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Solar Is Top Source of New Capacity On the US Grid In 2016 (arstechnica.com) 192

An anonymous reader quotes a report from Ars Technica: The U.S. electric grid continued to transform in 2016. No new coal plants were added, and solar became the top new source of generating capacity. Combined with wind, a small bit of hydro, and the first nuclear plant added to the grid in decades, sources that generate power without carbon emissions accounted for two-thirds of the new capacity added in 2016. These numbers come from the U.S. Energy Information Administration, which asked utilities about what sources they expected to have online at the end of the year. These numbers typically show a burst of activity in December, as projects are raced to completion to take advantage of the tax benefits of reaching operational status in the current year. Overall, the EIA recorded 26 GW of new capacity added to the grid in 2016. This includes a small amount (0.3GW) of new hydropower and a smattering of projects collected under "other" that produce a similar magnitude. Notably absent from the list is coal. Also absent is distributed solar, meaning panels installed on homes and other small-scale projects. Distributed solar accounted for about 2GW of new capacity in 2015, and the EIA notes that the incentives for these projects haven't changed considerably in 2016. Even without that 2GW, solar comes out on top, with 9.5GW of new additions this year. At 8GW, natural gas comes in second place on the EIA's list, followed by wind at 6.8GW. Thanks to the opening of a new reactor at Watts Bar in Tennessee, nuclear also joins the list for the first time in years, adding 1.1GW of capacity. Combined, wind, nuclear, hydro, and solar account for 68 percent of the new additions, making 2016 a low-carbon year for the U.S. grid. Assuming distributed solar this year is similar to its 2015 levels, the percentage of new non-fossil generation goes up above 70.
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Solar Is Top Source of New Capacity On the US Grid In 2016

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  • Total Capacity (Score:3, Interesting)

    by cirby ( 2599 ) on Monday December 19, 2016 @09:16PM (#53519075)

    Not total delivered.

    So when you see that 9.5 gigawatts of solar compared to 8 gigawatts of natural gas, it's more like 3 gigawatts of average solar output versus 7 gigawatts of gas...

    • Re:Total Capacity (Score:4, Insightful)

      by tomhath ( 637240 ) on Monday December 19, 2016 @09:25PM (#53519137)
      Watts Bar 2 nuclear plant will probably produce more power than that solar "capacity".
      • Re:Total Capacity (Score:5, Informative)

        by WolfWithoutAClause ( 162946 ) on Monday December 19, 2016 @11:06PM (#53519679) Homepage

        No, actually pretty similar on average; the solar may even edge it. The nuclear reactor obviously has higher power at night, but much lower power during the day than the solar. The average capacity factor of solar is about 10-20% depending on location, so 9GW of solar will produce somewhere between 0.9GW and 1.8GW on average, whereas this is a 1.2GW reactor; and the solar was installed much, much more quickly, and probably cost roughly the same or even less than the nuclear.

    • Re:Total Capacity (Score:4, Informative)

      by Solandri ( 704621 ) on Monday December 19, 2016 @09:53PM (#53519283)
      They're playing some tricks with the numbers [euanmearns.com] to get capacity factors close to 0.3, which is physically impossible unless all your PV panels are super-high efficiency and track the sun. But this isn't the sort of thing you can just cover up. It's trivial to calculate the actual capacity factor for PV solar:
      • Installed peak capacity [wikipedia.org] at the end of 2014 and 2015 was 18,173 MW and 25,459 MW respectively. So figure average capacity for 2015 was (25459 + 18173)/2 = 21,816 MW.
      • PV solar generation for 2015 was 23,232 GWh.
      • There are 8766 hours in a year (factoring in leap years).
      • (23232 GWh) / (21.816 GW * 8766 hours) = 0.121 capacity factor.

      So that 9.5 GW of solar capacity is only generating about 1.15 GW of power on average. If you add the 2 GW of distributed solar (rooftop panels) it works out to 1.39 GW average generation.

      Natural gas is a bit of a wild card, since it (and hydro) is typically used to follow peaking demand. That is, you don't run them full tilt. They top off power generation to match demand. But its (and hydro's) capacity factor is historically around 0.40. So NG's 8 GW translates into 3.2 GW of average generation. Hydro's 0.3 GW translates into 0.12 GW of average generation.

      Wind's capacity factor is about 0.25. So its 6.8 GW capacity works out to 1.7 GW of average generation.

      Nuclear's capacity factor is about 0.9. So the lone new nuclear plant at 1.1 GW capacity translates into 1 GW of average generation.

      So in terms of actual power generation:

      • Gas = 3.2 GW
      • Wind = 1.7 GW
      • PV solar = 1.15 GW (or 1.39 GW)
      • Nuclear = 1.0 GW
      • Hydro = 0.12 GW
      • Re:Total Capacity (Score:4, Informative)

        by K. S. Kyosuke ( 729550 ) on Monday December 19, 2016 @10:53PM (#53519643)

        to get capacity factors close to 0.3, which is physically impossible unless all your PV panels are super-high efficiency

        How did you conclude that panel efficiency impacts capacity factors? That doesn't make sense. Efficiency as a multiplier scales both maximum and average generation from a unit of insolated surface. The ratio of these two therefore shouldn't change (modulo possible spectral sensitivity effects for direct insolation vs. overcast for the different technologies, but these aren't in any simple way connected to overall efficiency).

        • How did you conclude that panel efficiency impacts capacity factors?

          A more efficient PV cell is easier to activate under low light. It takes a certain level of light to get a PV cell to overcome it's internal resistance, if this resistance can be lowered then it can operate through a larger part of the day. If the PV cell can operate through a longer period in the day then the capacity factor increases.

          • A more efficient PV cell is easier to activate under low light.
            That is bollocks. The amount of photons able to kick an electron into the conducting band depends on the doting and the kind of 'junctions'. In the bandwidth of light spectrum where a solar panel is working it is already very efficient regarding that frequencies.
            It takes a certain level of light to get a PV cell to overcome it's internal resistance,
            No it does not. Resistance has nothing to do with light level. The question only is: are there en

            • No need to get your panties in a wad over this. I'm not a fan of solar power but I am pro-arithmetic. If solar panel efficiencies can be improved then it can improve capacity factors. I didn't claim it would be much, only that it is possible.

              There are losses in the conversion, transmission, etc. If efficiencies can be improved then the capacity factor can improve. Again I made no claim it would be much, only that it would be measurable.

              • by Rei ( 128717 )

                Except that's not how it works. The nameplate capacity of a solar plant is based around how much power it produces in ideal lighting conditions. If you use more efficient panels, then you've upped the nameplate capacity, not the capacity factor. The capacity factor is average actual generation over nameplate.

      • Re:Total Capacity (Score:4, Interesting)

        by pointybits ( 818856 ) on Monday December 19, 2016 @11:08PM (#53519693)

        They're playing some tricks with the numbers [euanmearns.com] to get capacity factors close to 0.3, which is physically impossible unless all your PV panels are super-high efficiency and track the sun. But this isn't the sort of thing you can just cover up. It's trivial to calculate the actual capacity factor for PV solar:

        • Installed peak capacity [wikipedia.org] at the end of 2014 and 2015 was 18,173 MW and 25,459 MW respectively. So figure average capacity for 2015 was (25459 + 18173)/2 = 21,816 MW.
        • PV solar generation for 2015 was 23,232 GWh.
        • There are 8766 hours in a year (factoring in leap years).
        • (23232 GWh) / (21.816 GW * 8766 hours) = 0.121 capacity factor.

        Yeah sure, there's a conspiracy to cover up the real numbers. Or, you know, you might have botched your calculations. You took the solar output from large utilities only and divided it by the total solar capacity including distributed generation.

        Solar capacity factors of >25% are relatively easy in the sun belt and can go as high as 36% with tracking and a high panel-to-inverter ratio (Lawrence Berkely study, 2014 figures [lbl.gov]).

        • Solar capacity factors of 25% are relatively easy in the sun belt and can go as high as 36% with tracking and a high panel-to-inverter ratio

          No, 25% is top end for the sunny southwest, certainly above average for fixed panels in that region. US average is a lot lower. And nobody is installing tracking PV, for the cost is too high and it requires too much maintenance, it works out better to just pay for more fixed panels.

          • by Rei ( 128717 )

            Boy, gee, your counter of a peer reviewed study with "flat assertion from Mr D from 63" sure is convincing!

            Figure 8 supports this hypothesis by breaking out the average cumulative net capacity factor by project vintage across the sample of projects built in 2010, 2011, or 2012 (and by noting the relevant average project parameters within each vintage). As shown, the average capacity factor does not differ much on average between 2010- and 2011-vintage projects, which makes sense given the lack of significan

            • Considering that those "select" projects from 4 years ago used to calculated that maximum included those employing tracking, my point stands.
              • by Rei ( 128717 )

                The paper defines the sample:

                At the close of 2013, at least 64 utility-scale PV projects totaling 1,532 MWAC had been operating for at least 1 full year (and for as many as 6 full years), thereby enabling the calculation of capacity factors.

                What about that do you object to? Do you want them to include plants that haven't been run for a full year? Furthermore, the study was clearly conducted in 2014 because that's when the newest reference is (even though the PDF date is 2015). So exactly where's the prob

                • I don't object to anything at all. But it was clear my point regarding CF was related to fixed panels, so if you want to include tracking the numbers are certainly higher. Furthermore, one could question why they would not include inverter drop as for any other source CF is calculated on what is delivered to the grid.
                  • by Rei ( 128717 )

                    Because inverters aren't always sized to the maximum physically possible for the panels to deliver; it's not always worth sizing it to the maximum physically possible generation.

                • Also, if you look at that paper, Fig 7 shows the only ones up around 30% are in irradiances of >7. If you looks at non-tracking in areas with irradiance less than 7, you'll see it maxes out at 25%. As you can see from an irradiance map, zones above 7 are pretty scarce.

                  http://www.nrel.gov/gis/images... [nrel.gov]
          • > And nobody is installing tracking PV, for the cost is too high and it requires too much maintenance,

            As of 2014, 61% of new utility-scale solar plants were tracking systems (https://emp.lbl.gov/sites/all/files/lbnl-1006037_slides.pdf) (see page 23). The 10% higher cost for the tracking hardware is more than offset by the extra output you get from always facing the Sun.

            • > And nobody is installing tracking PV, for the cost is too high and it requires too much maintenance,

              As of 2014, 61% of new utility-scale solar plants were tracking systems (https://emp.lbl.gov/sites/all/files/lbnl-1006037_slides.pdf) (see page 23). The 10% higher cost for the tracking hardware is more than offset by the extra output you get from always facing the Sun.

              To my knowledge, the use of tracking has significantly dropped in newer installation. I don't recall any recent projects that included it, but I don't have a list of all installations so maybe that is incorrect. If you include residential PV, tracking is even a smaller percent of the total. Why spend 10% more for 5% increase in CF when you can get 10% increase in total capacity for that same investment? Plus take on the added maintenance costs and reduced generation when a tilt motor fails. In some places t

      • First of all the capacity factor is not related to efficiency.
        If I produce 1GW with a 4GW panel because it is only 25% efficient has nothing to do with the capacity factor which is basically only the number of sun hours per year.
        Furthermore in your bullshit calculation it would make much more sense to use GWh produced, and not GW 'adjusted to capacity factor' because in full sunlight a 4 GW solar panel will surprisingly produce: 4GW, hence the nameplate.

        Bottom line: you should stop using metrics from which

        • by Rei ( 128717 )

          Indeed. Up to a certain point adding more solar actually makes load following easier. Also, wind and solar tend to run opposite each other: solar peaks in the day, while wind peaks at night; high pressure systems bring low wind and high sun, while low pressure systems bring high wind and low sun; etc.

          Solar and wind both benefit greatly however from a HVDC grid, to allow for timeshifting - aka, people using power after the sun's gone down from a place where the sun is still up, and vice versa. The last s

    • Actually at peak the solar plant will deliver its 9.5 peak. Same for the gas plant ... and the gas plant has no CF of 100% either, unless it is a base load plant then it likely runs at 95% power output with enough down time to have a CF of about 90%.
      In real life a gas plant will be at absolute minimum at night, barely producing power, and load following between roughly 9AM till 5PM or 7AM and 7PM at decision of the operators, so its CF is just about 45 percent, as most power plants that are not used for bas

    • Not total delivered.

      So when you see that 9.5 gigawatts of solar compared to 8 gigawatts of natural gas, it's more like 3 gigawatts of average solar output versus 7 gigawatts of gas...

      And? I would look at those numbers and do some quick calculations about an inplace technology that is now providing almost half of the power that a technology that involves drilling and pipelines, trains, compressor stations, and a lot of infrastructure.

      We are seeing some models already. A local small power generating plant, designed to supplement the power system as needed, generates power and steam heat from natgas. Uses essentially a Jet engine turbine, and collects the waste heat for heating buildi

  • by kenh ( 9056 ) on Monday December 19, 2016 @09:21PM (#53519105) Homepage Journal

    No new coal plants were added, and solar became the top new source of generating capacity.

    Want to guess why? Because one is subsidized and the other was successfully taxed and regulated out of existence.

    • by ShanghaiBill ( 739463 ) on Monday December 19, 2016 @09:38PM (#53519207)

      Because one is subsidized and the other was successfully taxed and regulated out of existence.

      Exactly. It is totally unfair that coal plants had to stop spewing soot and sulfuric acid into the atmosphere. We need to make America great again!

    • by santiago ( 42242 ) on Monday December 19, 2016 @09:41PM (#53519233)

      No new coal plants were added, and solar became the top new source of generating capacity.

      Want to guess why? Because one is subsidized and the other was successfully taxed and regulated out of existence.

      No, it's for the same reason there was no capacity added from burning whale oil, namely that it's not economical. Natural gas (#2 on that list) is what kicked coal to the curb, not environmental regulation. There's lots of articles covering this, such as this one from not-exactly-a-bastion-of-liberal-thought Reason magazine [reason.com].

      • by Darinbob ( 1142669 ) on Tuesday December 20, 2016 @02:07AM (#53520267)

        If I was one of the leaders in the coal industry, I most certainly would tell the angry workers with pitchforks that it was the government's fault that they were laid off. I certainly wouldn't want to tell them the truth that it was because they weren't making me enough money.

    • Not counting cutting wood on your farm, name one energy source that wasn't subsidized as it replaced the prevailing source. Camphor oil, whale oil, kerosene, oil, coal, nuclear, hydro have all been the beneficiary of federal subsidies, some much more than others.

      If you own coal futures and want to see them do well you'd be much better off blowing up some natural gas refineries than worrying about solar.

      • I don't know this for a fact but I recall reading something on how farmers would make their own alcohol to run their tractors until Prohibition. There were no ethanol subsidies then but the farmers were quite willing to replace gasoline and kerosene for moonshine.

        I believe that Prohibition set back the bio-fuel industry by more than a century. We'd have had all kinds of real world data on the utility of ethanol as a fuel if Prohibition didn't kill it off. Even after Prohibition ended there were still "re

        • by boskone ( 234014 )

          the old tractors would run on old motor oil too (that you could get for free at the corner garage or from your other equipment).

          you could start them on a cup of gas, switch to running on oil, run on old oil all day and then that night use another cup of gas to clean up the plugs and carb. So two cups a day of "paid for" fuel.

          moonshine is a little more valuable than gas so even with zero regulations, I think folks would just buy gas and drink/sell the shine

    • by whoever57 ( 658626 ) on Monday December 19, 2016 @10:02PM (#53519323) Journal

      Want to guess why? Because one is subsidized and the other was successfully taxed and regulated out of existence.

      This is complete bullshit. The reason is simpler: natural gas because cheaper. Coal was out-competed by fracking.

      The free market killed coal, not regulations.

      The only way coal will continue is if it is subsidized more than it is already (by not having to clean up the mess created by coal).

      • This.

        We have so much goddam natural gas we export it.

        U.S. Liquefied Natural Gas Exports [forbes.com] Reach A New Market And Continue To Climb In 2016. In the first six months of this year, nearly 50 Bcf of U.S. LNG was exported. We will be surging to a dominant role in less than five years, with five terminals operating on the Gulf Coast and in Maryland by 2020.

  • Solar for your home (Score:5, Interesting)

    by FrankHaynes ( 467244 ) on Monday December 19, 2016 @09:47PM (#53519253)

    Florida voters narrowly (and surprisingly, to me) defeated a constitutional amendment that was funded by Florida Power & Light and other very interested parties that would have made it difficult and expensive to install solar power in the home. A rare victory for common sense in Florida.

    http://www.miamiherald.com/new... [miamiherald.com]

    Google tells me that a ballot initiative by the Good Guys failed to achieve enough signatures to make the 2016 ballot (due to some scam artistry by the polling company they hired) so they will try for the 2018 ballot.

    https://ballotpedia.org/Florid... [ballotpedia.org]

    I'm not comfortable with amending the Constitution for something as specific as this, but I suppose they figure the legislature could be bought out by the incumbent power companies if it were a mere lowly law on the books.

    • There's a depressing irony in a battle over whether people should be allowed solar panels on their homes in the "sunshine state"
    • by antdude ( 79039 )

      http://channel.nationalgeograp... [nationalgeographic.com] talked about solar power in NV, FL, and India. It was an interesting episode. IIRC, it talked about FL's voters and how old power companies tried to block the solar companies. :(

    • Florida voters narrowly (and surprisingly, to me) defeated a constitutional amendment that was funded by Florida Power & Light and other very interested parties that would have made it difficult and expensive to install solar power in the home. A rare victory for common sense in Florida.

      We massively went after the misleading amendment as well as promoting amendment 2 for medical marijuana. And if it weren't for the large number of old guard snow birds who keep settling in Northern Florida, the state would have turned blue. But that's another story.

      This time we wised up with the solar panel amendment.

    • > I'm not comfortable with amending the Constitution for something as specific as this,

      Southern states commonly put a lot of stuff in their state constitution, and require it be passed in a general election. The theory is it restricts the legislature from doing stuff the people explicitly have said they want or don't want.

  • The U.S finally managed to open it's first offshore wind farm. A whole of 5 turbines producing a paltry 30Mw of power, by comparison Europe added some 419 turbines producing over 3000Mw last year alone.
    • I we would halt all off shore wind farms and put them where the wind in strong and constant. Montana and the Dakotas. Place them among the farms, generate power all year long, day and night.
      • I we would halt all off shore wind farms and put them where the wind in strong and constant. Montana and the Dakotas. Place them among the farms, generate power all year long, day and night.

        There is a reason why the U.S built its Nuclear reactors close to population centers instead of building them in the middle of the Great Basin Desert. It is the same reason why we can't cover Montana and the Dakotas with turbines to power the U.S. Transmitting energy long distances is both expensive and inefficient due to resistance loss. In much of the North East land is expensive and as a result those states lag behind in wind power generation. Well other then the Southern States which have practically no

        • > mostly due to Political ideology against Climate Change Science

          No, it's because we have a lot of trees in the south, which causes friction and lowers wind speeds. It's no coincidence that most wind farms are in the midwest/Texas areas where it's flat open prairie and crop land. Wind speeds are actually just as high at higher altitudes in the South. The same weather systems blowing through other states eventually come here. But it's not economic to build wind turbines that tall yet. The same logic

      • And the blades would cool the land, counteracting global warming.

      • by Jeremi ( 14640 )

        I we would halt all off shore wind farms and put them where the wind in strong and constant.

        The wind offshore is strong and constant. That's one of the main reasons you'd want to put a wind farm there.

    • Comparing the EU to the USA in terms of where they build their Wind is like asking why there's no awesome swimming beaches right off the Norwegian fjords. The geography of one area is of a huge benefit to off-shore wind (very shallow waters in wind generating regions), while the USA's geography is far more beneficial to onshore wind (most of the USA coast has a very steep cliff just off the coast, that makes it good for surfing but not so much for construction.

      The USA has 48800 wind turbines. With a capacit

  • Cue the trolls (Score:5, Informative)

    by iris-n ( 1276146 ) on Monday December 19, 2016 @10:34PM (#53519521)

    Argh, the comments section of Slashdot is getting completely unreadable when the subject is something that is even vaguely related to global warming. Hordes of trolls rush to tell us that the globe is not warming, that this is all just a vast conspiracy by all the scientists in the world to get more research money.

    Come on, can't we get something interesting? I remember that even last year there would be plenty of comments talking about insolation, capacity, load balancing, grid-level storage, price, subsidies, etcetera. Now it's just this nutjob shitfest.

  • in light of the Trump Administration. Solar is very cost effective when you account for all the externalities (e.g. pollution). But with enough deregulation that could easily change. Not that coal had been doing that will pre-Obama (a lot of it is used to make steel, and there's a glut of the stuff from China) but I could see a resurgence.

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