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I had serious misgivings when Tesla/SolarCity announced a switch of focus to building-integrated PV. Historically, BIPV is where a PV technology goes to die aft
by philipkglass 10y ago
I had serious misgivings when Tesla/SolarCity announced a switch of focus to building-integrated PV. Historically, BIPV is where a PV technology goes to die after it's failed to compete against incumbent module designs.
But these have far better aesthetics than previous BIPV efforts. They look better individually and they aren't clumped in one odd shiny patch on the roof like past BIPV. Search for images of solar shingles and you'll see what I mean about previous attempts.
On Friday's thread someone here mentioned the 30% tax credit for solar installations. That made the financial proposition click for me. If the whole roof qualifies as a solar system, that's probably how they can make it financially attractive. Unlike past module-atop-roof or even patch-of-roof-BIPV offerings, you'd be able to get a tax credit for the whole shebang. Add the usual solar motivation of reducing retail electricity purchases, plus getting a roof that's more durable and attractive than the typical asphalt or wood shingles of American roofs, and it looks like Tesla/SC may have a better offering than competitors for new home builds in areas with lots of sun and expensive electricity. It wouldn't take a whole lot of builds per year to soak up all the capacity of their Buffalo factory.
Just a few days ago I was saying that I couldn't see how any of the solar installation or manufacturing companies were going to build decent, defensible profit margins because panels and installation services are so commoditized. This could be the advantage that was missing: assuming decent patent coverage, SC will be able to have a monopoly on these modules and their installation for a long time to come.
- Jugurtha 10y ago>Search for images of solar shingles and you'll see what I mean about previous attempts. The first 9 images Google returned in the top 2 rows for "solar shingles" have 2 pictures from Tesla/SC's presentation. (~22%). The 3 top rows (13 images) contain 3 images from the presentation (~23%). It looks like you're right about the change to come.
- Maken 10y agoI just made the same search, and indeed several of the top images are from the Tesla presentation. However, what have surprised me more is discovering that"solar shingles" have been a thing for so much time, and there are already some quite decent looking models, even curved ones. Of course, I have never heard about it. Tesla marketing is really far ahead of everyone else.
- Jugurtha 10y agoI've been interested in solar since I saw a solar powered Casio watch as a kid but haven't kept up with the technology. The panels are ugly and having to add a panel to get solar energy is clunky. I want to believe, looking at all the devices a smartphone has replaced, that one day this won't be the case.. Then I look at trees, devices that had millions of years to improve solar energy conversion but still rely on solar panels and it calms my passions. But maybe, we could evolve and plug the Calvin cycle into the Krebs cycle! Our skin has a surface of about 2m². We could go solar (would have to walk naked) or cover up and eat food. Maybe will come a time where people who rely on food are the pariahs of society. The "Covered Ones". I suppose one great revolution would be finding a way to add the photovoltaic effect to materials (paints, fabrics, plastics, etc) or make these materials with the effect embedded. I think there are flexible panels that are being made, but even those look weird. I want it to be a materials property, similar to the antimicrobial property of copper alloys. The irritating thing with microelectronics is that the die is minuscule and beautiful, but then you have to add pins and pads and a package. Dust is also a problem. It's amazing that a thin film of dust you couldn't even notice without a finger swipe could have such an impact. And then there's the connection between transistors that has to be a certain way. What would be great would be for the transistor to become a molecule or be packaged in a molecule. Water is water and no matter the phase, the molecules adapt to find their place with respect to each other. The layout needs to be independent of humans' will and answer only to the laws of nature (you don't worry about each molecule when you apply a coat of paint).
- kayge 10y agoI had much better luck seeing the "previous attempts" by opening up a private/incognito window, and using this as the full search term: solar shingles -tesla YMMV :)
- Jugurtha 10y agoHere's what Google Trends returns for "solar shingles" for the past 5 years. https://www.google.com/trends/explore?q=solar%20shingles https://www.google.com/trends/explore?q=solar%20shingles
- 31reasons 10y ago>>SC will be able to have a monopoly on these modules and their installation for a long time to come Is that really Elon Musk wants, monopoly ?
- tdb7893 10y agoMonopolies make money and you need money to do cool stuff
- zzguy 10y agoAgreed, look at Google. Monopoly on search, and has definitely built some cool stuff.
- deleted 10y ago[deleted]
- tdb7893 10y agoYeah people seem to disagree but I find it weird to see Silicon Valley seems to dislike monopolies but constantly builds them. Google, Amazon, Facebook, Microsoft, Intel, really just name any big tech companies and they probably have a monpoly or something very close to one on something. There's no problem with it and the only real way to get the returns that people expect is to create a monopoly somewhere.
- Tinyyy 10y agoIt’s not weird actually. Monopolies are bad for people who want to create monopolies.
- ygjb 10y agoMaybe, but one important factor is that having a patent-protected lock-in on a market that has a great deal of potential will certainly make his investors happier.
- philipkglass 10y ago
- deleted 10y ago[deleted]
- ChuckMcM 10y agoI think this is exactly right. There is some fudging with the cost (this seems to be a common theme with Elon) by pre-including savings and rebates Etc, but the fact is this makes a solar roof something different than a set of panels across an existing roof. The durability question, and the weight per sq foot will be interesting. That said, the combination of the PowerWall and the roof might actually make it more amenable for power companies since you could grid tie "for emergencies" but lower your total overall power budget and help avoid the evening surge (max grid usage in the Bay Area is about 5:30PM, solar is off-line and people are coming home from work, firing up appliances (like cooking dinner, getting a beer from the fridge which turns on the converter) environment systems (heating/cooling) are activating to bring the house to the 'occupied' temperature, Etc. If your house uses its PowerWall for all that energy you'll appear as a much smoother non-load on the grid.
- hinkley 10y agoTar shingles are pretty damned heavy. If you've never experienced it, try picking some up at your hardware store, they have a bit of a weigh budget to work with. And then if you want some sympathy for your roofers, imagine slinging a box of those while standing on a diagonal surface 20 feet in the air in the afternoon sun. Yikes. I'd almost worry more about about the size of the panels making installation problematic in a light to moderate wind, and having them sail off the roof into the neighbor's car.
- brownbat 10y agoSolar, surprisingly enough, has a higher death per kilowatt rate than nuclear, primarily because roofing work is so dangerous. Nowhere close to mining coal of course. http://www.forbes.com/sites/jamesconca/2012/06/10/energys-deathprint-a-price-always-paid/#41956adf49d2 http://www.forbes.com/sites/jamesconca/2012/06/10/energys-de...
- josinalvo 10y agoI've heard these numbers from Forbes come from a very pro-nuclear estimate. Does anyone more knowledgeable care to comment? What other estimates are there? How are they calculated?
- tajen 10y agoBut is it carbon-neutral now? Let's remind the whole picture here: We want to come back to global greenhouse gases emissions on 1990, because they were balanced by nature's absorption. It often happens that the cost of building solar panels, transporting them to the location, disposing them before their estimated time-to-live and getting rid of all their chemicals emit more carbon than we save by using electricity from the solar panels. Another bias is: By making energy cheaper, does it encourage the use of said energy, thereby offsetting the gains? "I've saved 20% of carbon emissions compared to having a petrol-based SUV" tells another story than "I don't have an SUV". Greenhouse gas ecology is hard. The only way to avoid doing those analysis would be to tax carbon emissions for the side effects they produce. Then we would be able to just by the cheapest, which would also be the most energy-efficient.
- philipkglass 10y ago1) Anthropogenic CO2 emission rates in 1990 were greater than natural sinks could offset. 2) Under any reasonable set of assumptions, rooftop solar PV has significantly lower emissions per kWh than the cleanest fossil sources. In 2014 the IPCC estimated a median value of 41 gCO2-e/kWh for rooftop PV generation vs. 490 for combined cycle natural gas generation. 3) Perhaps some of the CO2 avoidance will be squandered eventually as solar becomes cheaper, thereby encouraging use of more electricity, but so far total electricity use is uncorrelated or even anti-correlated with the presence of rooftop solar generation. "Rooftop solar" and "energy-thrifty building construction/operation" cluster together, so far, rather than displacing each other.
- redcap 10y ago2) Does that include the carbon cost of manufacturing, distributing and installing the tiles?
- philipkglass 10y agoYes. Hit up Google Scholar with "life cycle", "co2", and "photovoltaic" as terms if you want to understand in more detail. This report looks pretty good if you want just one document: https://www.nachhaltigwirtschaften.at/resources/iea_pdf/reports/iea_pvps_task12_report_2015_life_cycle_inventories_and_lc_assessments_of_pvs.pdf https://www.nachhaltigwirtschaften.at/resources/iea_pdf/repo... It's from the International Energy Agency and it is recent (which is important, because commercial PV technology is evolving rapidly).
- adriancooney 10y agoIts a dodgy business though converting your entire roof to this technology (in its first iteration too). What if a tile breaks? Whats the lifetime on each tile?
- Retric 10y agoThick glass tends to be fairly resilient so anything that's going to damage these would likely destroy normal tiles anyway. Depending on how modular these things are they should be able to deal with breaks without significant problem just run in parallel like the good Christmas lights which still work when one goes out.
- WalterBright 10y agoI had a ceramic roof once. Walking on the roof would break the tiles. It made it hard to do maintenance on anything up there. My preference these days would be for a metal roof.
- jdcarr 10y agoCorrugated iron is infamously loud in rain. What type of metal roof are you considering that wouldn't be such an earsore?
- foxylad 10y agoHere in NZ most roofs are corrugated iron, and people love the sound of rain on them. Different cultures... There is another good reason for our love affair with iron - we get a lot of earthquakes. An iron roof provides a lot of structural bracing, and it's negligible weight provides much less moment than slate or tile alternatives.
- WalterBright 10y agoCeramic roofs are very heavy, and as you say, they don't do so well in an earthquake. The house structure has to be designed to support it. Wood shingles rot, are slippery when moldy, are an ideal habitat for wasps, burn, and generate a demand for old growth cedar (i.e. not sustainable).
- swehner 10y agoThe 30% tax credit for solar installations may well be adjusted. These kinds of things are not so absolute.
- sbw 10y agoUnder a rare bipartisan deal at the end of last year, the solar investment tax credit remains at 30% through the end of 2019, then declines to 26% and 22% in 2020 and 2021 respectively. After that, there's no investment tax credit for residential solar. http://news.energysage.com/congress-extends-the-solar-tax-credit/ http://news.energysage.com/congress-extends-the-solar-tax-cr...
- RyanMcGreal 10y agoThere's another factor as well: for older houses, most building codes require that the roof be reinforced in order to hold the weight of a solar array on top of the shingles. But if the shingles themselves are solar panels, this issue goes away.