Were you able to disconnect that home from the grid? Most places you're required to maintain a grid connection unless the home is in an exceptionally remote location.
While pricing tends to be usage-based, true costs tend to be dominated by the capital expense of building base-load capacity for the few days your home might need to run fully on grid power. So as long as you're connected to the grid, you're still forcing the utility to spend about the same amount of money even if you only use grid power a few days out of the year.
Most solar charge controllers allow a certain amount of PV overprovisioning.
Not really a thing in Toronto.
[1] https://1.bp.blogspot.com/-I5kzJIeV4Ds/VFSHUX3374I/AAAAAAAAA...
This is a good source, population by latitude.
http://www.statsmapsnpix.com/2021/11/world-population-by-lat...
Seems obvious that Norway, Washington State have lots of hydro. Places like Spain and California have lots of steady sun. Scotland, no sun in the winter but lots wind all the time. Those places renewables aren't problematic.
PS: Geothermal can also slash energy needed for heating. Ground sourced heat pumps are the only reasonable small scale solution, but in urban areas going a little deeper starts to make a lot of sense.
Perhaps as a complete energy solution. But it is already the case today that a domestic rooftop solar in Europe (maybe not in the very north) has payback times <10 years. And that's without factoring in batteries which (as the OP describes) are rapidly approaching affordability.
Hamburg is at 53.6 degrees North; Berlin is 52.5. Both are just farther north than Calgary, as a pretty reasonable comparison for the US.
To contrast, New York City is at 40.7 degrees, and Boston is at 42.3 degrees North.
Using an overprovisioned quantity of cheap cells is part of it.
Insulating and air sealing your home well is part of it.
Thermal mass approaches are part of it. Without cheap batteries, it's very possible to store a great many kwh in volumes of soil, water, or sand riddled with pipes and resistive heaters.
This year it has been pointed out that vertical bifacial solar panels radically outperform tilted arrays if snow is a possibility. Expect this to be the new normal at high latitudes as cell area is very cheap now.
Great job! Over the last half a year my feelings about rooftop grid-connected solar (net energy metering, feed in tariff which are subsidised by the electricity bills of others) have changed somewhat, but going off-grid you've put in the investment to be energy independent.
For comparison, I've seen pallets of new 24 410w panels at 58€ per panel (transportation included), hopefully I'll see similar deals in the future when I will ready to jump into solar.
Edit: I'm mostly worried because I don't know how sustainable the industry is when you can buy solar panels at such dirt cheap prices.
Energy costs are THE driving force of prices. The cost of materials is essentially the energy it takes to squire/process/ship them. If energy was free, we would just dig up random patches of dirt and sift it for every material we wanted even in trace amounts. But its not because unfortunately, we are still primarily a fossil fuel economy for many reasons (legacy, price, chemical properties) and their cheap price relative to labour is acting as a subsidie to renewables pricing. So if the availability of fossil fuels deminishes it seemed logical that the price of inputs goes up and so too would renewable manufacturing. We would then see an inverted bell shaped curve on pricing over time. I have long suspected we would see this trend of lowering prices revert around the 2020s. So far I have been pleasantly wrong.
But fossil fuels like almost all minerals is fighting an uphill battle on availability and ore quality as we used the best stuff first. The US isnt fracking at the pace it is because they just wanted a laugh. It is due to the primary "conventional" stuff couldnt keep up. But that is a whole different issue.
If renewables were offsetting fossil fuel usage, this wouldnt be a problem but it is merely being added on top of it. Thus Jevons paradox in full swing. If we can over come that then this whole idea can be thrown in the recyling bin.
When we can make a solar panel with the outputs of a solar panel, then that is the escape velocity moment. And I don't just mean counting the joules and ignoring the energy fungability.
I am much more optimistic about this in the last few years but im not sure we are there yet. It is looking reasonable now.
> At the core of Scott's vision was "an energy theory of value". Since the basic measure common to the production of all goods and services was energy, he reasoned "that the sole scientific foundation for the monetary system was also energy", and that by using an energy metric instead of a monetary metric (energy certificates or 'energy accounting') a more efficient design of society could be made
https://en.wikipedia.org/wiki/Technocracy_movement
If nothing else it's a fascinating lens to view modernity through.
Maybe 20 years ago I had the thought that ever never was enough supply of fossil fuels to lift the remaining 2/3rds of humanity out of poverty[1]. But there is enough solar and wind to give people a low energy middle class life. And the cost reduction since I think can do better than that.
[1] China I think burned half it's coal reserves in last 40 years. Modern China is basically built on coal. And much of the world doesn't have anything like that.
As a point of nomenclature isn't that always the case for any resource?
Given that "reserves" are drill tested known quantities that are tested, proven, modelled, and queued up for mining .. most reserves having been taken past "economic feasibility".
Hasn't the usual pattern in mining for some three thousand years since the oiriginal Rio Tinto Gold Mine been that reserves are mined and as they are exhausted, an exploration phase ramps up to prove inferred resources and raise them to reserve status?
eg: https://www.ga.gov.au/digital-publication/aimr2021/australia...
However panels age which costs ~1% of capacity per year even before they need to be replaced, and global electricity demand tends to increase 2+%/year. So the more solar you install the more you need to install every year just to keep providing the same percentage of total electricity.
On top of this lower prices mean you it's still worthwhile even if a larger percentage of output gets wasted. Similarly, as storage gets cheaper (inflation adjusted) there's going to be more demand to cheaply charge it thus raising the demand for panels.
A 410W solar panel at 29€? I really doubt that honestly. Cheaper than plywood.
Comely divorced from the real world materials and ecology.
470W + even cheaper inverters seems likely.
That's what they said about regular electric grid power too - that it "soon" would be so cheap as to be unmetered. That was half a century ago and it didn't pan out...
Solar power has neither the geopolitical problems nor the squishy 'environmentalist' ick factor of fission. There's no reason not to expect another halving or two of PPP dollar per Watt to follow.
It's an industry that's been driving down prices at an absolutely bonkers rate the entire time it's existed, and any time a company falls behind on that they're immediately in very deep trouble. I think it's basically impossible to make predictions about what an industry like that will be in 8-10 years.
It's $900 + inverters for 10 kWh. A Tesla Powerwall 2 (14 kWh) is $10k (inverter included).
I doubt the inverters cost more than $1k.
Buying cells from CATL, adding a BMS, and putting all in a case is easy but still not trivial. Definitely not plug and play. You can absolutely get dirt cheap LFPs (like other people, I hang out on diysolarforum.com too), but it is not a competitor with the Powerwall unless you want something to tinker with or are simply too budget constrained to buy the brand name product.
P.S. I've never heard of sparky being used as slang for an electrician, sounds very aussie.
When I moved into a new house in Australia I asked the real estate agent if I could extend the fence, and he said I'd need a cheapie to do that.
I said ok but scratched my head as to why it needs to be cheap, only to find out later what he actually said was chippy, slang for a carpenter.
I can understand requiring a license for any power wires behind walls.
I could also see the possibility that it's just an old law that doesn't consider data-only cables which don't have the safety issues that wires carrying power do.
I'm surprised to find out it's aussie slang; I always thought it was slang local to South Africa :-/
We also use sparkie for electrician.
ZA and AUS included. USA less so.
I'd love to add at the very least an ATS to keep my fridge and freezer going when the power goes out during the day, if not a battery but I have little to no documentation on the existing solar install, so i'm reaching out to the county to see if permits have any info. Fun times!
Unlike microinverters that are notoriously unreliable, DC optimizers so far have excellent long-term reliability.
I had exactly the same experience. They absolutely would not tell me the actual system cost, only how much I would save on my current bill per month. It felt exactly like a car salesman only talking about monthly payments, and it was horrible.
They were clearly just doing lead generation for some other company they had no direct connection with, and didn’t even have any idea who to talk to that could even answer my question.
I had way better luck just looking online and paying shipping, which is absurd given how they were presenting themselves.
So not even as good as a used car salesman on an actual car lot, more like door to door used car salesman.
The true value of solar or wind is the cost of the fuel it saves. Nothing more. Even if his numbers come true there's a big problem--bad weather could deplete your batteries. You want to turn to the electric company in that case? You are once again in the situation that the value is only the fuel.
I did my own a couple years ago, and it worked quite well on the first go. I got someone else to build the LiFePo4 battery pack (16 CATL cells for 48v with a JK BMS).
It was fairly easy to build. Mount panels on the roof, and wire everything (PV, battery, grid electricity if you want it, and the output) to the inverter. I added some extra steps to monitor usage and output, and a smart MCB. I also have a small shop that I can feed from solar power if the battery is almost charged and the sunset time hasn't reached yet.
See if you quotation is to export electricity to the grid. Those kinds of setups usually require a certified company to do the installation (to make sure the inverter syncs with the grid), but for off-grid setups, you can definitely DIY.
The setup you describe - lacking microinverters - I think there are options there short of wholesale replacement [disclaimer: I, too, am a self-taught in this field, and so am likely wrong in non-trivial ways]
A lot of the costs of a real install come from the permitting, doing proper upgrades (you might need a new electrical panel), the warranty, the labor, and other costs.
Every time I browse the DIY solar forums it feels like I see 1 person doing things by code for every 10 people cutting corners or playing loose with the rules. YMMV, but take the DIY cost estimates with a huge grain of salt.
So yeah, there are businesses that'll do it.
Going with a door knocking sales rep for home batteries would be madness in most countries but chances are pretty good that in Australia you would get a perfectly decent product.
A 13kWh system is over $AUD10k, and the ROI is on par with the expected lifespan of the battery.
If sodium cells can bring the price down to $AUD100 it would indeed be a massive game changer.
Better to DIY or at least do really good market research first.
This channel on youtube is an excellent resource and explains everything for anyone one who is a DIYer.
For something like this, a worst case scenario is an electrical fire during a drought or a kid gets electrocuted. If you do the work yourself, you're likely on the hook if something goes wrong, even if it's due to a faulty part and you have an umbrella policy that covers liability.
> I keep hoping there will be a bunch of small businesses electrifying everything
There are a few of these per large city; but they serve companies with large budgets for "becoming carbon negative", not residences trying to do things cost-effectively to lower their electric bills.
My system is 5kWp/8kWh @11.500€ three years ago, it would be now a bit different (400V batteries instead of 48V and a hybrid inverter instead of a p.v. string inverter AC coupled with a battery inverter) @~ the same price due to a single inverter and slightly cheaper p.v. modules (@~100€ for a 415Wp). If done by third parties the cheapest proposal back than was ~30.000€. At this prices given current electricity prices and local grid stability it's a nonsense, it's even cheaper a diesel generator.
I know prices in China are FAR lowers, and I've read also on far lower Thailand prices, but compared to local cost of life I can't quantify how much.
This is what I’m planning to buy, but you know something better I’d love to take a look. https://signaturesolar.com/eg4-lifepower4-lithium-battery-48...
I have always had good experiences with signature solar. My inverters are EG4 and I am very happy with their product after trying A LOT of others. I think the primary reasons for the price difference is that you are purchasing US inventory (it's already here), it's preassembled and warrantied as a unit, they provide pretty decent support and their battery packs use 100ah cells instead of 280ah+ cells. So you are buying ~3x as many BMSs, connecting cable ($$$$) and cases for the same power.
Their rackable units are not light but can be moved by a capable person without too much fuss. A fully loaded 280ah unit in it's case is over 250lb so you really need a lift cart or such. The 280ah units and now maybe 320ah are more economical.
It'd be great to replace it with an LFP battery.
Will Prowse on youtube I think has some videos comparing and contrasting the different units for this purpose.
That said, something I can confirm works on that front is getting one of those power banks, plugging the UPS in, and then plugging whatever into the UPS.
I had several days of uptime on Starlink that way, running it 10 hrs or so at a time on a battery bank, the remainder on a cheap generator.
Building a big 14s 14kWh serial pack is really not hard, albeit those small hardware costs (bus bars) can add up. Most people don't need that much energy, probably, but these cells are just epic, maybe go 24v if you want less. 8k cycle life makes them good for a much much much longer time than most cells.
https://geizhals.de/?cat=bmseswresp&sort=t&hloc=at&hloc=de&v...
Instead, a simple approach is to download the daily power consumption for a year and size the battery for about your 80th-90th percentile consumption. You tend to find the sizing is not that sensitive to whether you go for 80th or 90th percentile, and in any case the batteries come in standard sizes.
If you've sized your battery system economically, it should be empty a good proportion of the time, but that just doesn't "feel right" to consumers.
* Yes I mean frequency not probability but I didn't want to cause confusion with electrical frequency
Although I suppose it is cheaper to oversize solar and not the battery, but that's usually already maxed out and limited by roof space. Maybe a small wind turbine to compensate for stormy days...
I think they're talking about the situation where you're still connected to the grid, in which case you don't need to handle the backup capacity.
It's part of a house. Of course it's not an impulse buy. That's not a useful basis for comparison.
Sorry what? Currently I'm happy to buy 5 kWh units for €1300.
It feels a lot like gambling. You might get one that works for a thousand cycles without issues. You might get one that fails after a week. You might be able to get a warranty replacement, or you might spend hours every week trying to make progress on a warranty claim without any luck.
You’re right that there’s a lot of opportunity if you’re willing to buy used panels, Chinese batteries, and do all of your own work. However, the cost of equipment is falling while the costs of labor are rising, which is why professionally installed systems are still expensive.
The failures often came from BMS or other parts, too. There’s a lot of focus on the cells, but people are buying whole packs with a BMS.
This article blurs the lines between the cells and battery system, too.
I’m talking about assembling your own multi-kwh lithium battery assemblies (pre-BMS even).
One wrong poke with a screwdriver, and all sorts of entertainment is likely to ensue eh?
And they’re big enough, no portable fire extinguisher is going to make a dent either.
I'm not sure where you're jamming the screwdriver, but certainly any wrenches/tools you use should be insulated if you're dealing with very high current and/or high voltage. Enclosures, insulated wires, conduits, terminal covers should be used to avoid short circuits. Also proper earthing and circuit isolation with RCBOs to protect from electric shock and overcurrents frying the wires/you, all which should be switched to the off position when you're poking your screwdriver, eh? ;)
> And they’re big enough, no portable fire extinguisher is going to make a dent either.
If you aren't doing basic safety things and somehow manage thermal runaway on LiFePo4 (pretty hard), you're probably going to melt some copper. Probably best not to put your battery assembly near flammable things, unless you want to see the world burn like this guy (though at low voltage/high current)
Where I live many people DIY as a great many people have mad skills (lots of FiFo workers making a good living from O&G installions and big mining projects).
They build their own houses, their own planes, off grid power systems, water proof EV's to drive across harbour floors, etc.
If you've got a big (shipping container sized) battery pack you need a big thermal blanket to cut off the oxygen or a wide enough fire break about it.
Speaking of DIY home builds, here's a good use of black builders plastic: https://www.youtube.com/watch?v=1ILbQHnHPnY
I’m talking about assembling a bomb.
A 5kwh battery contains about 18MJ of energy, equivalent to 4.3KG of TNT. Short that out or puncture on of its component pouches, and it’s going to be very dramatic.
One of them requires a different degree of care than the other.
Most people, full stop, don't build houses, metal work shops, treat their own sewerage, build their own power systems, etc.
So "average" people just don't start fires or set off bombs because they're not doing anything that dangerous.
Of the people that do, say, build their own glass furnaces, annealing ovens, laying out gas lines and installing small truck sized propane tanks with more energy than a 5kwh battery .. easily less than half, well below the "average" number of people that do such things, have accidents.
Sure, some people do watch Forged in Fire and have a go at knife making in a home built furnace, and then set fire to their barn | house | shed.
Most people don't try, and of those that do have a go most of them don't screw it up.
The point being, this:
> Also prone to average people setting themselves or their houses on fire, eh?
is just silly.
Average people don't attempt this, and of the people that do attempt such things most don't cock it up.
Perhaps your personal experience differs.
Maybe you can't dig your own septic system and fit it out without shit running back into your house.
So seriously, WTF?
You’re doing on this weird rant, when I literally just said average people shouldn’t be assembling their own multi-kWh lithium battery packs unless they want to burn their houses down.
Which is, indeed, good advice. And pertinent to the discussion.
Where this bizarre tangent you keep going off on is not.
Consider that I explicitly stated:
* They build their own ... planes
* They build their own ... off grid power system(s)
* They ... water proof EV's to drive across harbour floors
and you responded that "No, you’re talking about building structures. I’m talking about assembling a bomb."
Let me remind you that aircraft are bombs, off grid power systems are bombs, water proof EV's with battery packs large enough to drive 7 km's underwater have the same issues you're talking about.
You apparently didn't pause to read the content of my comment before launching into a "Yes, but ..."
I've already linked to locally built ground effect plane (with builders plastic for wings), here's a locally built EV: https://www.abc.net.au/news/2023-07-30/nt-world-record-darwi...
Average people are quite capable of doing extraordinary things and not burning down their houses - you just have a low opinion of "average".
Idiots that can't read manuals and installation guides should avoid house grade battery packs, sure.
If you counted them and put them on a distribution, how far off the bell curve do you think they'd be?
In fact, they seem rather extraordinary. If they seem average to you, I'd argue your sense of average is rather extraordinary too.
Average goofs shouldn't be assembling their own solar system and battery setups. Even an average person will apprise themselves of the know-how to proceed safely, and are legally obliged to do so. If average person is not interested in doing that, they'll call on a professional, and in some places, that is the only legal option. But perhaps there are contradictory stats out there to show that there's a real widespread phenomenon of well-meaning Average Joes and Janes that are burning down houses with DIY batteries.
This isn’t running a nuclear reactor it’s following some basic rules and common sense.
Lifepo4 is much more stable than you seem to think.
To me, the main thing is observability. Too many people trust their systems. We need to see how things are going. As the voltage converges to peak, we should be seeing the amps level out.
We can't just trust the machines, ever. We need to be observant. Ultimately I think we'd be able to review & get rid of bad equipment more effectively, but we should be in tune with what these systems are doing, should be aware that - oh hell - we are at peak voltage and still pushing power in, and we need to stop. These systems need to report what they are doing. Being blind consumers makes the economic system weaker; these systems should all report what they are doing.
I'm probably not the only one wondering: does ordering from these Chinese suppliers require reaching out to them over email? I looked at both websites, and while Seplos asks to write in, CATL doesn't even have battery listings or sales contact information.
I'd love to order LiFePo4 batteries to put in some old UPSes of mine.
EVE cells are very famous in the DIY scene, you can get them via Alibaba/Aliexpress, or if you're in Europe from nkon.nl, they have a very good reputation.
From the same suppliers sodium batteries are currently $130/kwh and about 26% less efficient in the same form factor. I look forward to this changing.
Due to rising power costs I moved one of my homes completely to solar and battery (lifepo4) and haven't had any problems. I can't imagine ever going back to the power company. Panels have gotten to the point of being ridiculously cheap. I have a lot of space. I purchased pallets of used panels for more or less the cost of transportation ($34 per panel 270w). They produce about 85% of their nominal rating.
I mention this because other comments mention costs that are much much higher.