> This incredible pace of solar cost decline, with average prices in sunny parts of the world down to a penny or two by 2030 or 2035, is just remarkable. Building new solar would routinely be cheaper than operating already built fossil fuel plants, even in the world of ultra-cheap natural gas we live in now. This is what I’ve called the third phase of clean energy, where building new clean energy is cheaper than keeping fossil fuel plants running. Even in places like Northern Europe, by the later 2030s we’d see solar costs below the operating cost of fossil fuels, providing cheap electricity in summer months with their very long days in the high latitudes. These prices would be disruptive to a large fraction of already operating fossil fuel power plants – particularly coal power plants, that are far less able to ramp their power flexibly...
I predict a lot of fossil plants will convert to simply providing inertia for grid stabilisation and charge for the service. They won't burn anything any more and may even demolish their stacks and cooling towers. They will just keep their generators and turbines connected to the grid as a big virtual flywheel to dampen spikes in demand / supply and maintain the AC frequency within tolerance.
Inertia is slightly different to supply response and most inverters use grid coupling for frequency and phase synchronisation so are not suitable. The slow response of old plants is an asset in this case and only a problem if they are generating rather than just providing inertia, which is instant.
I focused on PV in college and the fact is solar is dirty and they haven't planned for end of life recycling. The potential is great and we will get there im sure, but I always thought it was irresponsible to subsidize and widely roll out especially the early stuff in the 90s that was very inefficient and filled with heavy metals and REE. I'm not up to date now but the only thing I can say is at least the efficiency is better even if they are using similarly toxic elements.
I'm probably much less well-informed than you, but I can't understand the arguments about the disposal of the panels at the end of their life. I throw away a wheelie-bin worth of trash every single week, that's 1040 wheelie bins over a 20-year panel lifetime, yet those panels are probably equivalent to about two wheelie bins. It's a microscopic volume. What is in solar panels that is such a disaster compared to household trash? In 20 years I also expect to go through ten phones and five computers (although admittedly I'd chuck them into the local electronics recycling bin).
Cadmium telluride is not the prefered technology for solar cells. Silicon is still the major player, and it is free of any pollutants. I checked the wikipedia page for "solar cell". Given these informations, any consumer or technologist can adopt solar without compromising on pollutants.
Batteries being made today will last 30 years, the first 15 will most likely be in a car and after that in a house battery. In 30 years we'll have drastically different ways of coping with waste so this concern about recycling is such a red herring.
If "recycling details" can be figured out later, then the same argument can be used to justify a massive investment in nuclear power, ie. 4th generation reactor, LFTR, you name it. It would generate more energy over its lifetime than PV ever would.
Nuclear has been around for 70 years and it is still extremely expensive to dissemble nuclear plants and dispose of their wastes. In fact, in the US we still don't have a permanent solution to nuclear waste storage. And a lot of the radioactive materials in them are vastly more dangerous than what you find in solar cells.
One key difference between solar and nuclear is that when solar goes wrong it goes wrong in a pretty small way.
Nuclear’s failure states are pretty awful, see Chernobyl, Fukushima for disasters, but just (something I learned as a kid) the Irish Sea being quite significantly radioactively polluted through normal operation of plants in the area.
The cost to dismantle millions, if not billions of tons of PV cell in 30 years is gonna be pretty higher, both in term of cost AND ecological impact than a localized power plant.
Also, Chernobyl is not a Gen4 reactor, the core design of RBMK reactor was highly unstable, and that the problem with anti-nuclear lobbying: we're stuck with old design we have since learned a lot from.
Assuming a 15W per sqft, and an average weight of 3lb per sqft, and assuming the output of a nuclear power plant is around 1GW, you'll need about 9e+4T of solar panel that you're gonna need to recycle over a lifespan of 40 years. Just the volume of this waste is 4.5e+3 truck load, and I'm not even getting started about recycling the silicon cells themselves (ie. very nasty chemicals), and all this is just about 1 equivalent plants. US wide, you'd probably need 200x this (to be significant), plus a 5x extra capacity to deal with fluctuation and non-peak production, that's another 3 order of magnitude. You also need to factor into account a redesign of the grid to accomodate with the mesh production, and the extra battery on each site.
Compare this to burying a few hundreds tons per year of low volume wastes for ~eternity in a cave in the middle of nowhere.
> Was Fukushima though?
No, Fukushima used BWR design from the 1060's, so geneneration 2.
Sorry, I checked and you are probably wrong, in the sense that silicon based solar panels (the vast majority) is free of heavy metals. The one you are maybe thinking about is cadmium telluride, and it's far from being widely adopted, precisely because of toxicity concerns.
Do solar panels eventually stop producing any power?
I have some second hand panels that are around 10 years old, I'm sure they are less efficient and I have had to replace diodes etc - but it seems to me that if you have lots of space (as we do in Aus) you could just keep adding new panels without getting rid of old ones
Solar panels you buy today just go down in efficiency - if you are installing them on say a house, they will continue producing good power output for the lifetime of the house (bar physical damage). Typically they will come with a waranty that after 25 years, they produce at least 80% of their rated output.
(You will probably need to replace the inverter during that time, but the panels will be fine)
Is there nasty heavy metals in current silicon panels? Have you more details? I'm (badly) surprised, I thought that would be merely the lead solder, solved by using lead-free one... Last I checked, I was under the impression that current technology was clean.
Efficiency improvements amplify cost reduction per kWh electricity: An ever growing share of PV system costs stems from every item that is not a a module (inverter, cables, labour etc). Modules are becoming cheaper faster than other components, so reducing module costs further has diminishing returns.
In contrast, taking your module efficiency from 20% to 21% increases electricity generation by 5% and thus reduces costs per kWh by 5%.
Anything using fossil energy also has such hidden issues.
And you have to consider the ecosystem:
- fossil fuel engines require much more maintenance than electrical engines, and now vehicules always embed heavy electronics anyway.
- fuel need to be transported at a heavy cost, which is now hidden by the massive demand. The day we use more solar than fossil, the whole fossil infra will suddenly feels very expensive
- most countries are not like the US and don't have oil on their soil. Countries don't like to be dependant on others for critical things. You may buy solar panels (or fuel engine) from a friendly country, but if things turn out badly, people can't cut sunlight from you one the initial setup is there.
Nothing is perfect of course, but I like the solar future we are hinted at.
I didn't suggest fossil-fuel-based energy production is superior.
Having said that - maintenance of cars using fossil fuels is not a relevant comparison, since we're talking about power plants.
Personally, I doubt that we can just -whoosh- swap the coal and petroleum for solar-based electricity and have our problems solved. It's likely that a lot of social effort to conserve more and waste less energy will be necessary to reach some sort of long-term-sustainable state of affairs.
So encasing the cells in glass stopped decomposition? There was no pressure buildup in the cells? No gasses released?
The test says it's 1800 hours of stressful conditions for the cells. Assuming 10h of sunlight per day, that's 180 days of stability. I guess time will tell how long they really last, but it's good news that they surpassed test requirements.
And having a 25% conversion rate baseline compared to a ~26% assumed max for silicon is also impressive. I wonder how much they can boost that.
If you're making something in a laboratory, it's not cheap, even if it could conceivably be cheap in mass production. Even once something is in mass production — like silicon PV has been for the last 40 years — it can take a long time to bring the cost down. Silicon PV cells have fallen in cost by a factor of 10 in the last 10 years, in part due to much higher volumes, in part because the production lines no longer need to be staffed by Ph.D.s. Who could have predicted in 1980 that that would take until 2015?
In a lab you can demonstrate how much material something uses, how long it lasts under given conditions, and, say, how sensitive it is to contamination. But you can't predict, you know, the late-oughties polysilicon price bubble, the ensuing long-term purchase agreements made by companies like Evergreen, and the subsequent polysilicon price collapse that sunk those companies. (I'm still not sure where modern PV cell companies source their silicon! Is it UMG?)
"How cheap?" is a question about international trade, mining, and management, not a question about materials science. Don't expect materials scientists to be able to answer it.
The raw materials for perovskite cells are cheap, but so are the raw materials for silicon cells. There won't be hard cost numbers on perovskite PV modules until they go into volume manufacturing. They won't go into volume manufacturing until they can be stabilized enough to last years in the field.
My personal guess is that single-junction perovskite cells will not ever overtake single-junction silicon cells for rooftop or utility scale solar. Single junction perovskite cells may be used in applications where light weight and flexibility are advantageous, like charging portable electronics, if they can be stabilized.
Perovskite cells may compete in rooftop/utility solar with conventional silicon when incorporated into tandem cell designs -- either perovskite on silicon or a stack of different perovskites with different band gaps. That gives them the potential to exceed conventional crystalline silicon module efficiency rather than merely play catch-up. The company that seems to be furthest along with this approach is Oxford PV, which is pursuing a perovskite/silicon tandem design:
If your goal is to power the car while driving, even 100% efficient solar cells wouldn't be enough, as there simply isn't enough surface area to gather enough energy to power a normal car doing normal driving. If your goal is to leave the car sitting charging in the sun all day, that's a bit more practical, but I believe there aren't yet any production vehicles like that yet: https://en.wikipedia.org/wiki/Solar_car
I think you meant to say 100-200 watts a square meter average output as a 300 watt solar panel isn't much larger than a square meter. Either way, you are right that it is unlikely that solar charging via a car roof will be anything aside from a backup/gimmick. But it is possible to get a good charge from solar panels on a rooftop with not a huge amount of panels.
OP is probably correct, maybe even high in their 10 to 20 W/m^2 estimated average output for car mounted PV systems.
Rooftop mounted, optimally oriented PV systems at Seattle latitude have an annual capacity factor of ~ 14%. That means a 1 kW system will average 140 W output over a year. That system has a module area of about 4-7 m^2, equivalent to the area available on a sedan.
On a car that has suboptimal module orientation and solar exposure, "power density" (RE: Smil) is really low.
I meant what I wrote. Sure you get 100W/m^2 when the sun is shining perpendicular to the surface, but divide by night, clouds, angles, dust/snow, latitude, air transmissiviness, line/battery/conversion loss, etc and you’re well under 20W long-term average.
It's probably worthwhile to put solar on cars, but it doesn't really do much to improve range.
A way to think of it is to imagine a gas-powered car with a gas tank that magically refilled at a rate of one gallon per week. That would be a great feature, but it wouldn't really change what you do with the car. It would mostly just mean spending less on gas over the lifetime of the car.
In the end, a car costs a lot of money and provides a couple square meters of usable space. Roofs of houses are a lot bigger and can supply the needs of a household, but if you're in the business of energy production and want to generate energy on the scale of a major power plant, it makes far more sense to use cheap land in sunny places away from cities.
There isn't enough surface area on vehicles for that to happen.
The world installed about 117 gigawatts (peak) of solar PV last year . If the average panel is 17% efficient that's more than 680 million square meters of panels being manufactured per year. World motor vehicle production in 2018 was 96 million . To put more solar panels on vehicles than we already put in fields and on rooftops, the average vehicle would need more than 7 square meters of surface covered with panels. That's neglecting that most vehicles are still internal combustion vehicles that couldn't do much with the electricity those panels would generate.
Just not enough room really. Maybe(read: no) you could get 5m^2 of panels on a car. With 100% efficient panels the energy would be 5 * 1000 W m^2 = 5000 watts which is about 7 horse power.
That is a bit below what a very aerodynamic car needs to maintain highway speed so sort of relevant from a range extension perspective but 100% efficient panels and 5m^2 being fully illuminated at once are not very realistic assumptions.
I could see electric trucks(non commuting) + tiny home on wheel with big arrays potentially being viable though. That + starlink would make a pretty cool working remote combo.
When we kitted our boat with solar panels the cheapest part of the entire system were the panels, ~$1/W. Half of the budget went into mounting and the fabrication of the mounting hardware and 1/3, or the remainder, went to wiring and controllers. This nearly lines up with domestic solar. 1/3 to panles, 1/3 to frames and mounting, and 1/3 towards electrical.
Panels at 2% efficiency would be wildly uneconomical at practical any price.
> Panels at 2% efficiency would be wildly uneconomical at practical any price.
I guarantee that is wrong, if the price got low enough it would be economical. Wikipedia suggests to me  plants operate at 3-6%, and plants are extremely economical. Even starving African children can afford access to plants. If solar panels were as cheap and easy to produce/distribute as plants but could be plugged in to a grid then 2% efficiency would be wildly economical - it would be the greatest energy revolution in human history.
Lots to unpack here - is there a more straightforward way to word your argument here? To put GP's post in terms of yours, the planters and water cost much more than the plant, so even if "starving kids in Africa can afford access to plants", it doesn't mean greenhouses are free
It isn't an analogy. Plants are literal solar systems. The only reasons they can't be plugged into the grid is they deal with energy chemically instead of electrically.
It doesn't require that much imagination to say that solar cells might one day be work in an extremely similar fashion to plants. Not likely, but not an outrageous thought.
Nature has produced a cheaper, more ubiquitous and more self-replicating solar system using efficiencies in the 5% range with a theoretical cap of 11%. That suggests we don't need 25% efficiency to accomplish amazing things. It isn't a critical metric.
I think most biofuel is currently more expensive because it is diverting high input monoculture crops that are typically grown for feed like say corn ethanol or soybean oil. I believe ethanol from sugar cane in Brazil was cheap but only because the humans laboring to harvest it and process it were paid very little. But yeah the current choice of using industrially farmed high input crops to source biofuel does make it expensive. I think ultimately heavily refined energy dense fuel does require lots of time or energy input to produce.
The energy that a plant captures doesn't go in to biofuels; it goes into growing the plant. Pushing roots through rock, extracting minerals from the earth or whatever it is plants do. Pushing water from the soil up trunks or through stems.
The biofuel is burning what amounts to the plant's surplus energy that it wasn't using for anything, and recovering some of the energy that went growing the mass of the plant. It isn't comparable.
The point here is plants are covered with tiny green solar panels that are grossly inefficient compared to what humans produce. However, they are beyond cheap to produce (in fact they grow themselves) and suggest that we are not even close to pushing the limits on what we can do with solar energy design wise.
Efficiency of the solar panels really isn't all that important compared to making something with the flexibility and weight of a leaf. Comparing efficiency between solar panels is a waste of time outside the research community; all that matters is total cost to install vs. watts produced.
At 2% efficient and 0 cost they would probably be more expensive than current when looking at total installed cost for commercial/residential, maybe even utility.
You can see even at utility scale the panel prices are generally less than 50%. I think 2018 increase was tariff related. Been out of the industry ~5 years so don't follow stuff that closely. Many of the other costs are basically a multiple of # of panels which would be 10x at 2% efficiency.
I did say fabricate and install you'll notice. If they came up with something really light and cheap to produce installation costs would plummet. Compare the cost of installing windows to installing solar panels - windows don't even have a rate of return but everyone has windows. It is a no-brainer to install windows. Solar panels are not a no brainer decision (yet, hopefully).
And that was the point - weight and difficulty of transporting the final system is a very important variable. Probably more important than efficiency when orders of magnitude are concerned. From a 25% base efficiency can double and double then it stops improving. Weights and installation costs due to the panel technology can halve and halve and halve and so on - and each halving reduces the cost of transporting the panels. There are more gains to be made there. It would be worth trading efficiency away to make big gains there.
I think what's happening is bare processed silicon wafers are cheap enough that that other costs of a panel are starting to dominate. That pushes you towards using high efficiency cells in order to reduce number of panels needed.
I think Perovskites are interesting because they are cheap and can get you 25% efficiency in a single layer cell.