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Even today the cost of installing solar is dominated by the labor costs, not the panel costs. The panel costs have been collapsing for years now, but full system costs have been steady or even rising.

Some of this is people (usually required to by the installers) choosing expensive solutions like microinverters or optimizers that add a high fixed cost to each panel, even though both technologies offer very little utility to the customer. The old talks about how one shaded panel would take an entire array out are out of date and just plain wrong these days. The other is that some of the costs like permitting and interconnection are just as hard or even harder as they always were, especially as power companies get nervous about the number of people installing solar panels.

I’m not sure I’d say dominated (PV is still 40-60% of the installed cost of a utility scale plant), but your def on that labor, power electronics etc. have eaten much of the gains of cheaper/efficient PV

To be clear I was talking about rooftop solar.

Why when it's such a small part of the market?

Depends which economy you're in. Australia domestic PV is a significant component of electricity supply with disruptive qualities.

Which is kind of bizarre actually - Australia has tons of land with good insolation, utility scale PV should be an easy sell?

>expensive solutions like microinverters

Enphase IQ7-60 is $85 on Amazon right now.

Adding $85 to each $250 panel is a significant cost increase.

> choosing expensive solutions like microinverters [...] that add a high fixed cost to each panel, even though both technologies offer very little utility to the customer.

I have to disagree with you there... they're not that expensive, and they eliminate the most common single point of failure in the system.

When I installed mine last year, I got quotes from every major supplier: I paid a roughly 10% premium for panels with microinverters over a traditional system.

We're talking about extending the time it takes for panels that will work for 20+ years to pay for themselves by a few months, in exchange for a massive increase in redundancy: that was an obvious decision from my point of view.

Why would net metering go away? With distributed production and net metering a power company becomes an electricity broker instead of sole producer.

Because the price is wrong.

Power companies already buy much of their electricity from independent power generators. However, for the economics to work, producer prices need to be lower than retail prices. These prices change throughout the day, based on demand.

Net metering results in people getting paid the retail price instead of the producer price.

Why wouldn't the power company just reduce the price they will purchase power at? Make profit on the spread like every other market. There will still be people that have property where they can produce an excess of power they can sell.

This is what they’ll do. But that’s simply not what net-metering means. Net-metering means (essentially) buying at the same price that the utility sells.

That does make sense, but then it’s not net metering anymore and would require a smarter meter. It’s also less attractive to homeowners because they get paid a lot less. (Prices are low when the sun is shining due to competition from utility-scale solar.) Charging batteries starts looking like a better alternative.

A decentralized power system is going to have a lot of battery backup and that might even be more important than the solar panels?

Because they have signed 40 year contracts so that the people that built the power plant could get financing

I've been wondering about the medium-to-long-term outlook in this respect, and your summation of the numbers is very helpful.

> Electricity during the daytime will be free

> Panels will be cheap as dirt

If you don’t consider the capital of a panel then sure free / cheap as dirt.

Then the sun goes down and the wind doesn’t happen to blow, so you fire up your gas turbine.

> If you don’t consider the capital of a panel then sure free / cheap as dirt.

That's what I meant, the capital cost is already so low that you could use them as fence panels. They will only get lower with the looming supply glut.

Look at this monocrystaline (higher eff) panel in china: 15 cents per watt. There are cheaper ones too: https://www.alibaba.com/product-detail/Haitai-Solar-Panel-Pr...

A 400W panel will cost 60 dollars and has a size of 1.8mx1.8m. Per square meter that is $18.52

A generic plastic fence panel from lowe's 6ft by 8ft costs $120 https://www.lowes.com/pd/Freedom-Actual-6-ft-x-7-82-ft-Ready...

price per square meter: $26.87

Plus inverter costs, plus interconnection costs, plus mounting hardware, plus permitting costs, plus installation labor costs, plus disconnect hardware, etc...

You're glossing over the inherent danger of solar panels in that they are relatively high voltage devices that can't be turned off easily. This means they get saddled with expensive safety regulations. The glorious utopia where you buy a pallet of the things from Wal*Mart with your pocket change and stick them everywhere the sun shines runs into some logistical hurdles.

This is blown out of proportion in the US. EU has stronger laws for environment, worker protection, historical buildings protections, you name it. Yet they can easily install solar under 1 dollar per KWh. This is a self inflicted problem created in the US, and the solar roofs became a scam. For a 9KW system, installers can pay 2500 to the sellers/marketers. That is MORE than the cost of panels, this should tell you everything you need to know https://www.quora.com/What-are-commissions-like-for-a-solar-...

> they are relatively high voltage devices

On the contrary, they are low voltage (12V), which makes them more dangerous (because you need higher amps to carry the same amount of energy). To make them safe, you can install inverters closer to the panel, to raise the voltage to 110 or 220, making them much much safer.

> The glorious utopia where you buy a pallet of the things from Wal*Mart with your pocket change and stick them everywhere the sun shines runs into some logistical hurdles.

That can work if you install them as fences, or just on the ground in general. If you install them on rooftops then yeah, you need some serious consideration. The installations are still grossly overpriced, if both EU and Australia can do it under 1USD per Watt, so can the US.

> On the contrary, they are low voltage (12V), which makes them more dangerous (because you need higher amps to carry the same amount of energy). To make them safe, you can install inverters closer to the panel, to raise the voltage to 110 or 220, making them much much safer.

Lets check a random common panel.

https://www.solar-electric.com/rec-solar-rec400aa-pure-alpha...

Voc: 48.8 Volts

And the original post was talking about cheap installs, so you would string several together to put it on an inverter. You hit high voltages very quickly. Even just 4 panels and you're up to almost 200V at full sun. It's more typical to put 8-12 panels on a string. The voltages hit dangerous levels very quickly.

Again, the dangerous part is the intensity, the amps. Look at your panel in the link, it's at more than 9 amps. If you put them in parallel, you will keep the low voltage, but quickly rise the amps, if you have 5 panels in parallel you are at 45 amps!! That can cause the fires, not the voltage.

You want to tie them in series first, to increase the voltage and keep the amps as low as possible. 110V or 220V are not dangerous voltages, that's why houses are wired at these higher volts. People all over the world handle cables carrying 220V with very few issues. If you wired the house at 12V-48V, some wire in the wall would catch on fire every-time you wanted to toast a slice of bread, lol.

Solar panels are wired in series.

You just can't admit being wrong, can you?

They are typically first wired in series to increase the voltage as early as possible, to make them safer. If you were to wire them in parallel you would keep a low voltage and increase the amperage, which would make their wires glow like Christmas lights.

That's the whole reason why they started selling micro-inverters that go on each panel: to increase the voltage and decrease amps before even leaving the panel area, to make them safer.

Look at a typical micro-inverter: input is up to 50 volts, 10 amps. Output is 240 volts, 1 amp. https://solartown.com/solar-products/enphase-iq8-microinvert...

For panels, the voltage is not dangerous part, the intensity is.

You aren't going to achieve your goal of ultra-cheap panels everywhere if you're sticking expensive microinverters on each one. It's weird that you say "I'm wrong" then laboriously explain to me how I was right. The panels are wired in series. The voltages are up in the 100s, which will easily overcome the resistance of your skin.

If they were actually 12v they would be safer. You could handle them with dry skin. It's the same reason people aren't electrocuted while working on cars. The danger would be starting fires as you noted.

Anyway, in the real world when you have panels wired in series you typically need to shield the connection wires in conduit because both the voltage and amperage reach dangerous levels and you can start fires or kill people if they try to handle the wire, and you can't easily turn them off. This is part of the expense of installing solar panels that you can't really avoid. You will always need someone who knows what they are doing to handle the electrical part or you will kill people.

It's also DC - arcs won't self extinguish like AC will. Modern charger/inverters are trending towards nominal 1kv voltages for the individual panel strings too which is pretty impressive. 20amps at 1kv is 20kw!

Your math is off a bit. The panel you linked is 1.722m by 1.134m, or $34 per square meter. It's wild that it's in the same ballpark as a fence panel, though

uhh, you're right. I took their first listed dimensions, but if you look at the specs, it's your size. Anyway, same ballpark. I was actually considering using some second hand panels to build a fence, that's how I know.

With battery prices like this, and days to a week of a household's electricity needs parked in the garage?

https://news.ycombinator.com/item?id=38304405

Add in the large number of storage options that are coming to market besides lithium ion, from sodium to iron to straight up thermal storage, and we may still have gas turbines on the grid in 20 years but it's unlikely they will generate more than a few percent of a year's electricity.

We are seeing the first disruption of the electricity industry in a loooong time and it's going to upset all other energy processes too, as electrical sources of process heat become cheaper than burning gas or anything else.

Looking at where prices are today misses the picture, look at where they will be in five years or ten years in order to understand our future.