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China Installs Nearly 10 Gigawatts of Solar in First Quarter (cleantechnica.com)
191 points by jdc on April 26, 2018 | hide | past | favorite | 84 comments



The US used about 2 million GWh of electricity in 2015[1]. There are 8760 hours in a year. So the power usage averaged over the entire year is 243GW. The amount of solar the article is talking about could supply about 5% of that average usage. And that's just what was installed in three months.

If the rate of installation stayed the same then it would take five years for all US electricity needs to be met by solar.

[1] https://en.wikipedia.org/wiki/Energy_in_the_United_States#Co...


Perhaps I'm missing something but the capacity factor for solar tends to be around 20%, meaning that 10GW of nameplate capacity generates an average of closer to 2GW in practice. I didn't see it addressed in the article, so I'm assuming the number is nameplate capacity.


It's true solar capacity factor is between 10-25%, so nameplate isn't terribly useful. With that said, the rate of solar being installed isn't slowing down, and more fabs are coming online each year.

I would be shocked if there's any fossil fuel generation online in 10 years, 15 tops.

https://www.pv-tech.org/editors-blog/global-solar-pv-manufac...

https://www.pv-tech.org/editors-blog/planned-solar-manufactu...

https://www.power-technology.com/comment/global-pv-capacity-...


I wouldn't make predictions like that until there were similar investments into storage or international/continental transmission. It could be done, but we're not doing it.


Storage and transmission are both self-fulfilling prophecies based on market economics. If it's cheaper to store or transmit clean renewable power than it is to use expensive coal or nuclear plants, the investment will be made (I discount distributed/rooftop solar for this argument, but it is important to note that distributed solar reduces the need for transmission).

Transmission lines are currently being bid out and built to bring cheap East Texas and Oklahoma wind to load centers [1]. An enormous amount of lithium battery manufacturing capacity is coming online worldwide to satiate EV manufacturing requirements. Those facilities will also produce stationary storage.

[1] https://www.elp.com/articles/2018/02/miso-taking-proposals-f...


Certainly it will, but to reach the storage levels required we're going to need 10 more gigafactories for batteries alone. Any alternative storage tech (molten salt or whatever) is 10+ years away. Clever distributed solutions such as using EV car batteries will require massive renewals of smart grids (which will move glacially)

It's going to take more than 10-15 years. Way more. It'll take 10 years from the date that we see massive investments on the scale of the OP into storage as well as the panels.

I'd say optimistically, in 10 years we'll have enough PV installed that the problem of PV overproduction (and negative prices on the market) will finally be big enough that it will cause mass-adoption of storage to begin, which will then take another 10 years to get going.


I think I fall between the two extremes of the parent and grandparent comments.

I think there are at least 10 gigafactory scale battery plants in the process of being built, so that's a positive sign.

I also believe that EV batteries will benefit the grid with basically no added infrastructure. Let someone sign up for a special tariff that gives them cheap power at certain times and let the computer in the car decide when to start charging. Already happening today with dynamic info from the net on carbon intensity predictions.

Finally, overproduction of solar and wind are not problems in themselves, nor are negative prices a problem. People repeatedly stating they are a problem is a bigger problem for renewable energy than the so-called problem.

As you correctly go on to imply they are an opportunity for storage and demand response but the bottom line is that wasting energy is not s problem as long as the costs (financial and environmental) when divided over the energy that is used, is lower than the next best alternative.


The odds of having enough energy storage in place in 10 years to eliminate fossil fuel energy production approach zero. Solar and wind are great production methods, and are proving more and more econoimcal every month, but neither con produce energy on demand in all conditions.

Without a huge national grid to compensate for weather patterns (problematic due to transmission losses), or a massive increase in storage capacity and technology, we just can't eliminate fossil fuel energy.


Not to mention the millions of homes/buildings using fossil fuels (natural gas furnaces) for heat.


My understanding is that the high voltage transmissions have little resistance, and that the biggest problems with a national grid is not transmission loses but the cost of building thousands and thousands of miles of high voltage electrical wiring to connect existing subgrids together.

Do I have a misconception?


Adding wiring is fairly cheap per mile, connecting different electric networks via substations is the more expensive bit.

The larger issue is capacity needs to be used regularly to be cost effective. If you want to send 10GW for 24 hour a day or 15 minutes they both need the same infrastructure.


If we care about eliminating fossil fuel usage, we need the gradient in the renewable uptake to high enough to cause a catastrophic shock to the fossil fuel technology and delivery chain. If it is too low, it renewables will drive down the price of oil, causing a jevons paradox follow on effect, where the price of oil falls, but because the infra structure is already in place, it is easy to use (infra can be useable but decay over time). Worst possible outcome is that the oil supply redirects to the developing world and millions of lawn mower style engines are put into high utilization.

Fossil fuels need a total shock to the system to end their use, otherwise we will indeed burn everything that is in the ground.


Really? That's the worst possible outcome? I would have assumed that the worst possible outcome would be that the oil supply didn't redirect to the developing world and the developing world would be left with no cheap energy that they had the infrastructure to exploit at all.

Which would be a great way to ensure that it never reached "developed", although I suppose it would stop it from developing...


If markets would have developed the developing world, a resource rich paradise, they would have done so by now. Instead, they imperially marched in and stole everything they could for the benefit of their masters back home. Markets don't sell to poor people, they sell to middle-income and rich people. They steal from the poor to give to the rich. That's the whole idea.


I don't know if you'd noticed, but the developing world has actually gotten smaller. Take just one example: in 1957, South Korea had a lower per-capita GDP than Ghana, and no natural resources to speak of. And speaking of imperialism, the US and USSR throwing their weight around fighting proxy battles and ripping the top half of the country off hadn't exactly helped.

Now they're a trade and manufacturing powerhouse, and when South Korea blinks the entire world's supply of memory fluctuates.


Remember that one time where everybody always buys things from a market, regardless of whether you call their country “developed”? Remember how class has nothing to do with supply and demand? I do.

Perhaps it’s me, but ur comment’s anti-imperial skew makes me think you’ve gotten an imperial education.


>Worst possible outcome is that the oil supply redirects to the developing world and millions of lawn mower style engines are put into high utilization

This is exactly what will happen.

https://www.youtube.com/watch?time_continue=1&v=8PavA4rUypE


> I would be shocked if there's any fossil fuel generation online in 10 years, 15 tops.

What? Fossil fuel usage has increased not just in china but around the world.

https://en.wikipedia.org/wiki/File:Bp_world_energy_consumpti...

It's far more likely that solar will disappear than fossil fuel usage especially with china wanting to urbanize another 500 million people and India, ASEAN and Africa looking to industrialize.

> the rate of solar being installed isn't slowing down

It has slowed down tremendously. Seems like you haven't been paying attention, but the solar industry has collapsed around the world. Elon Musk even had to bail out Solar City.

What's with the ideologues. It's either the peak oil fanatics or the renewable evangelicals.

The only way we aren't using fossil fuels in 10 years is if civilization collapses.


Solar and oil (and natural gas) supply different markets and compete mostly at the margins.


When I say fossil fuel generation, that's peakers (single cycle natural gas or fuel oil/diesel/heavy oil) or baseload coal or natural gas.

Maybe I'm mistaken by what you said? Solar and wind are already pushing coal and nuclear into unprofitable territory; you don't have to push them out entirely before fossil generators are no longer economical to run. You only need to push hard enough to create a downward spiral which causes utility scale battery storage to be cheaper (by soaking up power when prices are at zero or negative, and then discharging when there's demand). Large fossil generators can't run only half the day and still make money.

https://www.bloomberg.com/news/articles/2017-11-02/renewable...

https://cleantechnica.com/2016/12/25/cost-of-solar-power-vs-...


Natural gas killed coal and nuclear because natural gas plants have a) much lower capital costs. b) Can sell into the intermediate load market. c) natural gas is cheaper per MBTU than coal.

If you wonder why the Koch brother hate solar it's because Solar directly competes with natural gas in the intermediate load market. Which is where all the profit is.


Natural gas does have lower capital costs, but its clear the demand isn't there. Witness GE laying off large swaths of its gas turbine division [1] (and as Bloomberg puts it, "Gas-turbine maker hurt by slowdown as renewables gain ground").

Natural gas is cheaper than coal currently [2]. Depending on demand and fracking, it may not stay cheap. That spot market price spike is when batteries will make in roads.

[1] https://www.bloomberg.com/news/articles/2017-12-07/ge-is-sai...

[2] https://ycharts.com/indicators/natural_gas_spot_price


> but its clear the demand isn't there.

That's because the cost of solar and wind are dropping fast creating the following cost hierarchy

Wind -> Solar -> Nat Gas -> Coal -> Nuclear


I downed this comment because u wrote: “Koch bros hate solar”

Ur repeating something, I guess... but it’s totally not sourced. I read a rolling stone article before posting this message that suggested they fund ALEC, but that same article seems to hate on "profit" in a way i have difficulty relating to. I’d bet even SolarCity funded ALEC.


> ALEC

You brought that up not me.

My source is a lawyer that used to work on utility regulation for a state I'm not naming.


With uncontrollable sources like solar and wind, aren't peakers even more necessary?


Hydro with a reservoir is a good peaker, which often happens to be more plentiful in roughly the same areas where solar and wind are also abundant.


>...I would be shocked if there's any fossil fuel generation online in 10 years, 15 tops.

The odds of that actually happening are zero.

For example, the National National Renewable Energy Laboratory, tried to model what it would take for California to get 1/2 its power through solar.

>...Those can only go so far, though. To meet the 50 percent photovoltaic threshold economically will require energy storage. The state already has 3,100 megawatts of pumped storage, with 1,325 megawatts of additional storage set to be deployed by 2020, per the state mandate. Under the most optimistic flexible grid scenario and with PV prices falling rapidly to 3 cents per kilowatt-hour, California will need another 15 gigawatts of storage by 2030.

>That’s more than 11 times the amount mandated currently in California, and 66 times the total megawatts deployed in the U.S. last year. And any delays in the price declines of solar, or the rollout of EVs, or the flexibility of conventional power plants, will raise the bar on the amount of storage required.

>That sounds daunting, admitted NREL Principal Energy Analyst Paul Denholm, who co-authored the research with Robert Margolis.

>“Storage costs are going to have to come down,” Denholm said. “I don't want to sugar-coat it: we're not there yet.”

https://www.greentechmedia.com/articles/read/how-much-energy...

As Bill Gates said in an interview about this kind of advocacy: "…They have this statement that the cost of solar photovoltaic is the same as hydrocarbon’s. And that’s one of those misleadingly meaningless statements. What they mean is that at noon in Arizona, the cost of that kilowatt-hour is the same as a hydrocarbon kilowatt-hour. But it doesn’t come at night, it doesn’t come after the sun hasn’t shone, so the fact that in that one moment you reach parity, so what? The reading public, when they see things like that, they underestimate how hard this thing is. So false solutions like divestment or “Oh, it’s easy to do” hurt our ability to fix the problems. Distinguishing a real solution from a false solution is actually very complicated." https://www.theatlantic.com/magazine/archive/2015/11/we-need...

Gates is investing in 4th gen nuclear and energy storage companies so he is putting his money where his mouth is.

China is investing a lot of money in solar, but they don't pretend that will solve all the problems of producing power. China plans to have 1400 GW of nuclear power by 2100, so they also realize that the situation will require a multi-faceted approach.

https://en.wikipedia.org/wiki/Nuclear_power_in_China


That's assuming that all panels are outputting their max all day every day. Obviously not the case, since night and clouds exist.


Those seem like they are out west, so besides night, they should get fairly good utilization (western China is very much like inner western USA).


Is there a better way to communicate this news?


It really depends on the publication's target audiance. For the less technical reader an estimated power output converted to "households" is a good unit of measurement. I think maximum capacity in Gigawatts works well for CleanTechnica.


China has rightly realized that poisoning the population and polluting the world will not make its wealthy people any wealthier, nor will it help the country grow economically.

The USA, on the other hand, still firmly believes that coal, oil, and other poisonous, polluting substances that harm citizens and life across the whole world, is worth it because the owners can still make money doing it. Rather than tell them it is illegal and to stop harming us, we give them subsidies and tell them to speed up (drill baby, drill! [1] coal jobs! [2] removing subsidies for renewables [3]! bomb them and take their oil! [4] etc).

This won't make the rich any richer, not in the long term. It will destroy the livelihoods and bank accounts of the people who would have otherwise spent all their money on products and services that help the rich get richer.

If America really cared about capitalism, it would work quickly to shut down the polluting industries by force and replace them with reusable energy. By definition, American capitalism has a near-term local maximum, defined by its choice to intentionally not be a sustainable, growing, economically viable civilization.

[1] https://en.wikipedia.org/wiki/Drill,_baby,_drill

[2] http://www.politifact.com/truth-o-meter/promises/trumpometer...

[3] http://www.newsweek.com/trump-set-slash-energy-subsidies-han...

[4] https://www.thedailybeast.com/trumps-take-the-oil-madness


I live in a state that gets most of its electricity from hydro. I’m enjoying air that is much cleaner than when I lived in Beijing (we left because of the pollution).

You are comparing third world problems to first world ones, China has a massive problem today, the USA has mostly solved those. E.g. PM2.5 rarely goes above 100 in most USA cities, that AQI was considered normal in China until very recently, which definitely wasn’t sustainable. It’s great that China is solving its pollution problem; but this doesn’t have much to do with the USA unless you want to talk about carbon instead.


Air quality is merely one measure of how this stuff hurts a population. There is massive poverty in the USA. And these huge oil companies who start fracking? They literally destroy people's homes and don't care.

http://insideenergy.org/2016/03/30/oklahoma-earthquakes-who-...

> but this doesn’t have much to do with the USA unless you

The parent comment was all about the USA. I am responding to a comment directly about the USA and its ability/desire to implement renewable energy.

> You are comparing third world pro or s to first world ones

I am not. Much of the US is living in third world conditions [1], despite the definition meaning originally ~"not the US or Russia", an enormous amount of people in the US live in poverty, and a lot of them next to huge corporate pollution nightmares. West Oakland is a good example. These people have lifelong respiratory problems and few people care - certainly not the city nor the company who gave those people long term health problems. That pollution mostly comes from the Port - but my point still stands.

If you think the US is "mostly solved" when it comes to pollution you are dearly wrong.

> A unless you want to talk about carbon instead.

That's pretty much all I was talking about in the first place.

Edit: [1] I'm being told off for this comment, like it isn't true or something? But a commenter below told me that something like 40M people in the USA live in poverty. That's a big number, and certainly is "much of the US". I'm not wrong about a very, very large number of people in the US living in poverty.


> Much of the US is living in third world conditions,

I'm guessing you've never been to Haiti, Kenya, Rwanda, or any actual third world nation, have you?

> an enormous amount of people in the US live in poverty

The poverty rate in the US is similar to that in France, the UK, and Canada - about 1/3-1/5th that of actual third world nations.


PM 2.5 is an immediate non-abstract threat that really sucks if you have to live it. If you think the respiratory problems are bad in Oakland, that is nothing compared to what is happening in much of eastern China. Again, the scales are completely different and incomparable.

If you want to start talking about carbon, I don’t think a higher or lower carbon footprint would have forced me to leave Beijing for the states. Ya, it eventually kills the planet, but it doesn’t effect immediate quality of life.


I am aware the problems in China are large, and different. I didn't mean to suggest otherwise. The USA also has an immediate existential crisis right now when it comes to pollution. To deny that is exactly how we got into such a disaster in the first place.

> Ya, it eventually kills the planet, but it doesn’t effect immediate quality of life.

I disagree with everything I am. It does immediately affect quality of life. For one, changing climate in the Bay Area and in Colorado locally is a result of changing global climates. These affect people, crops, plants, animals, everything, immediately.

Personally, my quality of life has been dramatically reduced for 30 years due to global warming and climate change from local carbon outputs. To suggest otherwise is extremely close minded and offensive.

Growing up in world and being told it is totally wrecked for generations, told that the greed of our parents' generation and before that has ravaged the Earth so completely that problems are spiralling out of control and life will be increasingly hard and complicated for people all over the world for a long time. Being told that hundreds of millions of people will be low on food due to changing climate patterns, that this is already happening, that there are droughts and wars fought over this already.

> but it doesn’t effect immediate quality of life.

Yes it does. People have died. Please be more considerate and understanding of the immense damage caused by greed and greenhouse gas pollution that is presently happening.


Let’s put it this way: I don’t think you have ever experienced an 800 PM2.5 day before. You would move if you did, I assume you are still living in the Bay Area, however bad you think the pollution is there, it didn’t cause you to pick up your life and start over again. In that case, your values aren’t incredibly different from mine.

Let me know if any of my assumptions are incorrect.


No, I have not experienced a day like that. I'm sure I would move, too. I wasn't suggesting otherwise.

Downplaying the USA's problems with pollution and dangerous materials has been a major problem for hundreds of years. The attitude that "it's worse elsewhere, America has it solved" is so incredibly dangerous. It's just not true. America does not have any of this solved. America is trying its best right now to increase the pollution in cities and decrease the air quality.

Maybe the air quality isn't that bad right now, according to you or elsewhere. That doesn't mean it is okay to make it worse. That doesn't mean that we have solved it. Left alone to the current path of things, I think the USA certainly would bypass China in terms of bad air quality. The major leadership definitely wants that future it seems - that is the only end result of the current US policy.


>> There is massive poverty in the USA

This is simply false for any reasonable definition of "massive," especially anything relative.


No, it is not false. You may not be aware of it, but massive poverty in the US is certainly there. Massive? Yes of course there is. There are so many people in the US living at or near the legal definition of the poverty line - it's clearly a major problem. A massive problem for sure. The number of homeless people in California alone is an international tragedy.

The USA absolutely does have a massive poverty problem, and to deny this is to deny the reality and the humanity of your fellow citizens.

Edit: I think it would be reasonable to suggest that if there were more than a million people living in the USA in poverty, that we could all agree that it would fall under a reasonable definition of "massive poverty", relative or otherwise. And I don't know the numbers, but I guarantee that there are well over a million people living in poverty in the USA.

--------

Edit: I am banned from responding to comments on HN (too many downvotes? I'm not sure why. I've tried to be very polite here). Here is my reply to the comment below.

> So you keep using hyperbolic statements - massive, massive, massive, massive -

I am not the one who brought 'massive' to this conversation. I am using that word to respond as directly and clearly as possible to the commenters above.

> and then you admit you have no idea what you're talking about, because you don't actually know any numbers involved.

I did no such thing. I even took an educated guess at the numbers, which turned out to be conservative based on the numbers you supplied, and the number of poor people in the USA is 10x higher than I has estimated. Wow.

> That's pretty ridiculous to put it mildly.

I don't understand this at all. I'm not being ridiculous. That is rude. What do you mean by this?

> The US poverty rate in 2016 was 12.7%.

I would say that is very clearly massive poverty. It is completely unacceptable that a country as advanced and capable as the USA still has so much poverty. That's 40M people in poverty in the USA. Wow - that is a lot.

Please be kinder, both to me and to them.

Edit again:

> The term "massive" is a strictly relative concept.

No, it is not. I googled 'define:massive' just to check and was met with a set of reasonable definitions, all of which show that you are wrong. All of them.

I like definition 2. "exceptionally large." 40M people, living in the USA in poverty, is exceptionally large. That is not up for debate. That number is huge. It is exceptional and it is large - an exception to what the USA is capable of doing, an exception to what people expect when they pay so much tax, an exception to what the media, government, and our society expect.

Denying or diminishing the scope of the problems of poverty in the USA is harmful and insulting.


> And I don't know the numbers

So you keep using hyperbolic statements - massive, massive, massive, massive - and then you admit you have no idea what you're talking about, because you don't actually know any numbers involved.

That's pretty ridiculous to put it mildly.

The US poverty rate is comparable to the poverty rate in Canada, which is regarded as one of the most developed nations on earth and is believed to have among the highest standards of living. And when you adjust the poverty line income scales to match within a given society (ie what position the poverty income line represents), it's comparable to Germany and France as well.

The US poverty rate in 2016 was 12.7%.

For 2016, 4.8 million Canadians were estimated to live below the poverty line. That's about a 13.3% poverty rate give or take.

The term "massive" is a strictly relative concept. Its typical meaning is something being exceptionally large in comparison to something else. The US does not have massive poverty compared to eg the developed world median. Compared to the world median, the US has a low rate of poverty. Your premise is factually demonstrably false. If such highly developed nations as Canada, Germany and France are said to have massive poverty, the term "massive" in relation to that use loses all value. Exceptionally large poverty would be Haiti, which has a ~58% poverty rate, or over four times that of Canada - that's massive.


I guess you're not aware that the latest EPA rule proposals are taking aim at the very notion that PM2.5 is harmful (albeit indirectly)?

The legal authority to regulate PM2.5 is based on Harvard studies (that have been replicated) and private medical data from the 70s and 80s. The new EPA rule would forbid it from using non-public data (such as these medical records). The new rule would forbid using non-public datasets (such as medical records), which would make it practically impossible to issue regulations based on human health.


And it's a "proposed" rule, and that distinction matters.

Everyone sane agrees that the US is moving backwards on this issue right now. And likewise everyone can see that the numbers in the headline represent a huge step forward for China.

Nonetheless when comparing actual air quality[1] as measured by things like PM2.5, the US is remarkably clean and well-regulated even by standards of western democracies while China is starting from a state of pollution that the US never remotely approached.

Bucketing the world into Good Guys and Bad Guys works poorly if you want to effect real change.

[1] Per capita carbon output doesn't look nearly so good for the US, of course.


Interestingly, today's NASA Earth Observatory image of the day is "Smog Smothers Solar Energy in China" https://earthobservatory.nasa.gov/IOTD/view.php?id=92054

A quote from the article: "The researchers found that in the most polluted areas, available solar energy decreased as much as 35 percent, or 1.5 kilowatt-hours per square meter per day. That is enough energy to power a vacuum cleaner for one hour, wash twelve pounds of laundry, or run a laptop for five to 10 hours."


In some sense, it's enviable to be in a position where bringing more solar power online will increase the production of your existing solar! (by eventually reducing coal emissions and thus pollution)


Good point. Betting against your own failures is worth doing when you're fixing them.


Eastern China is not that great for solar anyways even without the smog: it would at least be foggy and cloudy even if the air was clean. Looking at the picture and reading the article, that capacity is mostly being installed out in western China where pollution (and densities) are much less of a problem. On the other hand, without super grid support, it isn’t going to help much in solving the east’s problems.


Love the salty comments on HN everytime China does something great.

"Well actualllllly"


Someone wrote this in the comment section of the article: "One of the most inspiring factoids for me is that a mere 10 years ago, 10 GW was the total accumulated installed capacity for the entire planet. And here we are with 1 single country installing that in 3 months."

If true, this is amazing !


I was trying to get context on this number- 10 Gigawatts of power is enough to power 7,000,000 western homes!

China is supposed to have 455 million homes, and there is no way the average chinese household uses as much electricity as a western one, but I don't know how to make a reasonable comparison.

Also in the US, commercial and residential use accounts for 40% of energy use, so this should be a pretty substantial amount of clean energy, even for a country as big as china.


Was curious too so did some Napkin math with some numbers I found.

10GW Solar Nameplate capacity added in Q1Y2018

17% Capacity factor (Average for solar in China) [1]

1135 kWh (1.12 Mwh) avg annual household electricity use [2]

Makes it: 10GW nameplate capacity * hours in Year (24 h * 365 days) = 87600 GwH (theoretical maximum generation)

Expected actual generation = Capacity factor (17%) * Theoretical maximum generation 87600 GwH

= 14600 GwH annually

14600 GwH( 14,600,000 MwH ) expected generation in a year / 1.12 MwH consumed per average Chinese household means

= ~ 13 Million Chinese households powered per year due to the solar installed in these 3 months

[1] capacity factor from Wikipedia (1st paragraph) https://en.m.wikipedia.org/wiki/Solar_power_in_China

[2] average household electricity usage by country 2010 data http://shrinkthatfootprint.com/average-household-electricity...


That 10 Gigawatt number is the 'nameplate' number, not it's actual production capacity. The nameplate number assumes the panels are in 100% perfect sunlight 24/7 - typical production numbrees range from 10-20% depending on location, weather, air pollution, and time of year.


It is also enough to power 8 DeLoreans!


This should be the new official measuring units for all green, fusion and time-travel related articles


The UK's largest power station Drax had a 4GW capacity at its peak, and the current UK demand is in the region of 40GW.


My rule of thumb: solar power generates 10 watts per square meter.

There's a fixed maximum of 1300 watts per square meter of sunlight. For large scale technology, assume 10% efficiency. Another 10% from that survives air occlusion, clouds, night, angles, dust/snow cover, buffer battery efficiency, maintenance, breakage, etc. Round down, and we see 10W/m^2 practical output.

Professional quantification of this back-of-the-napkin calculation welcome.


Your rule of thumb is fine. That's roughly how much large-scale solar farms built a few years ago are producing over the course of a year in the California desert. As module efficiency goes up the number will trend up a bit over time in desert locations, but as costs fall more farms will be installed in less-sunny locations as well.

Unlike my sibling poster, I don't expect solar thermal to do significantly better on areal efficiency. The captured-sun-to-electricity efficiency can be higher, but the mirrors need to be spread out more than PV modules need to be separated. Ivanpah covers 14.2 km^2 and generated 719398 MWh in 2017.

https://en.wikipedia.org/wiki/Ivanpah_Solar_Power_Facility

Annualized, that's

(719398 / (24 * 365)) / (14.2 * 1000 * 1000) * 1000000 = 5.8 watts/m^2. Solar PV farms in a similar climate are doing significantly better.

https://en.wikipedia.org/wiki/Desert_Sunlight_Solar_Farm

Desert Sunlight's annualized generation was, using the wiki data again,

(1346282 / (24 * 365)) / (16.0 * 1000 * 1000) * 1000000 = 9.6 watts/m^2.

I know that Ivanpah has been troubled. I'd welcome annualized areal power figures from a better-performing solar thermal generating project if anyone has them.


> My rule of thumb: solar power generates 10 watts per square meter.

> There's a fixed maximum of 1300 watts per square meter of sunlight.

I'd suggest you qualify your numbers by noting that you're talking specifically about Solar PV.

Solar Thermal appears to offer 3x the kWh/m2 over Solar PV -- and mitigates at least one of your concerns ('night'). That ratio will doubtless change as PVC efficiency improves, but if that 3x factor is accurate now, it'll be a long time before PVCs match or exceed on square metre ratings alone.


Solar Thermal appears to offer 3x the kWh/m2 over Solar PV

I'm wondering at the difference between your measuring "kWh/m2" vs mine of "W/m2". Upshot: averaged over a year, what's the power output? are you including all "off" hours?


Good question. I simply did some googling for comparative efficiency per unit area between PVC and solar thermal -- the 3x factor seemed to come up regularly from different sources. The kWh/m2 was the unit most of those sources were using.

Time of day is very interesting, as PVC's are going to be useful earlier in the day, and solar thermal can still be providing good power output well after sunset. Consequently, in practice, I'd see a combination of both technologies (combined with good storage and grid capabilities, etc) as being most effective way of harnessing sunlight in the short to medium term.

Averaging over a year ... geo / climate variations (eg distance from equator, monsoon cycles, etc) are likely going to affect both technologies similarly.


Is this going to be a massive maintenance problem in ten years time? I thought that’s the lifespan of panels.

Usually the problem with building lots of infrastructure is it gets expensive to maintain. It happens with roads and buildings. Will it happen with solar?

(I’m hoping not because efficiency is still improving and prices are still going down whereas for roads I think it went up - but I don’t know why).


Actual usable lifetime is significantly longer. There's a good compendium of information here:

https://www.nrel.gov/pv/lifetime.html

If you want to do a deep dive, the open preprint of "Photovoltaic Degradation Rates: an Analytical Review" is a good start:

https://www.nrel.gov/docs/fy12osti/51664.pdf

It's from 2011 so is a little dated, but later studies have found about the same degradation rates. It's good because it uses data from large numbers of real-world solar installations. Most degradation studies are reporting on only a small number of modules and/or use artificial accelerated aging conditions.

The median degradation rate for crystalline silicon PV modules was found to be 0.5% per year. This would imply more than 40 years for the median module performance to decline to 80% of original rated output. I personally use 30 years as a more conservative rule of thumb, especially since modules appear to follow a degradation "bathtub curve." But it is clear from field data that the median solar module produces useful power levels far longer than 10 years. I suspect that modules designed for durability can achieve median lifetimes over 50 years.


80% of power at 20 years is fairly standard for solar panels. It's a slow taper too, you just lose around 1% of output each year you sweat them.

There'll be other losses due to failures, damage etc. but it's not a situation where you should factor in a strict capital replacement cycle.


You should always factor in a capital cost (replacement, repair, etc).


Doing it in the accounting manner that a typical firm would do is foolish in this instance.

A homeowner is going to sweat assets, and in the case of Solar a 1% degradation per year means that, short of some damage or failure, the time you're likely to sweat them is between 20 and 80 years.


25-30 years. 80% efficiency after 20 years.


Will China be the first regime to have carbon neutral high-tech mass surveillance?

With their newfound riches, imagine what futuristic, renewables-powered dystopia will flourish there.


As opposed to the USA's coal driven mass-surveillance? All developed countries are performing mass surveilance of their citizens, some are more visible (and restrictive) than others.


Disapprove of their government by all means, and even apply diplomatic pressure to encourage them to change it, but I can hardly see why anyone would want to mock their development of renewable energy. If they don't, the whole world suffers.


I don't know if he's mocking China. He is is expressing the ambivalent feeling that many have about China, and he's doing so in a bit of a comedic way.


I am all for witty sarcasm, but this one doesn't add much value to the discussion given weak correlation between mass surveillance and renewable energy.


Is there a weak connection when one literally powers the other?


You are making assumptions. How do you know what powers or will power the surveillance system in China? Also, mass surveillance will always be there regardless of forms of energy it is on, hence the weak correlation.


Not to mention running these video cameras and computer systems is fairly minor in terms of how much energy they consume compared to other activities in the country.


Do the ends justify the means?


This is a bit far-fetched. Not everything China does is for mass surveillance...this could simply be the Chinese government had a taste of how bad Beijing's air quality is and decided to push harder towards renewable energy.


> futuristic, renewables-powered dystopia

Why is it a dystopia?

Assuming one day China goes to space, achieved nuclear fusion. Would human being be more freed in that way than stuck in the freedom in a tiny ball of mud in the universe?


Free to go to space, but not free to criticize your government. Nope, that's not real freedom.


I was implying that earth government are not going to control outerspace nations.


Oh, I see.


This is incredible. If only they also stopped investments in fossil fuels... Chinese banks are by far the largest investors in fossil fuel projects today.


http://environmentalresearchweb.org/cws/article/news/71465

I couldn't find it for solar but it should be similar if I remember correctly. China has created almost TWICE the number of GW of capacity for wind than the United States but USA still gets almost the same renewable energy from wind as china because US is 93% more efficient at generating wind due to a whole lot of reasons, but primarily because of capitalism and market economy driving decisions rather than the State.




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