposed.

Stepdown converters are fairly cheap, although the 48v ones are slightly more expensive, but if you plan on having some high-powered AC appliances, then it’s kind of a no-brainer to go 48v. While I wish I could do everything on DC, I don’t think that’s feasible.

I’ve already made a lot of preparations already, by making myself a few 12v cigarette socket boxes with dedicated switches for each (I’m literally running my low-powered PCs and my lights in my room on 12v right now, although with AC bricks). My UPS is actually happier. With each device having its own AC brick, my reported power consumption was higher. I dropped anywhere between 20 to 60W by going with larger DC PSUs to power everything (120W bricks).

One thing that’s really fascinating about a solar future, is how work-hours would be affected. I’m really glad someone on the forum shared the site Low Tech Magazine.

The whole website is literally an exercise in “solar power” (not sure how to even put it into words). The site is powered by an Olinuxino A20 Lime 2 SBC, a 40W solar panel and a lead-acid battery. The site goes offline when there’s a prolonged absence of sun.

The author lives in an apartment in Barcelona (so they’re getting sun a lot more than people in the north), but instead of trying to oversize the setup for a meager random site, the site was made “sustainable” by deciding to limit uptime. The site doesn’t need to run 24/7 and it’s something we as a society have been really accustomed to.

Even the grid is running in such a way that you’re incentivized to use more electricity at night than during the day (if you have an off-peak plan and a meter that knows how to tax you during certain hours). Most people operate during the day, it’s kinda our nature. But with cheaper electricity at night and the advancement of technology, we started getting things like 24/7 stores and gas stations, night clubs, brightly lit streets (literal light pollution) and more.

When you think about solar, particularly the off-grid type, you’re obviously thinking about using as much power as you can during the day. Turn on your AC, your dishwasher, your oven and more. You can’t store all that incoming power in batteries. At night, when there’s no sun, you lower your consumption: switch the AC with just a fan (if nights are cooler than your conditioned air), don’t use your dishwasher, turn off your high-powered servers and so on.

In a solar-powered world, we’d see a reverse in most of the night-time changes during the past century. Sure, batteries are getting cheaper and more sustainable (sodium batteries anyone?), but we won’t be able to satisfy all the households to run their AC’s at full blast on 68F / 20C. Similarly, not all business will want to operate at night, when electricity is either going to be more expensive, or when they need to operate on battery power.

Sure, there will be some businesses that will charge customers a premium to operate at night. In some countries, some 24/7 stores are using 2 prices on the same items. If you buy stuff before, say 10 PM, you get it at the standard rate. If you buy things after 10 PM, you pay more (I heard something like 50% more in some cases, that’s insane if true).

The dynamics of the world would change drastically. It might not be as cheap anymore to hire people to work in a call center after 6-7 PM, if you need to power your building with a generator, or if the grid supplies power at higher rates at night (with maybe a combination between wind and natural gas generators - gas generators are the easiest to spin up and down when there’s high fluctuations in the grid, they’re a great add-on on a solar and wind generators if you want consistent, non-fluctuating current, i.e. if you don’t want brownouts or full out blackouts).

Of course, some businesses, like stores and anything that involves refrigeration can’t just turn off the power, a lot of food would spoil. So these, if they’re still on the grid, will have to pay the premium for power at night, but save money in other ways, like turn off the lights and make better, insulated fridges, so they don’t lose all that cold air to the air around the room. Instead of large fridges with glass doors, we would see fridges insulated in foam, with maybe cameras and lights inside and huge TVs on the outside, showing you what’s inside. With the solar power generated during the day, all the lights and TVs can just be powered on. At night these get shut off, while the fridge part keeps running.

Websites and datacenters too. We might not be able to see many websites operate at night anymore, because electricity would be expensive. Just like Low ← Tech Magazine, some sites might just go offline at night, unless they’re operated by people who will oversize their battery setup to insure more uptime.

Speaking of uptime, even SLAs for datacenters might change. Premium DCs will have connections to the grid, being powered by coal and maybe nuclear here and there (this week Wendell mentioned something on the L1 Show about Microsoft buying the 3 mile island), with maybe generators sitting nearby in case things go south with the grid.

Cheaper DCs will offer customers “daylight plans” only, with hardware being more consumerish and hacky, obviously having terrible uptime contracts (eventually people might get tired and take things into their own hands and have better uptime in their own house with small batteries and low-powered computers).

I can imagine such a solarpunk future. I don’t think it’ll necessary be the utopia that some people think it would be, but I have big biases against over-consumerism and people staring at their phones or computers for long hours doing nothing. While not a utopia, it wouldn’t be too bad of a place to live in. Most industries aren’t 24/7 operations and not all businesses should be operated on a just-in-time plan (look how well that went during the coughy-coughs period).

Imagine during periods of intense rains, or simply cloudy (non-rainy) days, people would just get time off of work, because there’s not enough energy production to meet the demand. Not every workplace would have such a great opportunity for random off-time, but some would.

While I can envision something like that for sustainability, I doubt most people would want to return to a simpler lifestyle. I suspect new ways to store energy would come into play. For example, either Low Tech Magazine or its sister site No Tech Magazine had an article about a compressed air fridge, where someone made use of a large compressed air tank outside the home, compressing air and letting the tank cool, then decompressing air, making a cool tank and sending that cold air in a fridge. There’s also whole shops that only use compressed air for their power-tools, so steel tanks and air, with pumps could be a cheap storage of energy.

Something like that, but in large quantities, or maybe things like putting trains on a mountain during the day using solar and letting them go down at night, using gravity, to generate power could be another storage of energy. Pumping water to a higher elevation, then dropping it to make a hydro-electric plant would also be a smart way of storing energy, without the usage of batteries at all.

So there’s solution to power at night, but they’ll still be slightly more expensive than just solar power alone. Compared to today, there’s definitely going to be a shift into more daylight activities.

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For off-grid deployments solar is fine

Grab the biggest UPS being surplused and use that

I’ve owned up to 80kva UPS that use 48 12 volt batteries
If I remember correctly, it was wired 6 series of 4 parallel banks
Wire up each panel to each bank as the voltage difference within each bank is still 12volts nominal and enjoy.

You’ll have a ridiculously efficient and cost effective inverter

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Anything less than 120V DC is classified as Extra Low Voltage (ELV). It is safe-enough for amateurs to play with so most western jurisdictions don’t even bother to regulate it.

Although shorts can be startling and impressive, DC injuries tend to simply be burns. Your heart doesn’t stop, you just cook some skin/flesh and then need to put some cream over the burn site and/or cover it with a bandage.

It’s AC that stops hearts. Ventricular Fibrillation can be induced into the heart with as little as 120V AC and about 115mA of current. That’s what kills folks. And that’s why the ELV standard only includes AC up to 50V.

tl;dr: Standards define ≤120V DC and ≤50V AC as Extra Low Voltage and low risk. Exercise prudence and caution with such systems, naturally, but there is no need to be overly concerned or paranoid.

PS: The currents that flow during shorts or electric shocks are usually significantly limited by the DC source’s internal resistance. The special case of capacitors is worth mentioning. They have a very, very, very low internal resistance. As a result, they can produce very, very high currents when discharged. Regardless of the voltage, take extra care when dealing with capacitors — especially the high-capacity “supercapacitors”. Grab a fully-charged supercapacitor the wrong way with a sweaty hand and you can blow off a finger.

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I don’t see why SLA batteries aren’t more popular in whole-home solar. They’re pretty dirt cheap, and heavy; but it’s not like the ground can’t handle it. Their energy density is about half that of Lithium-based chemistries, so maybe they’re more expensive per Wh of storage. I haven’t looked into it yet, but if I were to try going off-grid with whole-hone solar right now, I’d strongly consider Deep-cycle SLA batteries. And Deep-cycle Gel SLA batteries are used in Golf carts and Mobility scooters so they have economies of scale on their side compared to regular deep-cycle batteries.

Oh yeah, lead-acid batteries can take the heat a little better than lithium ones.

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Isnt this kind of useless data like a 350w panel in Canada is not going to generate the same power as in like Texas. So “installed watts” doesnt mean shit (not to mention way its facing etc)

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That is pretty good math estimation really. On the low side, even with your choosing “optimistic” predictions though. The panels on my house put out around 300-320w at noon in the summer, each (and at winter solstice with lowest light per day around 200-210w each). A single panel is more than a sq. meter though, They are closer to 1.4 sq meters which comes out to 215 watts per sq meter.
My daily kW output in summer at peak from around 11am-1pm is 12kw, with tapering off from there as you go earlier or later in the day. In winter for the same time it peaks around 8.5kw. These numbers are enough to run my home just fine, and if every house, apartment complex, etc had the roof covered in panels then it would easily power everything. The main part then is just storage to keep it all to ride out from evening till the next morning. But since the homeowners typically own the panels, at that point Utilities could just be in charge of most of the grid storage to keep it running and maintaining the lines, and get their payments from those two tasks.

I am really excited for the testing going on with just that, space based solar energy farms. Since energy is really just frequencies and wavelengths they just have to convert from one form into another efficiently. The testing is generating electricity from the light energy of the sun (the obvious part), then convert that electrical energy either back into light in the form of lasers or convert it into micro waves, then beam it to earth on a tight beam, high power transmission. A ground based station has a receiver dish that either absorbs as much of the micro waves as possible or uses solar panels here on earth to capture the extremely high energy density lasers, then converts it again back into electrical energy to use. Lots of conversions sure, and hopefully we can make all the steps of that more efficient. The benefits though are 100% uptime of the panels making electricity, so no storage needed, and the energy density is far higher so we make way more power. You can also send the power to many different places on the planet instead of just one spot, so you can have 1 massive station up in space beaming to a dozen different cities on earth. Same goes for military operations, being able to have mobile power plants that receive space based power that can move with troops and bases.

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That’s the way the whole world counts everything. Car sales do not take into consideration the fact that the average car is only driven 3% of the time. Hammer sales aren’t devalued by 99.99% due to them hanging idle on a hook or sitting in a toolbox. You don’t get a refund from the water company if you don’t drink all of the water coming out of your tap. Under-utilisation affects everything.

It is neither logical nor ethical to single-out solar and attempt to invalidate the hard data on the basis of under-utilisation.

If you have a problem with “Installed Watts” then reform the way the entire planet counts the sales of every single good and service in existence, then get back to us. “Installed Watts” is just a sales figure. There are more important hills to die on.

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The point is to only use data that has some meaning. Just because a bad data set it out there doesn’t mean you should use it.

You could use that data and apply some science to it and have a way more meaning full conversation.

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“Installed Watts” does have meaning. It’s a sales number. People don’t walk into a store and buy a PV array in a cardboard box, take it home and plug it in. It’s not a consumer-friendly appliance with a fixed and predetermined output. It needs to be installed — usually by a certified professional. The product isn’t ‘sold’ until it is on the roof, hooked up, grid-tied, verified to be working and certified… i.e. “installed”. That’s when payment is due and the transaction is completed.

Actual, real-world performance is unknown — and unknowable — prior to installation. Only data collection over the course of at least a year would allow even a first-approximation to be made. Past performance is also no guarantee of future performance because of the multitude of variables involved. So you couldn’t actually say — for sure — what the utilisation of any solar array would be (or any other good or service, for that matter) unless you monitor it for its entire life and then produce a graph at the end. No accurate figure can be determined in advance. It’s just not possible to “science it”. What you want to do requires magic and the ability to see into the future.

“Installed Watts” is fine for sales and gives owners an idea of the likely peak output. There is no better way to measure the adoption rate of solar than by looking at how much people are actually installing. That is a fundamentally meaningful and useful thing.

PS: The folks that actually need to have “meaningful conversations” about the output of solar arrays are the network/grid operators. They don’t rely on the “Installed Watts” figure. They use actual live sensor data and meters to monitor array output (at 15-minute intervals in this neck of the woods). The conversations they have (that require accurate numbers) aren’t remotely similar to the conversations that you and I are likely to have. Accuracy helps them, it doesn’t help us.

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Key issues I have with SWB disucssion:

  • Most of the tech comes from China. Being so dependent on one country is not good, especially if that country is not a democracy. Germany learned that the hard way with Russia and natural gas.

  • While solar panels got cheaper, installation still is not cheap. Solar installers lie about the savings and use fantasyland calculations. In many cases a solar investment will not break even. I often hear the phrase “You basically have to have solar if you own an EV”. When I ask “Why?” people realize that they just repeat after the solar installer and have ever actually thought about it.

  • I don’t like the egoistic autarchic approach to energy. Batteries in my home are neither economical nor environmentally a good idea. That should be the job of my electricity provider. Economics of scale and diversity factor play a big role here. I don’t like the “the world around me can go into chaos, but I still have a working fridge and PS5” vibe some people have with their battery installations.

  • People often don’t understand how you plan grids. You plan for the peak demand. Sure we can maybe shift some peaks to get the peak down. But you still plan for peak.
    Since a solar panel can offer 0W in the worst case, it contributes 0W to that peak.
    Yes, 0W! Sure it can indirectly contribute. We can install hydro or batteries. The hover dam offers 2GW and can sustain that for some time. So we can calculate the hover dam with 2GW to your peak calculation. If I use the peak here eia.gov, we would need 370 hover dams to cover the peak demand. I am not saying that this is unrealistic, I am not saying this is bad, I am not saying this is not feasible, I am not saying that there are no other technologies.
    I am only saying, storage is not free. So I disagree with:

Fossils unfortunately are almost free. Panels are very cheap. Everything else is not.

So I don’t really see fossils going away anytime soon, unless we find a dirt cheap storage solution. Just like with EVs, the transition will be a lot slower than what we tech nerds imagine. In 2015, I used to be pretty sure that no company would sell a gas cars in 2030.

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I am working to add 1000sqft of conditioned space to my household in the the next month in the form of 5 shipping containers in my back yard(4 20ft 1 40ft).

Last week I got the tops of the containers painted with apoc 243 from lowes. It is independently tested for 75% heat reflection after 3 years. It dropped the internal temperature in the container with an air conditioner and no insulation yet from a peak of 94f to a peak of 78f.

I am currently adding 3 inches of continuous polyiso foam boards to the inside of the containers.

2 weeks ago I cut the holes for the dual hose portable air conditioners.
I live in a bad neighborhood, and people steal mini split compressors, I needed something where all of the expensive bits were inside the container. The air conditioners are inverter type (so they can ramp down to meet a target temperature) and 1kw each. They also work with if this then that, so I will be able to automate them with a humidity sensor later.

I am in Mobile Alabama, during the summer the temperature swing is in the low 90s at night, with a summer high of 117 in the shade. The humidity is between 60% at night and 85% during the day when it isn’t raining. We get 68 inches of rain a year average. I am planning to bring 5 air conditioners online primarily for dehumidification, but also to make the internal temperature tolerable year round.

We get periodic hurricanes. I have a generator. Hopefully next time we lose power, a container will be easier to keep a comfortable temperature than the house. We usually have no power for about 5 to 10 days a year, usually due to storms. The house is build in 1954 and stupidly insulated, ie the studs are 24 inches apart, not 24 inches on center, and the wall fiberglass batt insulation used was for 24 inches on center, leaving a 1.5 inch gap next to each fiberglass batt for the heat to bypass. Instead of tearing the house down and starting over, I have an oversized air conditioner which runs 24/7 from March to October, supplemented by portable air conditioners in my office and bedroom. Over the summer we usually use 4000kwh ± 800kw for 1000sqft. In the winter we use around 1600kwh, usually at night. I can’t do much about the insulation, but we get lots of sun, so I hope to get the sun to reduce my bills.

I am not putting solar on the roof of the house yet because the mounting hardware costs more than the panels, and because the roof rafters are 2x4 trusses, and the sheathing is 3/8 3 ply, and can’t hold my weight (The guy I hire to clean branches off is 115 pounds, and he has to be careful). I can walk on the shipping containers. I may hire someone to put solar on my house roof later. If I was to do the work on my roof I would need to tear the roof off, take the sheathing off, sister the rafters, put new thicker sheathing on, then put a new roof on, then add solar. Easier to just hire someone who is smaller than me, and won’t fall through to do the install, though I doubt the roof is strong enough. It is probably safe to install on a non-flammable portable building (shipping container). If it got inspected I suspect that my house roof structure would be found insufficient for solar.

I am on the fence if I am going to screw it to the roof of the containers, or just use magnets. I can get 5kw on the 40ft container, and 2.5kw on each of the 4 small ones. for 15kw total.

I am looking at
a1solarstore.com

There are always some panels within 200 miles that I can buy for about $100 for around 400 watt, about $0.25 per watt.
The cheapest panels are 385w 66in by 39in. ie 18 square feet. On the long container (the one that gets the most sun now) I can fit 2 rows of 7 panels for around 5kw.

For inverters I am looking at

off grid inverters
Alabama power pays $0.02/kwh.
either eg4 or growatt.

When the city power goes out, I don’t want to run the generator at night (they get stolen), so I would like to have enough battery to run 1kwh overnight, call it 10 hours. With 20 hours of run time we may be able to not have to run the generator at all, and just use solar.

So I will deploy the big container first, then the rest.

I am looking at this kit to start, then once I have something working, I can build off of it.

I could save money on batteries, and do the china import thing, but if we are going to spend a week a year in it due to unreliable city power, I am certain that my wife will be happier with me if there are not exposed wires. I can go more economical and diy after we are not going to be spending a week in 96f and 80% humidity. The solar inverter can turn on the generator. Also my breaker box will have an interposer so that the generator and street power can’t be on at the same time.

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TBH if you can hook up a charger to a 12V battery then you can install a solar panel or many of them.

If you’re electrically challenged that’s one thing… but unless your solar panels are from the early 1990’s then they have integrated bypass and one-way diodes.

It does get a bit more complicated when going battery-less and tying directly to grid power… you usually go series to raise the voltage and reduce conversion losses. But it’s not rocket science.

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This is also true for all power generation. You don’t know how long you will run a diesel generator. Or a nuclear plant, for that matter - unexpected shutdowns do happen. Solar is a bit more unreliable in that it is weather- and season based, but it is possible to get ballpark numbers of any installation based on direction and solar radiation to that particular spot.

The uncertainty is just more pronounced with Solar, since a lot of solar is bought by home owners and thus these figures become much more visible.

I agree. Why is SWB coming from China though? It’s not as if the panels were invented there. It is because China is the world’s factory, combined with a ton of incentives to make the tech cheap and affordable.

In other worlds, since we in the west slept on the tech China took up the ball. Stupid by our standards but here we are.

Now, we can either start doing as the Chinese or watch the Chinese outcompete us and make the western world the “Development nations”. And that is entirely our choice at this point. Manufacturing of solar can and is already moved to West, batteries are a bit trickier as seen with NorthVolt in Sweden among other things.

You are not wrong, per se, but you should also be aware Solar installations are, on average, 4x as expensive in the US as, say, Europe. And despite that, the US is building solar like CRAZY.

On the contrary, batteries in the home makes a ton of sense and are definitely more environmentally friendly than the alternatives. If you burn wood, for instance, that is still polluting the air and releasing a lot of nasty crap in the air around your home, even if it is CO2 neutral (let’s assume it is, as the discussion is mostly academical in either case). I will make a writeup on SWB structure in the near future, but the short gist of it, is that it is utilizing battery buffers on every level to provide better grid stability than even Nuclear.

Now, big batteries in the home, I agree, does not make sense.

You are not wrong, but two things mitigate this to make it a lot less of a problem; HVDC transmission and time shifting via grid batteries. You also need to take into consideration that all power is added, so it is not so simple as just “planning for peak loads” - on the peak lows, too much energy could make transformers explode.

Battery buffers work to make a more stable grid regardless of energy delivery.

The finns are already on that actually, literally: https://polarnightenergy.fi/

Thermal Sand Storage, yeah baby yeah! :grin: But still not out of research phase and maybe it never will be. At the same time, new, cheaper and more efficient batteries are coming to town, Sodium batteries for instance are poised to lower battery costs by another 25% the coming 2-4 years. So if storage is not there, it soon will be.

That is actually still on. By 2030, EVs will have a lower purchase price in every segment than a corresponding ICE vehicle, and it already is in some segments. Price is not everything, it will take a bit longer to get quality and comfort in an EV to where ICE are across the board (even with perfect charging), but ICE sales are already collapsing globally.

There are however two big buts here:

  1. New cars have gotten FREAKIN EXPENSIVE, the same class of car that cost $20k 15 years ago is now $45k. Affordable segment is down the drain. Tesla is one of the best deals with $35k, and that is just because corresponding ICE is $40k+ - but we need the $15k-$20k crappy segment to come back for mass adoption. In the meanwhile, people stick to what they have until parts rust off and fall by the side.

  2. The replacement rate. People aren’t going to rush out and buy an EV the second they see one they like, a car is a big purchase for most people. As such, most won’t replace their car with an EV until they are in the market for a new car. Currently the replacement rate is anywhere between 2%-5% of the fleet, depending on state and how the regional economy is doing. The replacement will pick up to 10% for a few years and then there will be laggards, but will there still be petrolheads in 2040? You betcha.

Globally EVs have cornered ~15% of the market and this is slowly rising, in China this is 50%+ now.

I’ll try to change the OP of this thread during the weekend so we can try and steer a little bit more towards SWB discusssion proper, what it means and why I believe it will take over the market eventully. :slight_smile:

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But that is not the comparison I made.
I compare 1000 homes having a 2kWh battery vs my grid provider having one 2000kWh battery.
The later is more eco friendly and cheaper.
The only disadvantage it has, is that Thomas Müller with his one million Euro single family home (which is another huge topic!) can not feel good about himself. For some strange reason, a PV panel and some home grown tomatoes are enough for Thomas Müller to feel autarkic.

I hope so. But at the same time, if I got a doller for every time someone invented a new breakthrough battery, I could quit work.

That is a another fantasy I heard for years. It is like Elon Musk and self driving cars, it is always just 5 years away.