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Sort of true. It is indeed the case that, at least in the US, the cost of the cells is a minor part of the cost of a rooftop solar array. You’re missing one detail, though: a lot of the costs you’re describing scale with the area of the array — the costs of mounting, wiring, sealing roof penetrations, shipping, physically hauling the panels to the roof, etc. are all related to the number and size of the panels. If you can shrink the array by a factor of 3, it makes a big difference.

I’ve read that the economics may already be close to favoring multi-junction cells for this reason, and they’re nowhere near 90% efficient, nor are they cheap.

I did an analysis of coats for residential roof top installations in Europe for my Master Thesis. Overe here around 30 to 35% of costs are the panels. Still the most expensive part but nowhere near the 60 to 70% it used to be. Panels really turned into a commodity.

What struck me is that nobody, not even Solar City and others, looked at the logistics side of things. It seemed to me that eveeybody came up with elaborate and capoztal intensive ways to sell to the people with the smallest customer Life-Time value in the whole value chain. Putting sophisticated logistics in place to cut costs (my assumption was that by doing that the solar panel cost could be reduced by around 15-20%) and selling to installers would have been the better way to go.

So I second you and the OP, it is no ponger about physics (with the exception of large power plants) and more about people and how you get solar on said people's roofs.

Is your thesis in English and avalaible online?

German, unfortunately I couldn't convince my Prof to accept it in English. In case you're interested and not under time pressure I can translate it or part of it. Always happy to share stuff like that. Just shoot me a mail. hef19898 (at) gmail.com

Sorry for the long delay, but would encourage you to at least translate the key parts into English.

Started already and managed to get to page 12 of 78 when the people realized at work that Christmas is, surprise, again on Dec. 24th. I totally forget that I wrote that many words... ;-)

Plug and Play Solar is one way to dramatically lower soft costs of residential pv installs. Fraunhofer is working on this [1] and there are already other 3rd party products on the market.

[1] https://www.cse.fraunhofer.org/pnp

>other costs that are already beginning to dominate

Which is an argument for trying to make cells more efficient like the ones in the article apparently looking at 43-90% as against something like 18% for typical cell. If most of your costs are installing etc then those can remain the same while you get twice the output.

> Or, the cheesy TED talk clincher would be: the next big solution isn't always about electrons, sometimes it's about people.

An even cheesier TED talk clincher would be:

> the next big solution isn't always about electrons, sometimes it's about elections.

Honest question: do you think residential / small scale commercial solar is the future? As an outsider it seems like utility companies are best placed to deploy solar at large scale in the right locations, bypassing customer acquisition costs.

Here in California, PG&E offers the "solar choice" program where I pay extra to have 100% of my electricity generated from solar. This cost $6.50 of my $82 electric bill last month. (Yes I know electricity is fungible.)

That's a tough question.

Distributed production offers some huge advantages, but in the nrel study above you'll find that utility scale is strictly more efficient.

I think Hawaii is a good case study. Customers are generally frustrated with the power company's poor reliability and high rates. Rooftop solar offers a substitute for what has traditionally been a protected monopoly, and there's abundant sun, so solar adoption there is crazy strong. HECO has generally fought to slow it down.

If utilities realize this threat, they'll become competitive on price and customer service. Reliability in some places.

If they do not understand this threat, then they will just try to lobby for more and more extensive penalties for those with rooftop solar who are still connecting to the grid. Like cable companies raising rates in response to the rise of Netflix.

The most extreme version of that would be the emergence of microgrids - cord cutting from utilities by entire subdivisions.

Microgrids are potentially really cool technology, but would require some pretty intense dysfunction to take off.

So while I hope utilities figure this out, regions will vary, and rooftops put a new sort of check on how bad utilities can get, even if they don't become ubiquitous. Rooftops will inevitably be the answer in some places, not all.

Oh and if you look country by country, to places where it has been harder to get a well financed responsible utility... Parts of Latin America or Africa could really be jump-started economically by rooftop solar.

Another issue is theft. I own a remote desert property in many ways ideal for solar, but the utility electric bill averages < $20/mo.

Nobody is going to try steal the hot copper wires connecting my house to the grid.

But where there's a substantial PV array on display, there's batteries and an expensive inverter nearby, and not much to prevent taking them.

Yours is a very unusual case. Most domestic solar installations are on roofs, so not likely to be stolen, and most homes' electricity bill is much higher than $20/mo.

I don't expect the panels to be the first things taken.

The battery bank and inverter however, which are easily put invisibly to use by anyone even your neighbor, are quite the prize.

I'm not sure it's all that unusual a case. Solar is especially relevant to remote off-grid homes. Unfortunately, these are also prime targets for theft as they're often left unattended for long periods with distant neighbors.

Denser populations have a grid, and can just have a large solar installation powering that grid on a large scale.

It's a problem. Solar puts expensive infrastructure on-site, it's a mini power station.

> I'm not sure it's all that unusual a case.

> Solar is especially relevant to remote off-grid homes. Unfortunately, these are also prime targets for theft as they're often left unattended for long periods with distant neighbors.

Remote off grid homes are a very unusual case. Not saying there is no demand from that segment, but even there is a higher rate of demand from it, it's a small segment of the market vs urban/suburban rooftop solar, and I wouldn't expect major manufacturers and installers to optimize for it.

> Denser populations have a grid, and can just have a large solar installation powering that grid on a large scale.

That's already happening today. However people choose to have rooftop domestic solar for many reasons ... to fix the long term cost of their electricity consumption, to offset peak power rates, etc.

> It's a problem. Solar puts expensive infrastructure on-site, it's a mini power station.

In situations where site security is a problem, presumably custom solutions can be put in place by installers to ensure security of the inverters and batteries. It may cost more, but that's sort of the price paid for owning property in a sparse, remote location.

Also in some parts of the world they will definitely steal your copper wires (out of the walls of your house if there isn't sufficient security!) But in those places your solar gear wouldn't last a week.

In the UK an acquaintance of mine has regular phone outages because the copper comms lines are pulled. They're shallow ditch laid; the thieves hook one end to a tow-hitch and drive, I gather.

I've heard about this happening, fortunately it's not that bad where my property is. Not yet anyways...

Are you seriously arguing deployment should cease because of a theft risk?

I don't doubt the theft risk exists. I'm asking if you are catastrophising to "..so we shouldn't do it" or just observing a downside risk component.

Nope, not at all, I wasn't aware I was engaged in an argument.

It just makes more sense in a lot of cases to let the utility provider convert to solar than turn your house into a power station you then have to secure accordingly and maintain.

I'm not interested in having to surround my property with barbed wire topped chain link fences, which is what you'll see around power stations for good reasons.

Mostly risk of death reasons. Solar and battery are not high on my list of lifestyle and risk components any more than a car parked outside or plants are.

Maybe you live in a much higher crime risk area. I know (for instance) honey hives in NZ are being predated by gangs so I can believe there are portable high theft risk things in rural settings. But I'm really unsure a Tesla battery rig is one.

I've had plants stolen. I still maintain my garden..

> I've had plants stolen. I still maintain my garden..

What a world it would be if independent solar power were the cost of a garden!

How much do you value your time? Gardens tend to be pretty expensive when you add up the hours for a decade or two!

Ah yes.. economic efficacy meets relaxation and hobby. You can't buy pre-read books quite the way flann O'Brien wrote about but it feels like we're close.

Having said which, close friends ran bespoke gardening for richer garden aesthetes.

Back to the lead topic. PV is worth doing but assess your theft and vandalism exposure in risk/cost benefit.

Data, please: how many documented cases of this type of theft actually exist? No offense, but it sounds like you live in the middle of nowhere and are slightly paranoid.

Rural theft is a big problem around here. Just a few months ago someone stole the entire generator at a tower site that is high up on top of Grey Butte, near Smith Rock in Redmond, Oregon. I picture a similar risk for solar panels.

Yes. Rural theft is a problem. Now, explain how society advances if we give in to crime and we stop investing in rural communities

>Nobody is going to try steal the hot copper wires connecting my house to the grid.

Especially considering the wires connecting your house to the grid are actually aluminum.

Is PV theft really a problem though? I mean they could sell them on ebay but AFAIK most thieves aren't just fencing everything on ebay. I can't imagine a pawn shop would give them much for it considering how hard it would be for the pawn shop to resell them. With copper and aluminum theft the thieves can just go down to the nearest scrapyard and get paid by the pound.

At some point, there has to be a standard to which roofs are built (including wiring and power ports) such that you can just buy shingles and put them in or replace from the inside. Just cut the middle men and installation costs.

I hate to be a bummer but based on the way the construction industry works, that's almost certainly not going to happen. For example, in the U.S. most plumbing jobs fall under a bevy of regulations and yet tasks as simple as changing a faucet can frequently lead to issues like unmatched pipe diameters or thead types. We've had 100 years to standardize that and it's still a mess. You literally can't even just go buy a garden hose and know for sure it's going to fit your exterior faucet.

Electrical is arguably the most regulated, standards based and straight forward aspect of construction and even that varies a great deal based on the electrician and equipment.

A rigorous standards based construction industry would be amazing. We could design electrical systems that could be installed by a novice with almost no risk of danger or failure. Homeowners could change luminares just plugging them in and attaching them to an electric box toolesly. We could have plug and play water appliances.

Damn it would be magical but again I'm fairly certain that's just not going to happen.

Edit: Above I indicated that the construction industry doesn't operate on "rigorous standards". That's not really true. There are actually very good science based standards for most construction tasks. It's more of a problem that the industry doesn't really focus on making future work on a structure low cost. And it makes very little effort to increase accessibility by creating more consumer facing equipment and tools.

This is, I assume, because standards and regulation are aimed more at safety than at ease of maintenance/modification?

The majority of construction regulations I've run into are relatively flexible. It's expensive but if you want to try out a new material or technique, the path to validating it and getting it approved is well defined. The problem is that few construction companies operate at that kind of scale and outside of churches, flagship venues (i.e. Disney hall), and palaces there just isn't enough money to develop new technologies.

That says a lot about the US. In Europe, you can buy only one type of garden hose because there is only one kind of port. If the EU would introduce a new standard to which roofs have to be built, then people will start using it within 3 years. And they will benefit a lot from that standard, so you will think twice before buying a new roof for 20k+ and not buy from the companies that keep to this standard. Also don’t underestimate the power of adapters.

I think you also conflate the way which something is built with the specification it is built against - like interfaces vs implementation details. If you tell companies to build a certain kind of roof, with ports and wiring, then they will not receive any money if they don’t meet your spec. They are free to use the kind of wood, nails, wires (as long as thick enough) that they like, and this is where they can compete against each other.

Perhaps the parent comment has had some bad luck, but I've lived in a half-dozen US states, and have never seen any garden hose tap that was different than the standard set in the 60s. FWIW. https://en.m.wikipedia.org/wiki/Garden_hose

Garden faucets in the U.S. can be 3/8, 1/2, 5/8 or 3/4 inches. They can have a course thread or if a backflow preventer is reuired in your muni, they have a fine thread.

I've seen hoses with all of those diameters, but they've all had the same standard fitting size at the ends. Same with the backflow preventers- all the normal course threads. Now I'm genuinely curious, what state are you in? (not being obstinate, I really am just curious!)

No offense taken. I'm in Western Washington state. The home I previously lived in had fine machine threads on the exterior faucet. I assume this was to prevent attachment of a hose without a vacuum breaker. Here's the item I had to purchase to attach a standard garden hose.

https://www.amazon.com/dp/B002OU6ZSA/ref=cm_sw_r_cp_apa_tbA-...

Now that I think about it though I believe you are correct about the diameter of the port being consistent. It is indoor plumbing valves that I've run into a variety of sizes of. 1/2" vs 3/8 compression.

Interesting. Thanks for answering!

This is not true. Although Gardena has a huge market penetration in the EU, it is not a EU standard.

There are other types, no EU involvement here ( yet ).

Did I say that garden faucets are standardized? Yeah you can get other sizes than the Gardena ones I guess, but those are more obscure. I think you will agree though that EU standards are usually followed.

Simply not true. In Poland we not only have two standards, they are also expressed in inches: 1/2 and 3/4.

Yes, but only two and they are a no-brainer because of adapters.

If you can design a roof from which a shingle can be replaced from the inside, the roof doesn't leak when exposed to wind-driven rain, the roof can hold your weight, and the cost isn't hilariously high, I'll be impressed.

Also, if you stick a power port on your roof and you live in an area with lots of lightning, I'll stay away from your house.

Basically every window is opened and can be replaced from the inside. How is that different?

Regarding lightning, IDK how the Tesla roof solved this, but they obviously did.

Have you ever seen a roof built? There’s a roof deck, and shingles of some sort are nailed in from above in a specific order. In many installations, there is a weatherproof barrier between the roof deck and the shingles. If you want to replace a single shingle in the middle, you do it carefully, and you may need a special fastener.

That’s how they are now built, yes. Cars looked very much different 100 years ago, too.

Yes, and also making that house, or land, or taxes produce 4x as much energy is categorically different form reducing the cost of existing 22%-efficiency panels by 75%.

That's because higher-energy-per-unit-area panels increases the efficiency of land use, which drives all the other costs you list: land acquisition, taxes, customer acquisition, etc.

Plus the environmental costs of creating and, at end of life, disposing of the arrays.

You’re a good thinker and writer. I’m definitely ready for your TED talk!

OK, can you just buy a solar heating panel? You and your best friend can install it...depending on location you can easily get hot water for 6-10 months a year. That's quite a savings. You don't have to solve everything today ;)

Solar heating panel? A bunch of wooden/plywood boxes, some glazing for them (can actually reuse thrown-away window panels), a bit of plumbing with PP pipe (ridiculously lego-like easy), some kind of top tank (a common steel drum?).

And some making sure the roof/attic floor doesn't collapse, which usually is not a problem.

This can be _build_from_scratch_ in a couple of weekends with a best friend.

But for the construction codes. And unions.

It's so low-tech, so I wonder why I haven't heard of 19th century installations. Me, I actuially built two in places where construction codes are not an issue. And have seen functioning installs dating from 1950s.

I don't think it even makes any sense to mass-produce heat boxes the way the solar-electric panels have to be. It all can be either made on site or included into the house design from start.

That's maybe why you can't buy solar heating off the shelf.

I don't agree simply because it is very common for diy solar water panel systems to leak all over the place. There at least needs to be prescriptive code to help reduce instances of crap work. But since it is a lot of pipe in a small footprint, it just makes sense to have it made in a factory with better quality control.

You and your best friend most likely can’t install it. You not only need building permits, you also typically need a licensed electrician to do the work. Doing it without a permit or properly credentialed installers risks sanction from the municipality as well as potential insurance consequences.

A 'solar heating panel' in most cases is a water tank exposed to the sun as much as possible painted in black. Or maybe put inside a black box. Not a lot of electricity work there.

It's not quite that simple. Flat plate collectors are roof components, and they have all the problems of roofing. Making them leakproof despite big thermal stresses takes some work. Brazed copper plumbing works. Plastics, not as well.[1]

You usually want a water tank to buffer the thing, so you can get hot water at night. Temperature will be all over the place without that. Giant hot water tanks in attics need extra structural support, which was a problem in Florida at one time.

There are some fancier setups that will work in cold weather. Some systems use antifreeze in the panels, and a heat exchanger.

[1] http://www.alternative-energy-tutorials.com/solar-hot-water/...

"Convincing someone to attach something to their house has significant costs. Like, "over $2000 per install" significant."

Not any more. We've got 50-state legal solar stuff where you just lay the panels out in the yard, literally plug them into your wall outlet, and every outlet on that circuit is energized. You can even leave it hooked to your power at night time, as the junction boxes have barrier rectifier diodes that prevent the panels from consuming power at night.

Install costs are becoming almost negligible due to advancing technology.

Cell efficiency is up there. Typical monocrystalline panels run 20+% now days (and look utterly gorgeous - https://imgur.com/a/sZGtYmB - picture from my job.)

Opportunity costs? Each cell runs on average $1.00 for most manufacturers, so you just need to shop around. A typical 60-cell panel at 300W runs about $150-200.

Most of your concerns have not been concerns for about 5 years.