It's cool idea (very similar to the Goal Zero system). But I have to say the sketchy Alibaba-level photoshopped product shots of the main battery unit don't add a lot of confidence.
Yeah totally agree. The other guides on the site I've built, tested and lived with myself for the past 2-something years (since the original build below). But it's always been affiliates – this is my first time shipping and backing the hardware myself. I haven't got updated images of the samples yet – so apologies for the low image quality. If there are people out there who want systems like this, we'll have updated, glammy photos soon enough :).
On a different note, I'm hoping to be able to partner with these guys to solve the "window-gap" problem:
https://www.swrtec.com
I think you should just be more transparent in the stage of delivery you are in on your site. This is a niche product for enthusiasts and I think an enthusiast customer would be fine supporting you if you were more clear about how your production is going on the kinds of problems you might hit delivering instead of trying to appear like it's all ready to go.
The rest of the site is more along those lines I'd argue – and it's gotten around 15 hits a day from the "niche" community for the past few years.
Though the stage of the project needs to be better fleshed out, a little marketing (even if it's probably too early on this pre-sale) goes such a long way I'd argue. Until this HN post got upvotes for the somewhat clickbait-y title I was not sure anyone in the world would care or even find this article or care about the concept :)
Good call on "Alibaba-level", I was able to find this unit on there. Not gonna link because I don't want to stir up trouble.
But I'd like to set up a good system for my vehicle, and products like this make me nervous. China mass-produces a lot of good stuff but they've also got a deserved reputation for cutting corners when nobody's looking. An 18650 that's missing its overcharge circuit will happily self-ignite and take my beloved vehicle with it.
Remember all those reports of hoverboards spontaneously combusting a few years back? That was eventually traced back to bargain bin Li-Ion batteries from China. Before that, there was the spate of knock-off replacement batteries for cell phones that came with a free extra crispy option.
Larger companies doing business in the US fear the FTC and state governments enough to often have some form of electrical QA on anything they sell with a Chinese origin. In this case though I'd be assuming all the risk and I don't have the expertise to evaluate it for quality and safety myself.
Just out of curiosity is grid based green energy available in your area?
Here in Germany we can choose providers, and most have fully renewable options.
For a little backup energy autonomy a home solar system is definitely fun but you will probably never offset the sunk carbon from the systems manufacture.
I find for me solar definitely drives an awareness that energy isn’t limitless but it’s usually substantially greener to just do that as a mental exercise and buy the power from the grid.
That said, having your own setup definitely stokes those nice “I’m autonomous” feelings. :)
"Green" energy is based on Green certificate that are sold on an exchange, and can be used at anytime during a year, in any connected countries, they are far from real fully renewable or even no marginal carbon.
> Whoever buys the certificate can then claim that a certain amount of renewable electricity has been produced. Here’s where the problem is: the trade of certificates is not limited in space nor in time. It means that you can buy a certificate from a region disconnected from your electricity grid (space), or from the past (!) without making sure the electricity was stored (time).
I've commented before on HN[1] about how this critique of energy certificates doesn't make any sense, the fact that you can time-shift consumption is a feature, not a bug.
It helps if you think about it as a subsidy, which it is. You charge your battery on electrons produced at a coal plant and pay for e.g. 1 kWh of solar energy to be produced. That energy is then used to say charge a phone you just bought before it's delivered to you.
It's not as superficially emotionally satisfying as imagining that all your electrons are "pure", but they're fungible. Just as you could say emit 1 ton of CO^2 and sequester 2 tons of CO^2 somewhere else at some other time.
Did you just undo the pollution you emitted? I think so, but I think using your criteria you'd need to put that "cleanup" effort in another set of scare quotes.
For me, the problem with green energy certificates is as soon as my government set itself a target for green energy, they made a bunch of really sketchy classifications in order to hit their own target.
To the extent that you can remain solvent while trying to single handedly warm up the planet, it's in the interest of the rest of us to give you an incentive to shift that energy consumption to a sustainable provider.
This is a perfect example of exactly the sort of case energy credits excel at, since you can shift the consumption to a different time and location.
> you can remain solvent while trying to single handedly warm up the planet,
I'm fairly sure we have some kind of misunderstanding, and I don't see exactly what you are getting at. Anyway the point of this whole scheme wouldn't be to warm the planet. It would be to put solar panels in a location with a lot of sun and cheap land, to produce certificates as cheaply as possible.
Now having nothing useful to do with the resulting energy, since it's so far away from the grid, just flush it down the drain so to speak, by driving a resistor.
The esoteric reader may notice a certain similarity to the practice of a sending a scapegoat to the desert for the purpose of purifying sin.
I realize what you meant, in practice there's a large amount of legislation around this sort of thing and the people writing it aren't morons and have heard of things like the cobra effect[1].
But maybe I'm wrong and there's lots of investors building power plants purely to waste energy and make a point. We just haven't heard much about them because the joke got tired within a week of operations and they decided they might as well connect it to the grid instead to recoup their investment.
- the first picture might not really be landlord-friendly; there are codes on what you can install outside your window and how (besides looks, you wouldn't want this to fall on someone)
- shocking price - the wording alone would put me off of even being interested in the product; but putting that aside, $500 doesn't seem shocking to me at all
- same tech battery as tesla; is this the "lithium-ion" part? come on
- True. Most people I know ended up ziptie-ing the panel(s) on their rooftop or in the back yard (more sunshine hours).
- Yes. I meant for a 0.2kW, 5kWh, 500W system this is shockingly low. I'm tired of people getting ripped off on Amazon for drop-shipped stuff. I think $499 incl. shipping is shocking, but agree that the wording needs to be better. This is an early landing page :)
- 18650 cells were used in early Tesla cars (to the best of my knowledge, they're still used in S and X?). Most people who are new to solar/storage are looking at AGMs and thinking "this is way more expensive" (but of course you get more cycles, better full discharge, etc with Lithium). Agreed that the wording needs to be better.
- 5x more power than the other kits on the website, which can output around 100W AC. This system drives 500W AC. Again, thanks for the pointer. This will be improved.
How about "landlord-friendly design," and "consumer-friendly prices," "renter-friendly" or somesuch.
Think about what you are trying to communicate. You can use "show-don't-tell" to imply superlatives. IE, let the reader colour in their own adjectives.
The messages are simple: You can intall it yourself in a rental. It costs $500.
You already show the price, and the specs. If you want/need more context, provide more context. Maybe price comparisons. Maybe you can contextualise the specs: battery can power these many devices, for this amount of time. The battery will charge in this amount of time, on an average October day.
Try to keep the number of messages small and think of your words in a utilitarian way. They have specific jobs. Are they trying to inform, convince, associate with another product? Do the simplest thing that gets the job done.
Keep chopping! Copywriting isn't that hard, but you should treat it as crafting or artsing. Chunk & edit at different size-levels. Sentences. Words. Paragraphs. Do all of them do a job? Are they doing it well? Being concise is more important in copywriting than in code.
"Our new off-grid renewable energy micro-grid system is here! We tried to build the best system we possibly could at the lowest possible price."
Too many adjectives! What's the predicate?
Our
new | off-grid | renewable | energy | micro-grid | system
is here
1) Have a native English-speaker do some proof-reading and tone down the level of excitement to a credible level. The overall idea makes sense.
2) I've been in apartment buildings in SE Asia without window awnings where direct sunlight made the unit literally an oven.
In that region, AC is $1000+/month when adjusted for COLA, so they try not to use AC. There is a huge market for a $100 window-mounted solar draw fan that doesn't necessarily need a battery or even an electricity output - just rotate the draw fan during sunlight.
4) FYI: In the Bay Area, you don't have much of a choice in grid provider. PG&E covers 100% of the region, and there's one local utility on the Peninsula and one in Alameda, last I heard. They all prioritize hospitals and emergency services, so in a blackout, may not provide expected redundancy.
This reeks of spam, and that picture of the module on the apartment floor is not even real, its clearly photoshopped and a digital render of the product.
All you need to know per registrar details of this URL:
Creation Date: 2017-09-29T02:59:02Z
Updated Date: 2019-09-29T07:55:04Z
Registry Expiry Date: 2020-09-29T02:59:02Z
Kits like these are, IMO, pretty important steps along the way. First, they're accessible. People get their feet wet, learn. Since the technology is improving, it can be a rewarding "hobby" project. Every few years there will be upgrades available and prices will improve.
A $500 kit has to be simple. That's a great environment for innovative contributions.
Innovation & cultural change happen slower if the only Tesla, Samsung, power companies and other giants are playing. Remember that the web, and most of its innovations did not happen @ google or facebook. They were originated by many small players, and later collected into those big companies.
Good luck to you. If you can establish a beachhead with this kit, you should have backwind to help you going forward. Batteries are the limiting factor, and they're improving.
Self install plug & play solar is a big opportunity imo.
Because install costs are such a big share of system costs.
The tipping point will probably be a company that ships a modular system that can be installed with only a mobile phone + drill & can scale from an apartment to a large building.
Fraunhofer ISE has worked on this vision quite a bit.
Come on, now this is over the edge :D Why didnt you rather say I am using it in electronic cigarette. Or maybe that it is used, like everywhere, from laptop batteries to power tools even before Tesla existed. And yeah it is used by Tesla too, like every other company that uses li-ion batteries and needs this sizing factor.
I saw that video recently and it does not include some things that made me stay away: labor cost, expertise and parts availability.
- I cannot buy all the parts where I live (Eastern Europe) and not for the price in the video
- I am decent with a soldering iron and quite ok with a screwdriver and power tools, but welding live batteries is out of reach for most people
- it takes quite some time to do that work, not included in the $650
- I would like to modify that setup by adding more batteries or different batteries (like big motorcycle Li-Pol batteries), but I don't have the expertise to change the setup and I have no time to get that expertise, it is not something you learn in a few hours
So it is a good proof of concept, but not really something to mass replicate by people at home.
> welding live batteries is out of reach for most people
Battery grade spot welders are $100-250 on Amazon and it’s easy to do, but I have to admit, even after welding hundreds of batteries I’m still nervous doing it because I’ve seen first hand what lithium ion batteries are like when they catch fire (unrelated incident where that happened).
Putting 3.5kWh of chemical energy in one box is pretty scary unless you're a professional. I wouldn't leave that thing unattended and always have something nearby that can extinguish a battery fire.
This attitude is why people in New Jersey and Oregon aren't even allowed to pump their own gas. But hey, if it works for you, I guess it'll just have to do for the rest of us.
Hacking with low voltage electronics is one thing. But a 3.5kWh lithium ion battery pack is not something you ever want to "hack". It has enough energy to burn down a house in minutes. Designing your own solar at the component level is fine. But no amateur should ever attempt to build a battery pack of that size any more than they should attempt to build a bomb.
It has enough energy to burn down a house in minutes.
Meh, so does every electrical outlet, matchbook, and cigarette lighter in your house. Unless and until I start to hear a lot of horror stories about people who burn down their houses with homebrew lithium battery packs, I'll refrain from clutching my pearls.
What does seem to happen frequently are fires caused by sketchy prefabricated battery packs that are commercially available but probably shouldn't be. I'll put my soldering, electronic assembly, and spot-welding skills up against some random Chinese wage slaves any day.
You'll have problems with shadows, window tints, bad angles...
Solar panels work best in direct sunlight when they are angled so they face directly into the sun. If you stick a solar panel in the window, any tint in the window will reduce output. Bars, ect, will put shadows and reduce output. Assuming your window isn't very wide, the frame of your window will cast a shadow...
So, unless you can get the panel on a porch, roof, fire escape, ect, don't bother.
Anything between you and sunlight is a large decrease. Heck, hanging at the wrong angle is a big loss. Does the window face the sun directly? Far bigger issue really. And 'directly' doesn't really mean anything since the sun's direction changes constantly.
You say “I built”, but the inverter/charger/battery is an off the shelf unit - I have one from the same OEM here, 400Wh model, same outputs (but 230v ac), and I got a folding 150W panel for go with it. Works great as a stopgap for lighting, network stack, but 500Wh doesn’t go far with, say, a laptop, particularly after all the conversions.
Anyway. I guess your primary value add is in bundling it all together and telling people where to stick stuff via zoom, but “I built” is a bit misleading. I designed and installed a 5kva 4800 solar watt 42kWh system here, but I wouldn’t say I built it - I just stuck the bits I ordered together.
I think that the original poster use of "I built" to mean sticking bits they bought together in a way that works is pretty much layman usage of the phrase.
I suppose you might want a more stringent usage on HN, but I personally find it reasonable.
I built my PC. I bought ~6 things off of Newegg and stuck them together. Combining pre-existing modules into a system is a valid use of the word "build."
Interesting, but a bit hard to make the economic case for it - it looks more suitable for camping/cabin use cases? It's not going to significantly reduce your energy consumption from the grid, since it doesn't tie into the house circuits.
Cheaper (and potentially lower quality in line with cheaper price). Jackery is over double the price for a comparable setup ($600 for 2x panels alone via Jackery’s site).
Costs $500 + planetary manufacturing costs of the battery, and panel, plus their pollution cost post-use.
Based on constant use, it generates $50 of electricity per year + saves plantary production costs of electricty by traditional means.
So providing the battery and panel don't fail or decline in function, it financially pays for itself after 10 years of constant use, realistically probably more like 8 or 9 years when you factor in rising domestic electricity costs.
Looks like a terrible investment to me. Especially when you factor in the planetary costs of the physical production.
Adding one or 2 more panels would increase the output a lot with a small increase in price, making the financials a lot better. Yes, it is a bad deal as it is now.
The average payback on whole home solar is 7.5 years, so 10 isn't too far off normal.
My problem is that semi-permanent installation at this size is of questionable utility; I don't want to have to juggle my electric usage between this and the regular grid in order to maximize my solar, that sounds incredibly inconvenient. Of course there are solutions to this, but they're not renter friendly.
Portable? For camping?! Maybe for glamping, where you have generous luggage space and don't have to carry it far (or at all). But then, you could use a camper mounted device already.
If you are going for camping, just buy a GoalZero battery system from Costco. They are literally the same thing, significantly higher capacity models available and actually a proven/working product instead of this crowdfunded shit that's just going be some rebranded chinese device.
Years ago when I lived in an apartment I was tempted to build a similar setup. I was going to plug my refrigerator into the inverter, and use a rely to switch back to grid power once the battery was depleted.
Anyway, some kind of rely to switch back to grid power when the battery is depleted would make this really cool.
The core idea is great, but the details are not. I am looking at something like that for a while and these are the comments:
- the capacity is too low. For something to put on the roof of the car when going somewhere it as at the limit, but the usability is low: to power a few mobile phones a battery bank is much cheaper, to generate electricity for a few days of camping it is too low. For home it is way too low, I would add a few batteries and more panels, maybe 500W for panels and >2k for batteries. If I have a power failure I need something to keep my desktop and fridge running over night and run on solar during the day, that is the minimum where I consider buying, otherwise a UPS will give me more value.
- the price is too high for a gadget and with such a low capacity it is a gadget, not a serious electricity source. Probably a higher price with a lot more capacity is a better deal.
Yeah, I don’t understand why they are only doing 500W for the batteries unless ultra portable size was the goal. I’ve made lots of batteries using Samsung 18650 cells (via a spot welder and nickel strips) and 500W is fairly simple to do. One of my drones draws over 3,000W as an example.
Further, usually you care more about Wh and not W alone anyway. For example, the Samsung 25R 18650 (which I use frequently) is about 80W for a single cell fully charged, but is only up to about 10Wh. So for the 500Wh claim, that’s around $100 in batteries if new and Samsung, cheaper if alternative brands.
So assuming you’re a DIYer (which obviously this listing isn’t targeted directly at):
Batteries - around $100
500W inverter/charger - around $80
2x100W solar panels similar to ones pictured - Around $150
105 comments
[ 1.8 ms ] story [ 206 ms ] threadhttps://news.ycombinator.com/item?id=14821478
https://news.ycombinator.com/item?id=15425324
On a different note, I'm hoping to be able to partner with these guys to solve the "window-gap" problem: https://www.swrtec.com
https://www.youtube.com/watch?v=KYezJJv_pEA&feature=emb_logo
The rest of the site is more along those lines I'd argue – and it's gotten around 15 hits a day from the "niche" community for the past few years.
Though the stage of the project needs to be better fleshed out, a little marketing (even if it's probably too early on this pre-sale) goes such a long way I'd argue. Until this HN post got upvotes for the somewhat clickbait-y title I was not sure anyone in the world would care or even find this article or care about the concept :)
But I'd like to set up a good system for my vehicle, and products like this make me nervous. China mass-produces a lot of good stuff but they've also got a deserved reputation for cutting corners when nobody's looking. An 18650 that's missing its overcharge circuit will happily self-ignite and take my beloved vehicle with it.
Remember all those reports of hoverboards spontaneously combusting a few years back? That was eventually traced back to bargain bin Li-Ion batteries from China. Before that, there was the spate of knock-off replacement batteries for cell phones that came with a free extra crispy option.
Larger companies doing business in the US fear the FTC and state governments enough to often have some form of electrical QA on anything they sell with a Chinese origin. In this case though I'd be assuming all the risk and I don't have the expertise to evaluate it for quality and safety myself.
Here in Germany we can choose providers, and most have fully renewable options.
For a little backup energy autonomy a home solar system is definitely fun but you will probably never offset the sunk carbon from the systems manufacture.
I find for me solar definitely drives an awareness that energy isn’t limitless but it’s usually substantially greener to just do that as a mental exercise and buy the power from the grid.
That said, having your own setup definitely stokes those nice “I’m autonomous” feelings. :)
https://www.sciencedaily.com/releases/2019/05/190523111408.h...
https://www.aib-net.org/
https://medium.com/electricitymap/why-green-electricity-cont...
> Whoever buys the certificate can then claim that a certain amount of renewable electricity has been produced. Here’s where the problem is: the trade of certificates is not limited in space nor in time. It means that you can buy a certificate from a region disconnected from your electricity grid (space), or from the past (!) without making sure the electricity was stored (time).
I've commented before on HN[1] about how this critique of energy certificates doesn't make any sense, the fact that you can time-shift consumption is a feature, not a bug.
It helps if you think about it as a subsidy, which it is. You charge your battery on electrons produced at a coal plant and pay for e.g. 1 kWh of solar energy to be produced. That energy is then used to say charge a phone you just bought before it's delivered to you.
It's not as superficially emotionally satisfying as imagining that all your electrons are "pure", but they're fungible. Just as you could say emit 1 ton of CO^2 and sequester 2 tons of CO^2 somewhere else at some other time.
Did you just undo the pollution you emitted? I think so, but I think using your criteria you'd need to put that "cleanup" effort in another set of scare quotes.
1. https://news.ycombinator.com/item?id=21681772
To the extent that you can remain solvent while trying to single handedly warm up the planet, it's in the interest of the rest of us to give you an incentive to shift that energy consumption to a sustainable provider.
This is a perfect example of exactly the sort of case energy credits excel at, since you can shift the consumption to a different time and location.
I'm fairly sure we have some kind of misunderstanding, and I don't see exactly what you are getting at. Anyway the point of this whole scheme wouldn't be to warm the planet. It would be to put solar panels in a location with a lot of sun and cheap land, to produce certificates as cheaply as possible.
Now having nothing useful to do with the resulting energy, since it's so far away from the grid, just flush it down the drain so to speak, by driving a resistor.
The esoteric reader may notice a certain similarity to the practice of a sending a scapegoat to the desert for the purpose of purifying sin.
But maybe I'm wrong and there's lots of investors building power plants purely to waste energy and make a point. We just haven't heard much about them because the joke got tired within a week of operations and they decided they might as well connect it to the grid instead to recoup their investment.
1. https://en.wikipedia.org/wiki/Cobra_effect
- the first picture might not really be landlord-friendly; there are codes on what you can install outside your window and how (besides looks, you wouldn't want this to fall on someone)
- shocking price - the wording alone would put me off of even being interested in the product; but putting that aside, $500 doesn't seem shocking to me at all
- same tech battery as tesla; is this the "lithium-ion" part? come on
- 5x more power - what is this supposed to mean?
- True. Most people I know ended up ziptie-ing the panel(s) on their rooftop or in the back yard (more sunshine hours).
- Yes. I meant for a 0.2kW, 5kWh, 500W system this is shockingly low. I'm tired of people getting ripped off on Amazon for drop-shipped stuff. I think $499 incl. shipping is shocking, but agree that the wording needs to be better. This is an early landing page :)
- 18650 cells were used in early Tesla cars (to the best of my knowledge, they're still used in S and X?). Most people who are new to solar/storage are looking at AGMs and thinking "this is way more expensive" (but of course you get more cycles, better full discharge, etc with Lithium). Agreed that the wording needs to be better.
- 5x more power than the other kits on the website, which can output around 100W AC. This system drives 500W AC. Again, thanks for the pointer. This will be improved.
Think about what you are trying to communicate. You can use "show-don't-tell" to imply superlatives. IE, let the reader colour in their own adjectives.
The messages are simple: You can intall it yourself in a rental. It costs $500.
You already show the price, and the specs. If you want/need more context, provide more context. Maybe price comparisons. Maybe you can contextualise the specs: battery can power these many devices, for this amount of time. The battery will charge in this amount of time, on an average October day.
Try to keep the number of messages small and think of your words in a utilitarian way. They have specific jobs. Are they trying to inform, convince, associate with another product? Do the simplest thing that gets the job done.
Keep chopping! Copywriting isn't that hard, but you should treat it as crafting or artsing. Chunk & edit at different size-levels. Sentences. Words. Paragraphs. Do all of them do a job? Are they doing it well? Being concise is more important in copywriting than in code.
"Our new off-grid renewable energy micro-grid system is here! We tried to build the best system we possibly could at the lowest possible price."
Too many adjectives! What's the predicate?
:)1) Have a native English-speaker do some proof-reading and tone down the level of excitement to a credible level. The overall idea makes sense.
2) I've been in apartment buildings in SE Asia without window awnings where direct sunlight made the unit literally an oven.
In that region, AC is $1000+/month when adjusted for COLA, so they try not to use AC. There is a huge market for a $100 window-mounted solar draw fan that doesn't necessarily need a battery or even an electricity output - just rotate the draw fan during sunlight.
4) FYI: In the Bay Area, you don't have much of a choice in grid provider. PG&E covers 100% of the region, and there's one local utility on the Peninsula and one in Alameda, last I heard. They all prioritize hospitals and emergency services, so in a blackout, may not provide expected redundancy.
"Off-grid" for an hour or two?
Kits like these are, IMO, pretty important steps along the way. First, they're accessible. People get their feet wet, learn. Since the technology is improving, it can be a rewarding "hobby" project. Every few years there will be upgrades available and prices will improve.
A $500 kit has to be simple. That's a great environment for innovative contributions.
Innovation & cultural change happen slower if the only Tesla, Samsung, power companies and other giants are playing. Remember that the web, and most of its innovations did not happen @ google or facebook. They were originated by many small players, and later collected into those big companies.
Good luck to you. If you can establish a beachhead with this kit, you should have backwind to help you going forward. Batteries are the limiting factor, and they're improving.
The tipping point will probably be a company that ships a modular system that can be installed with only a mobile phone + drill & can scale from an apartment to a large building.
Fraunhofer ISE has worked on this vision quite a bit.
> 18650 Same lithium battery tech used by Tesla
/sarcasm on
Come on, now this is over the edge :D Why didnt you rather say I am using it in electronic cigarette. Or maybe that it is used, like everywhere, from laptop batteries to power tools even before Tesla existed. And yeah it is used by Tesla too, like every other company that uses li-ion batteries and needs this sizing factor.
/sarcasm off
For now, I don't have any use for it as the power never goes out here. But good luck!
Maybe these will be as normal in the future as getting a jerrycan of gas is in some places.
https://www.youtube.com/watch?v=PVnQ87Fvsk4&
Great bang:buck ratio, at least if you can get a good price on that many 18650s.
- I cannot buy all the parts where I live (Eastern Europe) and not for the price in the video
- I am decent with a soldering iron and quite ok with a screwdriver and power tools, but welding live batteries is out of reach for most people
- it takes quite some time to do that work, not included in the $650
- I would like to modify that setup by adding more batteries or different batteries (like big motorcycle Li-Pol batteries), but I don't have the expertise to change the setup and I have no time to get that expertise, it is not something you learn in a few hours
So it is a good proof of concept, but not really something to mass replicate by people at home.
Battery grade spot welders are $100-250 on Amazon and it’s easy to do, but I have to admit, even after welding hundreds of batteries I’m still nervous doing it because I’ve seen first hand what lithium ion batteries are like when they catch fire (unrelated incident where that happened).
Perhaps there are other sites where your position will fit in better. This one is called Hacker News.
Meh, so does every electrical outlet, matchbook, and cigarette lighter in your house. Unless and until I start to hear a lot of horror stories about people who burn down their houses with homebrew lithium battery packs, I'll refrain from clutching my pearls.
What does seem to happen frequently are fires caused by sketchy prefabricated battery packs that are commercially available but probably shouldn't be. I'll put my soldering, electronic assembly, and spot-welding skills up against some random Chinese wage slaves any day.
Puttin solar panels on the outside of my apartment would be diffcult and dangerous.
But putting them inside, so they get sunlight through a window would be easy.
Heck, I can even see me using solar panels instead of blinds.
Would that work? Or does the sunlight lose too much energy when going through glass? If so, how much energy gets lost?
Short answer: No
You'll have problems with shadows, window tints, bad angles...
Solar panels work best in direct sunlight when they are angled so they face directly into the sun. If you stick a solar panel in the window, any tint in the window will reduce output. Bars, ect, will put shadows and reduce output. Assuming your window isn't very wide, the frame of your window will cast a shadow...
So, unless you can get the panel on a porch, roof, fire escape, ect, don't bother.
Anything between you and sunlight is a large decrease. Heck, hanging at the wrong angle is a big loss. Does the window face the sun directly? Far bigger issue really. And 'directly' doesn't really mean anything since the sun's direction changes constantly.
Anyway. I guess your primary value add is in bundling it all together and telling people where to stick stuff via zoom, but “I built” is a bit misleading. I designed and installed a 5kva 4800 solar watt 42kWh system here, but I wouldn’t say I built it - I just stuck the bits I ordered together.
I suppose you might want a more stringent usage on HN, but I personally find it reasonable.
Based on constant use, it generates $50 of electricity per year + saves plantary production costs of electricty by traditional means.
So providing the battery and panel don't fail or decline in function, it financially pays for itself after 10 years of constant use, realistically probably more like 8 or 9 years when you factor in rising domestic electricity costs.
Looks like a terrible investment to me. Especially when you factor in the planetary costs of the physical production.
My problem is that semi-permanent installation at this size is of questionable utility; I don't want to have to juggle my electric usage between this and the regular grid in order to maximize my solar, that sounds incredibly inconvenient. Of course there are solutions to this, but they're not renter friendly.
Is that what the gatekeepers are calling "car camping" now? Not everyone carries their camping gear on their backs.
Anyway, some kind of rely to switch back to grid power when the battery is depleted would make this really cool.
- the capacity is too low. For something to put on the roof of the car when going somewhere it as at the limit, but the usability is low: to power a few mobile phones a battery bank is much cheaper, to generate electricity for a few days of camping it is too low. For home it is way too low, I would add a few batteries and more panels, maybe 500W for panels and >2k for batteries. If I have a power failure I need something to keep my desktop and fridge running over night and run on solar during the day, that is the minimum where I consider buying, otherwise a UPS will give me more value.
- the price is too high for a gadget and with such a low capacity it is a gadget, not a serious electricity source. Probably a higher price with a lot more capacity is a better deal.
Further, usually you care more about Wh and not W alone anyway. For example, the Samsung 25R 18650 (which I use frequently) is about 80W for a single cell fully charged, but is only up to about 10Wh. So for the 500Wh claim, that’s around $100 in batteries if new and Samsung, cheaper if alternative brands.
So assuming you’re a DIYer (which obviously this listing isn’t targeted directly at):
Batteries - around $100
500W inverter/charger - around $80
2x100W solar panels similar to ones pictured - Around $150
20ft of cable - around $20
https://news.ycombinator.com/item?id=23317666 https://news.ycombinator.com/item?id=14821478